3.1 Coordination and response
Diagram 4.1 shows the transmission pathway of information from receptors in the ear to effectors U.
No Marking scheme Marks
(a) Name structures R and S in Diagram 4.1 2 R: sensory / afferent neurone
S: motor /efferent neurone
1 1 2 (b) State the function of R 1
P Sensory / R neuron conducts the impulse from the receptor to (its axonal end in) the central nervous system.
1 1
(c) Based on Diagram 4.1 describes briefly the pathway of transmission of information from the moment you hear the sound of the ringing telephone until you pick up the phone.
F1 receptor detects stimulus
P1 (is stimulated to) trigger nerve impulses in afferent neuron P2 (nerve impulses) are carried to the central nervous system
P3 (the central nervous system) integrates and interprets the information P4 then send new impulses
P5 are carried by motor/efferent neuron to effectors//effectors produces responds
1 1 1 1 1 1 2
3.2 The role of human Nervous system
No Marking scheme Marks
(a) Organisation of nervous system
Explain what would happen if structure P:afferent neurone is broken down 3 F-impulse cannot transmit form receptor to CNS /Brain &Spinal cord
E1-Brain cannot interpreted/integrates the impulse/information E2-Stimulus cannot detects
1 1 1 3 (b) The neurons
Diagram shows the pathway of transmission of information from receptor to the effectors Name the part labelled P,Q,R and S
P:afferent neurone Q:effector R:receptor S:efferent nuerone 1 1 1 1 4 (c) Based on diagram, Describe the transmission of information 3
F-Coordination starts with the stimulus and end with the response E1-Receptor detect stimulus and trigger nerve impulse
E2-afferent neurone transmit nerve impulse to central nervous brain
E3-Central nervous /brain &nervous interprete/integrate the impulse /information E4-Impuls transmit to effectors along efferent neurone to produce response
1 1 1 1 1 3 R S
No Marking scheme Marks (a) Essay enhancement corner
Diagram shows three types of neurons in human being .During types of neuron must be coordinated to react on stimulus
Ahmad is a Johor state goal keeper .Explain how Ahmad able to push the ball away from the goal post area in the penalty kick 10
P1-(moving ball is an external stimulus
P2-receptor in the eye pick up /detect the ball /stimulus P3-the receptor trigger/generate nerve impulses
P4-The nerve impulse transmit from the afferent neuron to interneuron in the brain
P5-The brain interprets the nerve impulse (from interleukins that the ball is moving to goal keeper/Ahamad)
P6-The brain decides what to do stimulus (to catch or push away the coming ball)//coordinate response
P7-Nervw impulse are transmitted from interneuron to efferent neuron across the synapse P8-Nerves impulse then transmit to muscle (effectors
P9-The muscle (in arm /leg) carry out the response P10-Ahmad able to push away the ball form goal post P11-impukse is transmitted across the synapse
P12-Between afferent neuron and interneuron//interneuron//interneuron and efferent neuron
1 1 1 1 1 1 1 1 1 1 1 1 10
No Marking scheme Marks (a) The Spinal cord and its function
The line X and Y cuts across part of central nervous system connecting to the sensory receptors of the fingers
In space provided, draw cross –section of a labeled diagram through X and Y of central nervous system 3
D: Able to draw traverse section though spinal cord1 L Able to label grey mater and white matter correctly 1+1
1 2 3 (b) The nuerones
Diagram 4.2 shows gap P between the axon terminal and dendrite terminal of two neurones.
State two differences between X and Z. X – Afferent neurone
P1 - Transmit impulses from the receptor to central nervous system P2- The cell body is located in the middle of the neurone
1 1 1 1
The transmission of information across synapse
No Marking scheme Marks
(a)
Name gap P
Synapse 1 2
(b) Name one example of chemical substances which is released across P
Neurotransmitter / acetylcholine/noradrenaline/dopamine/serotonin 1 1 (c) Diagram 4.2 shows the transmission of information across structure T.
Explain the role of P in transmission of nerve impulses. F -P is synaptic vesicle
E1 contains neurotransmitters
E2 which transmit the nerve impulses//convert an electrical signal to chemical signal E3 diffuse across W / synaptic cleft /synapse
E4 requires / using energy provided by mitochondria //active transport
1 1 1 1 1 2
(d) If the chemical substances release from P across W is reduced due to a neurodegerative disease, explain its effect to a person‟s health.
F due to lack of acytalcholine in the brain
E1 the person may suffer from Alzheimer‟s disease
E2 causes loss of reasoning/ability to care for oneself/intellectual ability/ memory/ speak/ write// confusion E3 can be inherited 1 1 1 1 2
No Marking scheme Marks (a) Diagram shows a structure of a synapse
Explain how the nerve impulse is transmitted across the synapse/ Explain the transmission of a nerve impulse from neurone P to neurone R across Q.8
P1 – Q is a synapse/ synaptic cleft.
P2 – The transmission of information across a synapse involves the conversion of electrical signal into chemical signal in the form of neurotransmitter.
P3 – Neurotransmitter is produced in vesicles in the axon terminal called synaptic knob. P4 – Synaptic knob contains abundant mitochondrion to generate energy for the nerve
transmission.
P5 – When an impulse arrived at the synaptic knob, the vesicles release the neurotransmitters into the synapse.
P6 – The neurotransmitters molecules diffuse across the synapse P7 – to the dendrite of another neurons.
P8 – Reaching R, impulse is converted back into electrical signal. P9 – The transmission of impulse in one way direction
P10 – since the vesicle containing neurotransmitter is only found in pre-synaptic membrane. 1 1 1 1 1 1 1 1 1 1 10 Nerve impulse Axon of neurone P Q Synaptic knob Dendrite of neurone R
No Marking scheme Marks (b)
Explain the effect of a pain killer drug on the transmission of nerve impulses.
P1- Nerve impulses reach axon terminal / synaptic knob P2- Energy from mitochondria
P3- Vesicles containing neurotransmitter
P4- Merged / fused with (pre-synaptic) membrane P5- Releases neurotransmitters
P6- Into synapse
P7- Drugs Neutralised / blocked / disintegrate the neurotransmitters P8- No / less neurotransmitters reach dendrite / next neurone P9- 1 1 1 1 1 1 1 1 1 8 Explain the transmission of impulse from one neurone to another neurone. 4
Pt..1 When an impulses arrives in the axon terminal
Pt. 2 it stimulates (synaptic) vesicles to move towards and bind with the presynaptic membrane Pt. 3 The vesicles fuse / release the neurotransmitter into the synapse
Pt. 4 The neurotransmitter molecules across the synapse to the dendrite of another neurone Pt. 5 Stimulated to trigger a new impulses which travels along the neurone
1 1 1 1 1 4
There are molecule that will not be reabsorbed, for example, drugs. Alcohol is an example of a strong depressant drug that interferes with coordination and judgment .Explain why alcohol abuse is dangerous to a driver
P1-block the release of neurotransmitters
P2-it will slow down the transmitter of impulses through synapse P3-slow down the coordination between nerve ,eyes and muscle
1 1 1 2
Voluntary action and involuntary action Disease of nervous system
Aspect Marking scheme Marks
Involuntar y action &reflex
arc
Name then part label P,Q and R in the spaces provided in diagram 3 P-Brain
Q-spinal cord
R: Peripheral nervous system/Spinal nerve
1 1 1 3 Labeling
Aspect Marking scheme Marks Arrange Based on the diagram ,complete the reflex arc for the impulse pathway in diagram 5.3
Note: 2-synapse 1-interneurone 2 1 3 Drawing Skill
Figure 5 shows the reflex arc that occurs when the finger is accidentally
Pricked with a needle. Complete the above figure by drawing the appropriate neurons involved in the reflex action. 2
3 Neurone -2m 2 nuerone-1m
2
1 3
A boy steps on a thorn when running in a field,he retracts his leg immediately. Draw and label
Criteria Marks
Functional diagram (d) -3neurones,receptor and effector Labelling
5-6 3-4
2 1
Arrow (direction of impulse) (a) 1
Total 4
Aspect Marking scheme Marks Drawing
Skill
Diagram 4.1 shows the cross section of the spinal cord and the reflex arc.
On diagram 4.1 draw the arrow on X, Y and Z to show the direction of the nerves
impulses on the reflex arc. 1 1
Importance State the importance of reflex action to us.
To protect the body against injuries 1 1
Difference Differentiate between the above reflex action with the voluntary action. 1 The reflex action is governed by the spinal chord whereas the voluntary action is governed by the cerebrum.
1 1
Explain the difference transmission of impulse in voluntary action and involuntary action 2
Voluntary action Involuntary action F-Impulse transmit form the brain to
skeletal muscle
Impulse transmit form the medulla ablongata to smooth muscle /cardiac muscle/gland
E-Example kicking ball Example heartbeat /peristalsis
1
1 2
Explanatio n
Explain how the arm will react in that situation. P1. The receptor receives nerve impluse P2. The nerve travels along the afferent P3. And is transferred to the efferent neurone
P4. At the axon terminal of the efferent neurone, the nerve impulse is transferred to muscle cell causing them to contract.
1 1 1 1
Aspect Marking scheme Marks Essay Diagram shows a reflex that involves neurone X and Y
Describe the reflex action 4
P1-the receptor at the terminal of x stimulated by the heat P2-the receptor generates a nerve impulse
P3-The nerve impulse travels along X /afferent neurone to the spinal cord P4-In the spinal cord, the nerve impulse is transmitted to an interneurone P5-From the interneuron, the nerve impulse is transmitted to an efferent neurone/neurone Y
P6-Nerve impulse travels along efferent neurone/Y and reach the effectors/muscle tussue/fingers
P7-Muscle contract to withdraw the hand/finger Any 4
1 1 1 1 1 1 1 4 Diagram show coordinating system in the human body Diagram 8.1 shows a reflex are
and diagram 8.2 shows the regulation of the blood glucose level
Describe the reflex action in Diagram 8.1 P1-Automatic response to a stimulus P2-Control by spinal cord
P3-Short pathway impulse does not enter the brain
P4-When the tip of finger touches sharp object pain receptor will be stimulated and produced nerve impulse
P5-The impulse travels in the sensory neurone into the grey matter of spinal cord P6-Impulse from interneuron travel into motor neurone to effectors
1 1 1 1 1 1
Aspect Marking scheme Marks Essay
(knee-jerk-reflex)
In an accident, a motorist was seriously injured and was sent to a nearby hospital. A doctor is going to do a knee jerk test to examine the patient‟s nerve system.
D-1 L-1 P1 -The knee jerk action involves two types of neurons named afferent and efferent
neurons.
P2 -As the hammer strike, the force stretches the quadriceps muscle and stimulates the stretch receptors in the muscles triggering a nerve impulses
P3- Afferent neurons transmit the information to the efferent neuron in the spinal cord P4 - The efferent neurons transmit the information to the quadriceps muscle as an
effector and the muscle contracts thus swing the leg forward
P5 - If the patient is able to swing the leg forward, it indicates that the patient‟s nerve system is still functioning
1 1 1 1 1 1 1
Aspect Marking scheme Marks Predict If efferent neurone is injured and damaged, predict what will happen to the person. 1
1. The nerve impulse will be sent from afferent neurone to the effectors 2. The effector / muscles will not contract
3. The hand will not be removed immediately from the needle. (Any one )
1 1 1 1
Explain the possible effects if the parts of X (afferent neurone) in the spinal cord is damaged.
Loss of some touch sensations 1 1
Disease of nervous
system
A disease related to the nervous system which usually affect the elderly people is caused by lack of the chemical substances in (c) ( ii)
Explain the disease . F – Alzhemeir`s disease P1- lack of acetylcholine P2- brain shrinkage
P3- show loss of intelligence/loss of memory/ mild confusion/poor concentration Any 2 OR
F2 – Parkinson disease
P4 – Lack of neurotransmitter / dopamine // hardening of cerebral arteries P5 – tremors / weakness of the muscle / muscle cannot function Any 2
1 1 1 1 1 1 1 2 Alzheimer‟s and Parkinson‟s diseases are related to nervous system. Explain the causes
and the effects of the diseases on victims
Alzheimer‟s Parkinson‟s
Caused by
- the shrinkage of brain tissues and lack of neurotransmitter. - usually affects the elderly
Caused by
- the reduced level of
neurotransmitter in the brain caused tremors and weakness of the muscles
- the hardening of the cerebral arteries Effect: - Loss of intelligent - Loss of memory - Poor concentration Effect:
- The muscle cannot function smoothly and become stiff and jerky in their action
2
2 4
Aspect Marking scheme Marks Disease of
nervous system
Compare Alzheimer‟s and Parkinson‟s disease
Alzheimer‟s Parkinson‟s
Similarities A neurological disease Usually affects the elderly
Differences Leading to deterioration/damage of the
nervous system functions
Causing tremors weakness of the muscles
Leading by deterioration /damage of the nervous system functions
Causing tremors/weakness of the muscles
Caused by the shrinkage of brain tissues/and lack of
neurotransmitters/acetylcholine
Caused by reduced level of neurotransmitter in the brain
Symptoms are loss of intelligence/loss of memory/mild confusion /poor concentration
Symptoms are the muscle cannot functions smoothly/muscle become stiff and jerky in their actions
Can be inherited Not inherited
1 1 1 1 1 1 1 8
3.3 The role of hormones in human The need of endocrine system
No Marking scheme Marks
Difference (Nervous& Endocrine )
Compare and contrast this two coordinating systems
Endocrine system Nervous system
Message transported in the form of impulse
Message transported in the form of electrochemical charges
Hormone travel in blood stream /without duct
Impulse travel in the neurone
Slow response Immediate response
Long term effects Short effects All endocrine gland are not directly
interrelated
Two neurone consecutive neurone are connected though synapse
2
2
2 2 2 10 Both Alzheimer’s and Parkinson’s disease afflict around 500,000 individuals
annually with their eroding and life-sapping effects
No Marking scheme Marks Difference
(Nervous& Endocrine )
Based on the statement, explain the difference between the endocrine system and the nervous system 10
Nervous system Aspect Endocrine system
External stimulus Stimulus Internal stimulus
Sensory organs Receptors Sensory cells
Electrical and chemical Impulse//nature of impulse Chemical// hormones Neuroine and synapse Medium of transport Blood
Rapid/fast Speed of transmission of impulse
Slow
Specific locations, organs Target organ Various organs
Quick and short Response Long lasting
1 1 1 1 1 1 1 4
No Marking scheme Marks
The role of coordination and response are carried out by two different system as shown in diagram, 7.2(a) and 7.2(b)
Describe both system based on the structure and function F1 Nervous system
P1 Consists of brain, spinal cord and neurons P2 Stimulates by external stimuli
P3 Send information in the form of electrical impulses P4 Impulse is transmitted via neurons to effectors F2 Endocrine system
P5 Consists of endocrine glands // glands without ducts P6 Stimulates by internal stimuli
P7 Send information in the form of chemical impulses/ hormones P8 Hormones is transported by blood to target organ
1 1 1 1 1 1 1 1 1 1 1 6 The endocrine system and the nervous system play importance roles in maintaining
homeostasis. Both systems often work together. For example ,certain part of nervous system stimulate or inhibit the release of hormone promote and inhibit the generation or nerve impulse .Hence despite having the nervous system the body needs the endocrine system
The human endocrine system
No Marking scheme Marks
(a) Diagram 4.1 shows the endocrine system in the body of a human.
Name the hormones secreted by gland P and Q P : Thyroxine
Q : ADH // FSH // LH
1 1 2 (b) Some people have their gland P grows two or three times its size.
(i) Name the condition mentioned above
Goiter 1 1
(c) (ii) Suggest how to overcome the above problem.
Taking enough iodine in our diet label adrenal gland with letter S correctly. 1 1
Based on the diagram, explain how hormone R is responsible for the difference of physical appearance if individual X and Y3
E1-Hormoane R stimulate growth
E2-Lack of hormone R cause stunted growth in Y E3-Over secretion of hormone cause gigantism
1 1 1 3
No Marking scheme Marks (a)
Name hormone P and R P:Thyroxin hormone R:Growth hormone
1 1 2 (b) Hormones Q stimulate the development of follicle in the ovary and spend in the testis. Identify
hormone Q
Follicle stimulating hormone (FSH) 1 1
(c) The presences of hormone Q causes the secretion or hormone Y which affect the development of uterus
Estrogen hormone
1 1
(d) The pituitary gland is known as \master gland .Explains why
F-Its secreted hormones which control the activities of other endocrine glands to secrete their hormones
E-FSH control the secretion of estrogens in ovary (or any other suitable examples)
1
1 2
(e)
P1 - because it secretes several hormones that control other endocrine glands P2 - for example, TSH is secreted to stimulate thyroid gland to release thyroxine //accept any correct hormones and their function
1 1 2 The pituitary gland is regarded as the “master “ endocrine gland.
The involvement of both the nervous system and the system in a ‘flight or fight’ situation
No Marking scheme Marks
(a) Diagram shows an emergency situation faced by Abu
Explain the condition between the system shown in diagram, 7.2(a) and 7.2(b) to respond toward the situation
P1 Stimuli is detected by hypothalamus
P2 Hypothalamus sends impulse through sympathetic nervous system to the effector / heart / respiratory muscle / blood vessel
P3 Hypothalamus send nerve impulse to adrenal medulla P4 Adrenal medulla secretes adrenaline and noradrenaline
P5 Both hormones are sent to target organ / heart / respiratory muscle /blood vessel through blood
P6 These two system cooperate each other P7 Causes increase in blood glucose level
P8 Causes blood vessel constrict to increase the blood pressure
P9 Causes respiratory muscle to contract and relax faster// increase breathing rate P10 Causes heart to pump faster // increase heart rate
P11 To transport more oxygen and glucose to the skeletal muscle & brain
P12 Brain more alert to mobilise body into immediate action /run away from the dog
1 1 1 1 1 1 1 1 1 1 1 1 10
No Marking scheme Marks (b) Diagram 7.2 shows the sequence of organs and tissue that responded when a man was attacked
by a robber
Explain the involvement of nervous system and endocrine system in this situation P1- The receptors / eyes detect stimulus
P2- Sent nerve impulse to brain
P3- Integration and interpretation of information P4- Sent nerve impulse to adrenal gland
P5- Secretes adrenaline
P6- Transported by blood (to liver, lungs and heart) P7- (In the liver,) glycogen converted into glucose P8- Increase breathing rate
P9- Increase ventilation rate // gaseous exchange in the lungs P10- Increase heartbeats
P11- More blood / glucose / oxygen (in skeletal muscles) P12- More cellular respiration
P13- More energy released
P14- For muscles contraction // To respond / fight back / run away
1 1 1 1 1 1 1 1 1 1 1 1 1 10 (c) When a man is chased by a fierce dog ,he is experiencing „flight or fight‟ situation
Explain how the nervous system nd the endocrine system of the man coordinate to respond to this situation
P1-the receptor in the eye detect the dog
P2-Nerve impulses are generated and transmitted to the brain via an afferent neurone P3-The hypothalamus in the brain is stimulated
P4-It actives the sympathetic nervous system to generate nerve impulses
P5-Nerve impulses are transmitted to the adrenal medulla to stimulate secretion of adrenaline P6-Adrenaline carried /transported by circulatory system to targeted organs
P7-Adnernaline promotes the breakdown of glycogen to glucose P8-(Adrenaline) increases the breathing rate
P9-More oxygen will be taken into the body
P10-(Adrenaline) increases the rate of heartbeat/blood pressure P11-Rate of the blood flow increase
P12-More glucose and oxygen will be supplied to the muscle P13-More energy produced by the muscles/metabolic rate increase
1 1 1 1 1 1 1 1 1 1 1 1 1
No Marking scheme Marks (d)
Explain how the endocrine system and nervous system both work together to bring about immediate response of the boy in the above situation
P1- Light enters the retina and the image of the fierce dog is formed P2- Nerve impulse s generated by the sensory nerves at the retina
P3- The nerve impulse are transmitted the brain /central nervous system to be analysed/interpreted
P4- Sound waves enter the cochlea in the ears
P5- The nerve impulse are generated and transmitted to the brain /central nervous system to be analysed /interpreted
P6- The hypothalamus is activated to send the nerve impulse to the adrenal medulla P7- Adrenal medulla secretes adrenaline into the blood stream
P8- Adrenaline will increase the metabolic rate P9- It stimulated the heart beat beat faster P10- And also breathing rate
P11- and increase the conversion of glycogen to glucose
P12- Finally send more oxygen and glucose to the brain and skeletal muscles
P13- The brain is highly alert to mobilise the various parts of the body for immediate action P14- The skeletal muscle become energised to flee immediately form danger to run away from
danger /to climb a big tree
P15- This reaction is celled fight-or-fight action
P16- These changes will prepares the boy to respond to the dangerous situation /threatening situation Any 10 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 10 (c)
Using your biology knowledge, explain how the endocrine and nervous systems coordinate the mother‟s response in such situation
When the mother sees her child under the car P1-the receptor in the eyes/retina detect the stimulus P2-and trigger a nerve/stimulus impulse
P3-a nerve impulse is sent /transmitted to the central nervous system (CNS)Spinal cord /brain /interneurone
P4-Through afferent neurone P5-Across a synapse
1 1 1
1 A mother and her young child were involved in an accident. The child was pinned under
their car. Upon seeing her child under the car to free her child
A boy saw fierce dog barking and running toward him .The boy ran away and finally climbed up the big tree
P11-More energy is produced
P12-for muscle contraction (hence, the mother is able to lift the car to free her child)
1 1
Explain the involvement of both the nervous system and the endocrine system in that critical situation.
P1 - The situation is called “fight or flight” situation
P2 - Nerve impulses from the eyes (receptors) travel to the brain P3 - The information is interpreted and the brain sends nerve impulses to the adrenal glands
P4 - The adrenal glands are stimulated to release adrenaline P5 - The hormone increases the heartbeat rate, blood pressure and blood flow to the muscle
P6 - The breathe become faster and deeper
P7 - metabolic activity and glucose level in blood increase P8 - The skeletal muscles become more energized and enable a person to fight off an attacker or flee immediately
1 1 1 1 1 1 1 1 6 3.4 Homeostasis in human
Aspect Marking scheme Marks
Definition What is meant by
(i) Internal environment
P1-(physical and Chemical) condition within our body P2-Extracellular fluid that surround our body cells
P3-Example are body temperature, blood glucose level, pH, blood osmotic potential and blood pressure
P1&any other P MAX 2 (ii) Homeostasis
P4-A process of maintaining internal environment/physical and chemical condition in our body at a constant value
P5-through corrective mechanism based on negative or positive feedback
P6-which revert the internal environment back to normal condition of there is a change P4& any other P MAX 2
1 1 1 1 1 1 4
Importance Explain the important of kidney in maintaining human health
P1-to eliminate waste product/urea/toxic waste/ excess salt water form the blood P2-to maintain the normal osmotic pressure in blood /constant internal environment P3-To maintain the optimal physical /chemical condition in the internal environment
1 1 1 3 After watching a horror movie at a cinema, Salim went back to his home. On
the way home, he saw a monster exactly the same as he watched in the movie. He was very shocked and frightened. So he ran away as fast as he could.
Aspect Marking scheme Marks The
nephron
N
Name the organ in the human body where the structure in Diagram 4 could befound?1 Kidney
1 1
Name the structure on right side Nephron
1 1 Name the processes that occur in parts inJ, K and M at the nephron3
J:Ultrafiltration K: Reabsorption M: Secretion 1 1 1 3 Name the Blood vessel P and Q
P: Renal artery Q: Renal Vein
1 1 2 State one difference in the content of P and Q in excretion
P has more nitrogenous waste product /urea/uric acid/salt than Q 1 1 Name two blood components found in renal artery but not in the part labeled J.
Red blood cell Plasma proteins
1 1 2 Suggest a reason for the component difference in above
Both components are large (to move through small pores in the capillaries wall and inner wall of bowman‟s capsule
1 1 : Bowman’s capsule
Loop of Henle: Distal convoluted tubule
Aspect Marking scheme Marks Ultrafiltration Name the process take place in J
Ultrafiltration 1 1
Describe the process mentioned above P1-Blood under high hydrostatic pressure
P2-Because the diameter of afferent arteriole is larger than efferent arteriole P3-force the fluid filtrate into capsule bowman‟s
P4-Form the glomerular filtrate
1 1 1 1 3 Explain the formation fluid J
P1-(by) ultrafiltration
P2-( due to ) hydrostatic force
P3-Some blood component except red blood cell platelet and plasma protein enter J 1 1 1 3 Reabsorbtion Explain what happen to the filtrate that flows from J to L?
From J to K where
F1 : Glomerular filtrate become more concentrated
El : Reabsorption of water into the blood capillaries by osmosis F2 : Glomerular filtrate does not contain glucose and amino acids E2 : Reabsorption of all glucose and amino acids by active transport into the blood capillaries
From K to L where
F3 : Glomerular filtrate has a higher concentration of urea
E3 : Urea not reabsorbed from filtrate but water reabsorbed from filtrate F4 : Glomerular filtrate low in salt
E4 : Reabsorption of sodium and chloride ions into blood capillaries by active transport 1 1 1 1 1 1 1 1 3
Explain why the glucose and amino acid can found in glomerular filtrate but absent in urine
P1-Because all the glucose and amino acid will reabsorb in the (proximal convoluted tubule)
P2-Through active transport
1
1 2 Different Explain one different between the content in fluid J an L
P1-In J /Bowman‟s capsule has higher glucose/amino acid/ vitamin/ minerals/ water// In F has lower glucose/amino acid/vitamin/minerals/water
P2-Because reabsorption occur in proximal convoluted fluid
1
1 2 Give the different between the content A(renal artery) and B (renal vein)
P1-Urea in A ismore compare in B
P2-Oxygen in A is more in A compare in B
1 1
Describe the urine formation.
Aspect Marking scheme Marks
P1 – The formation of urine involves three main processes : ultrafiltration, reabsorption and secretion
1 1 Ultrafiltration P1-(Blood enters the glomerulus),ultrafiltration takes place whereby the high
pressure forces fluid through the filtration membrane /glomerulus into capsular space/bowman‟s capsule
P2-The fluid is called glomerular filtrate
P3-Glomerular filtrate contains water/glucose/amino acids/irea/mineralslts/other small molecule but does not contain red blodd cells and plasma protein
P4-useful substance are reabsorbed (form the filtrate into the blood _while toxic compounds water /any solutes in excess are removed (as urine )
1
1
1
1
Reabsorption P5-in proximal convoluted tubule,sodium ions and chloride ions are pumped into capillary network
P6-reabsorbed of glucose and amino acids by active transport P7-in the loop of Henle ,water sodium ,chloride ions are reabsorbed
P8-at distal convoluted tubule and more water, sodium and chloride ions are reabsorbed
P9-at collecting duct ,99% of water has been reabsorbed (into blood stream )and 1% of water leaves the body as urine
1 1
1 1
1
Secretion P10-occurs at distal convoluted tubule
P11-waste/exces substances/hydrogen ions /potassium ions /ammonia/urea/creatine /toxin /drug are eliminated
P12-by adjusting the amount of ions the kidney regulate the chemical composition ./water content any10-\
1 1
Essay enhancement corner
No Marking scheme Marks
(a) Diagram 12.3 shows a part of a nephron structure.
Label and complete Diagram 12.3 above. State the role of a nephron. D-1 L-1
P1 - A nephron is a basic structural and the functional unit of the kidney P2 - It is responsible for the actual purification of blood in producing urine
2 1
1 4 (b) Base on the Table 6.2, explain why the concentration of solutes in the plasma, glomerular
filtration and urine of the adult are differ.10
Describe the formation of the glomerular filtrate
E1 : When blood enters the glomerulus, ultrafiltration takes place
E2 : because blood from the aorta reaches the nephron/glomerulus at high pressure
E3 : and due to the different between the diameter of the afferent arteriole and efferent arteriole E4 : The high pressure forces fluid through the filtration membrane into capsular space forming glomerular filtrate 1 1 1 1 4 Bowman’s capsule Proximal convoluted tubule Loop of Henle Distal convoluted tubule Collecting duct
No Marking scheme Marks (c)
Base on Diagram 6.1 , describe briefly the formation of the glomerular filtrate 4 Process Y = ultrafiltration
A process whereby
F1 – water and solutes from glomerulus being forced to filter through the membrane of Bowman‟s capsule
F2 - by the high hydrostatic pressure
F3 - forming glomerular filtrate that contains water, glucose, amino acids, urea, mineral salts and other small molecules
1
1
1 1 4
(d) Diagram shows the structure of nephron in the human Kidney
Explain the process that occurs at P 4 F1-Ultrafiltration (process take place)
E1-Diameter of efferent arteriole is smaller than afferent arteriole
1 1
No Marking scheme Marks (e) Table 6 .2 shows the concentration of solutes in the blood plasma, glomorular filtration and
urine of an adult.
Solute Concentration of solutes (g/dm3)
Blood plasma Glomerular filtrate Urine
Glucose 1.0 1.0 0.0
Amino acid 1.5 1.5 0.0
Protein 80.0 0.0 0.0
Urea 0.3 0.3 20.0
Sodium ion, Na+ 3.2 3.2 1.6
Diagram 7.1 shows part of the circulatory system and a nephron in human kidney. F1 – Glucose reabsorb by facilitated diffusion into blood capillary
E1 – Glucose needed by our body
F2 – Acid amino reabsorb by facilitated diffusion
E2 – Acid amino is needed for body growth / tissue repair
F3 – Protein is a big molecule and cannot move via membrane plasma. E3 – Protein is still circulate in blood capillary.
F4 – Urea is secreted substances and cannot move back to blood capillary E4 – Water is reabsorb by osmosis and the concentrate of urea increase. F5 – Sodium ion is move back to blood capillary via active transport E5 – Sodium is importance for maintain the blood pressure.
1 1 1 1 1 1 1 1 1 1 10 (f) Table 7.1 shows the concentration of solutes in the blood plasma, glomerular filtrate and urine
of an adult.
Based on Table 1, explain why the concentration of solutes in the blood plasma, glomerular filtrate and urine of the adult are differ.
F1 : Concentration of glucose / amino acid / urea / sodium ions in the blood plasma and
the glomerular filtrate E2 : through ultrafiltration.
E3 : Able to pass through the wall of blood capillaries / Bowman‟s capsule. F2: No glucose / amino acid in the urine.
E4 : All glucose / and amino acid are reabsorbed from the proximal convoluted tubule / nephron
E5 : by facilitated diffusion / active transport into the (peritubular) capillaries // blood capillaries
F3 : Less sodium ions in the urine than in the blood plasma / glomerular filtrate.
E6 : Some sodium ion have been reabsorbed from the Nephron (by active transport into the peritubular capillaries // blood capillaries)
F4 : No protein in the glomerular filtrate / urine. E7 : They are large molecules.
E8 : Unable to pass through the wall of blood capillaries / Bowman‟s capsule. F5 : Very high content of urea in the urine.
E9 : Secretion of urea into the nephron at the distal convoluted tubules Any ten points
1 1 1 1 1 1 1 1 1 1 1 1 10
(g) Table 3 shows the concentration of some substances in the blood plasma. glomerular filtrate and urine of an adult.
Substances in fluid Concentration of substance in fluid Blood plasma
entering the glomerulus
Glomerulus filtrate Urine produced kidney Glucose 1.0 1.0 0.0 Amino Acid 1.5 1.5 0.0 Protein 80.0 0.0 0.0 Urea 0.3 0.3 20.0 Sodium ion 3.2 3.2 3.3
Based on 'l'ablc 3, explain the difference in the concentration of urea in the blood plasma, glomerular filtrate and urine.4
F1 Concentration of urea in blood plasma is 0.3 g/dm3 which is same as in glomerular filtrate El : Ultrafiltration in Bowman's capsule
E2: High pressure of blood forces out fluid from blood plasma Contain urea and other solutes
1 1 1
No Marking scheme Marks (a) Table shows the cmposition of human blood and urine
Chemical substances Percentage in blood % Percentage in urine%
Water 97 95
Plasma membrane 8 0
Glucose 0.10 0
Urea 0.03 2.0
Explain the differences between the percentage od chemical substances in blood and urine 10 F1-Percntge of water in blood is higher than in urine
P1-In the proximal convuluted tubule
P2-The Na + are pumped into the capillary//some salts are reabsorbed by a active trasnport P3-The movement os solutes into the capillary network decrease the solute concentration in the capillary Network
P4-As a result, water diffuse into blopod capillaries by osmosis from the proximal convuluted tubule/loop of Henle /diatal convuluted tubule /collecitng duct
F2-Percentage of plasma protien is higher in blood compared to urine //percantage of plasma protien is nil in urine
P5-Size of plasma protiens are larger /too large which cannot be filtered out diffused out during ultrafiltration
F3-Percentage of gluscose is high in blood but nil in urine
P6-All glucose are reabsorbed by active transport at proximal conculuted tubue F4-Percentage of Urea is higher in urine than in blood
P7-Urea is actively transported from the blood capillary to the distal onvulted tubule P8-By active secretion process
F5-Urea is filtered but not reabsorbed into then blood
P9-selctive reabsorbption Any 10 1 1 1 1 1 1 1 1 1 1 1 1 1 10
No Marking scheme Marks (b) Table shows the content of component in R and S in Diagram
Based on the table
Explain why the content of R and S are different 10 F1-Glucose /oxygen present in the R and s
E1-There is high hydrostatic pressure at the arterial and of the capillaries E2-Glucose .oxygen force out form the R to S
E3-able to pass through the wall of blood capillaries F2-No albumen /platlets/erthrocyres in the S
E4-Large molecule .components
E5-Unable to pass through the capillary wall F3-Leucocytes present in the R and S
E6-because leucocytes ooze through the opening in the capillary wall F4-Urea present in the R and S
E7-Diffuse form the body cells through the into R any 10
1 1 1 1 1 1 1 1 1 1 1 10
(c) In a study carried out, an individual X drinks a glass of glucose solution. Table 4.2 shows the changes in the concentration of blood glucose in individual X
The role of kidney in homeostasis
No Marking scheme Marks
(a)
What is the function of osmoregulation ?
E1-Kidney regulate salts /solutes and water level in the blood
E2-To maintian a constant water potential in the body/regulates the osmotic pressure of the blood
1 1
2 (b) Explain the consequence of kidney failure
P1-The blood osmotic pressure and blood volume cannot be maintianed P2-Leads to the accumulatioon of toxic waste and excess minerals in the body
1 1 2 (c) Indivudul Y drinking excess water
State the blood osmotic pressure after drinking excess water
Osmotic pressure in plasma prouten decraese//water potential increase 1 1 (d) Epxlain Hypothalamus and gland M response to the condition after drinking excess water
Hypotalamus
E1-Osmoreceptor (in hypotalamus ) detect the chnge /less stimulated Gland M:
E2-Pituitary gland /galnd M is less/not stmulated /trigger E3-Hence less hormone P/ADH secreted
E4-Less water reabsorbed
1
1 1 1 4
No Marking scheme Marks (e) If individul Y consume food which high in salt, adrenal gland will secreted hormone Q
State the hormone Q
Hormone Q: Aldosterone hormone
Kidney function may e impaired by excessive blood loss,vcertain piosons or infection disease which can lead to kidney failure
1 1 2
(f) Explain the effects if more antidiuretic hormone (ADH) is secreted to the targeted organ as shown in the diagram 3
E1-More ADH will increase the permeability of distal; convoluted tubule and collecting duct E2-More water is reabsorb into the blood capillary
E3-Urine become less and more concentrated
1 1 1 3 (g)
Explain how the machanism of hormone Q to restore the osmotic prssure back to normal level E1-(adrenal gland less stimulated ),Less aldosterone nproduced
E2-Less salt is reabsorbed /most of it will be secreted though urine
1 1 2
(h) Explain the effects of drinking a large amount of water on the quality and quantity of the urine of a healthy person.4
F : More urine is produced and more dilute/ less concentrated
El: Blood osmotic pressure drops below normal range osmoreceptors in hypothalamus less stimulated
E2: less antidiuretic hormone secreted from pituitary gland
E3: Distal convoluted tubule and collecting duct less permeable to water E4: Less water is absorbed into the blood
E5: Aldosterone from adrenal gland cause reabsorption of , sodium ions in blood
1 1
1 1 1
P4-Less water will be absorb by the tubule thus
P5-Osmotic pressure of blood increase back to normal pressure OR
P1-If blood osmotic pressure higher than normal level, It can be detected by osmoreceptor cell in hypothalamus
P2-Hypothalamus will produce less ADH (and send to kidney)
P3-Cnvulted tubule and collecting duct become more permeable to water P4-more water will be absorb by the tubule thus
P5-Osmotic pressure of blood become normal again
1 1 1 1 1 1 1 3 (j) Discuss the effects of drinking a large amount of water on urine.2
P1-Osmoreceptor in the hypothalamus is less stimulated, less ADH hormone is secreted P2-The distal tubule and the collecting duct are not permeable to water
P3-Less water is absorbed in the blood
P4-A large amount of urine is produced, making it dilute
1 1 1 1 2 Essay enhancement corner
Aspect Marking scheme Marks
Osmo -regulation
Process
Diagram shows human kidney
Describe the role of hormone in regulation of blood osmotic pressure by kidney 10 When someone takes more salt in his meal:
P1-Increase in blood osmotic pressure is detected by the receptor P2-Rceptor triggers impulse
P3-and the impulse are sent to pituitary gland
P4-Pituitrary gland secretes ADH into the blood stream
P5-ADH stimulates the wall of distal convoluted and collecting duct to become more permeable to water
P6-Water will be reabsorbed into the blood stream P7-Blood osmotic pressure decrease back to normal
1 1 1 1 1 1 1 1 When Blood osmotic pressure of a person decrease
P8-when his drink too much
P9-Adrenal gland at kidney wil be stimulate to serrate aldosterone tubule and collecting duct to become preamble to slat
P11-Salt will be absorbed into the blood stream
1 1
Aspect Marking scheme Marks Osmo
-regulation Process
Describe the process at Q in osmoregulation of blood osmotic pressure E1-when the osmotic pressures of blood decrease, the osmoreceptor cells in the hypothalamus are detect the change
E2-The pituitary gland is not secreted ADH /Adrenal gland stimulated to released aldosterone
E3-Less water reabsorbed .more salt reabsorbed
E5-When the osmotic pressure of blood increases. The osmoreeceptors cell in the hypothalamus are detect the change
E2-The pituitary gland is secreted ADH /Adrenal gland not stimulated to released aldosterone
E3-Causes the structure Q /collecting duct to become permeable to water/not permeable to salts
E4-more water reabsorbed/no salts reabsorbed
1 1 1 1 1 1 1 6 Describe how the structure of the kidneys is adapted to enable them to play a role
inhomeostasis
F1-(each kidney) contains hundreds of thousand/a large number of nephrones /nearly oen million nephrones
P1-To filter substance form the blood efficiently F2-(each kidney) has ureter
P2-to carry away the urine /solution of waste dissolved in water /creatinine/toxin and drugs
F3-(each kidney)has rich capillary network
P3-Ultrafiltration /reabsorption can take place efficiently
F4-Has Bowman‟s capsule.Proximal convoluted tubule /loop of Henle/distal convoluted tubule /collecting duct
P4-Ultrafiltration /reabsorption /secretion
1 1 1 1 1 1 1 1 6
Diagram 7.1 shows the negative feedback mechanism in regulating the water balance in human blood.
P1- Water content in the blood is low // Blood is hypertonic P2- Detected by osmoreceptor
P3- In hypothalamus
P4- Send nerve impulse to pituitary gland P5- Secretes ADH
P6- Transported by blood to kidney
P7- Distal convoluted tubule / collecting duct of nephron P8- More permeable towards water
P9- More water reabsorbed by blood (and less urine produced)
1 1 1 1 1 1 1 1 10
A man takes too much salty food during lunch .His urine becomes less and concentrated.Epxlain why4
F-Blood osmotic pressure increase
P1-Detected by osmoreceptor in hypothalamus P2-impulse is sent to adrenal gland and pituitary gland
P3-Adrenal gland secrete les aldosterone and pituitary gland secretemore ADH P4-Cell lining of distal convulted tubule and cd less premeable to salt and more premeable to water
P5-Less reabsorption of salt and more reabsoorption of water into blood vessel
1 1 1 1 1 1 4 Kidney failure
En. Kamal was informed by his doctor that his left kidney fail to function.By using your biology knowledge, explain the effect of his kidney failure on his health and give a suggestion to overcome this problem6
F1 - less efficient in filtration of waste products and excess water in blood plasma P1- as a result, urea uric acid/ creatinine / salt concentration will be increase P2 - increase the blood pressure
F1 - use haemodialysis machine / kidney transplant
F2 - to replace the function of kidney; filtrate all the waste product and excess water
1 1 1 1 1 6 En Hamah was informed by his doctor that his left kidney fail to function .By using our
biology knowledge, explain the effect of his failure on his health d give a suggestion to overcome this problem
F1-less efficient in filtration of waste product and excess water in blood plasma P1-As a result urea, uric acid/creatinine/salt concentration will be increase P2-Increase the blood pressure
Suggestion:
F1-Use haemodialysis machine /kidney transplant
F2-to replace the function of kidney; to filter all the waste product and excess water
1 1 1
1 1 5 Explain the condition of the patient before undergoing this treatment (Haemodialysis)
F1-the kidneys are malfunction /stop function /kidney failure
P1-Blood contains of high amount of waste materials/Urea/toxic waste/salts P2-Blood constituents/osmotic pressure higher than normal
1 1 1 3
If the kidney is severe enough and the patient does not want want to use dialysis machine ,give suggestion of treatment and explain briefly about the treatment F1-Kidney transplant
Aspect Marking scheme Marks Dialysis Diagram shows a simplified version of a kidney dialysis machine
State the definition of Haemodialysis
F1-Filtering blood using artificial kidney/kidney machine means that replace a failed kidney
1 1
Describe how the, machine is used to remove waste product such as urea form a person with kidney failure
P1-Blood form the patient vein is passed though a machine P2-Which contains a dialyser /dialysis solution
P3-Dialysis tubing has a semi –premaeble membrane
P4-concentration of waste molecule /urea in blood is higher than in the dialysis s0olution //there is concentration gradient between the blood and dialysis solution P5-waste molecule /urea/excess salts diffuses through membrane form blood to dialysis solution
P6-Dialysis solution is continuously being replaced //essential substances remain in the blood
P7-Plasma protein /red blood cells are not able to diffuse through membrane of dialysis tubing
P8-Because the size is bigger /too big
P9-The direction of the flow of blood is opposite to the direction of dialysis solution P10-To ensure the waste molecule /urea is continuously being removed form the blood to dialysis solution 1 1 1 1 1 1 1 1 1 6 Explain briefly how the machine functions
E1-A patient blood‟s passed/converted through (several) narrow/series of tubes E2-Made of a partially-permeable dialysing membrane
E3-The pores in the dialysing membrane allow small particles such as glucose/ions/urea to pass through
E4-but not big particle such as blood cells /plasma proteins E5-The narrows)tubes are immersed in a dialysis fluid
E6-Dialysis fluid ,which has a same composition as tissue fluid
E7-the dialysis fluid contains glucose and ions but not waste products such as urea E8-As useful substances are present in equal concentration s occurs
1 1 1 1 1 1 1 1
The regulation of blood sugar level
No Marking scheme Marks
The regulation of blood sugar level
Name organ Z Pancrease
State Hormone X and Hormone Y secreted by organ z Hormone X: glucagon
Hormone Y: insulin
A man found that his urine shown positive result when tested with Benedict solution State the health problem faced by the man mentioned above
Diabetes mellitus
Khairi suffers form diabetes insipidus produces a large amount of urine .Explain how this problem is related to the imbalance of hormone in his body2
P1-Lacking in ADH /antidiriuretic hormone
P2-Less absorption of water in the distal convoluted tubule/collecting duct//distal convoluted 1 1 1 1 1 1 2 1
No Marking scheme Marks (a) The adult later suffers from diabetes but does not take his regular injection of insulin.
Explain the changes that might occur to the content of his urine and suggest a laboratory experiment to confirm the content of the urine
Able to explain changes that might occur to the content of the adult’s urine. E1 : excess glucose is found in his urine
E2 : glucose cannot be converted into glycogen
E3 : Excess glucose will not be reabsorbed from the nephron // proximal convoluted tubules E4 : into ( peritubular) capillaries // blood capillaries
Any three points
Able to suggest a laboratory experiment to confirm the content of the urine F1 : (The laboratory experiment to be conducted) is the Benedict‟s test.
P1 : (In a test tube) , add about 1 ml of urine sample with 1 ml of Benedict‟s solution P2 : The mixture is heated (in a water bath) for 5 minutes
P3 : Observe the presence of brick red precipitate to confirm the presence of glucose in the urine
Any three points
1 1 1 1 1 1 1 1 6 (b)
Diagram 6.1 shows the negative feedback mechanism that regulated the blood glucose level in human being
(i) Explain briefly the meaning of negative feedback‟ mechanism
P1-It is corrective mechanisms (which reverses the original change and bring the system back to the normal
P2-When the blood glucose level decreases, It will increase and finally back to normal /vice versa
(ii) Describe how the hormones X and Y regulate the blood glucose level in humans P1-Hormone X and Y produced by pancreas
P2-Hormone X /glucagons is secreted by alpha cells whereas hormone Y /insulin is secreted by Beta Cells
P3-If the blood sugar level is lower than normal,more hormone X /glucogon is secreted 1 1
1 1 1
No Marking scheme Marks
(c) Homeostasis is the maintenance of constant internal environment.The blood normal sugar concentration in human is 75-110mg/100ml 10
P1-(The islet cells in the )pancreas secretes insulin P2-and glucogon
P3-directly into blood stream
P4-if the blood levl increase/more than 110 mg /100 ml ,insulin convert excess glucose to glycogen
P5-in the liver
P6-insulin stimulate uptake of glucose by liver/muscle /adipose cell for respiration P7-for cell respiration //to obtain energy
P8-Blood sugar level decrease to normal range
P9-if blood sugar level degrease/less than mg/100ml, glucagon convert glycogen to glucose P10-Glucagon promotes lipid breakdown
P11-torlease fatty acid /energy
P12-blood sugar level increase to normal range any 10
1 1 1 1 1 1 1 1 1 1 1 1 10 (d) Explain how the body of a healthy person restores the blood sugar level to normal if the level
drops too low.
P1 - The islet cells in the pancreas are stimulated to release glucagon P2 - Glucagon stimulates the liver to break down glycogen to glucose P3 - This restores the blood sugar level to normal
P4 - Glucagon also promotes lipid breakdown
P5 - This releases fatty acids that can be metabolized to generate energy P6 - This restores the blood sugar level to the normal range
1 1 1 1 1 1 1 6
The regulation of body temperature
No Marking scheme Marks
(a) A worker enters a cold room that stores frozen meat. Explain how the regulation of the worker body temperature occurs 6
P1-When the environment is too cold, the stimuli is detected by receptors I the skin P2-Impulse is sent to brain /hypothalamus
P3-Hypothalamus sent impulse to the effectors
P4-Vasoconstraction of arterioles in the skin, Less blood flows to the skin P6-So less heat is lost (to surrounding)
P7-Erector muscle contract. Hairs raise up so trap more heat
P8-Adnernal gland secrete adrenaline whereas thyroid gland secretes thyroxin to increase metabolic rate
P9-shivering takes place, this results in increased the production of heat
1 1 1 1 1 1 1 1 1 6 (b) Diagram 4.3 shows a person who is sweating under a hot sun
State what will happen to his blood osmotic pressure in the person‟s body. The blood osmotic pressure increases
Explain how gland Q involves in returning the osmotic pressure of the blood to normal levels.3
P1 : The osmoreceptor detects the increase in the osmotic blood pressure P2 : Gland P is stimulated to release more ADH
P3: ADH is transported by blood to the kidneys
P4 : ADH increases the permeability of the wall of distal convoluted tubule and collecting ducts
P5 : More water is reabsorbed from the filtrate into the blood
1 1 1 1 1 1 1 3
No Marking scheme Marks (c) Diagram 7.1, 7.2,7.3 and 7.4 shows four different environmental conditions.
Describe the regulatory mechanism carried out to maintain the body temperature at 36.7 in both condition above. 6
Hot Condition
F1-erector muscle relax so that hair is lowered P1-A Thin air is trapped by the hair
P2-Heat can be lost easily
F2-Blood capillaries in the dermis of the skin dilate//Vasodilation P3-More blood flows near surface of skin
F3-Sweat glands secrete sweat actively
P4-When sweat evaporates,It absorb heat from the skin F4-Less thyroxine and adrenaline are produce
P5-Body„s metabolic rate decrease//Less heat is generated within the body 4 F & Corresponding P
Cold condition
F1-Erecvtor muscle contract so that hair is raised P1-A thick layer of air is trapped by the hair
P2-THhe layer of air acts as an insulator to prevent loss of heat form the body F2-Blood capillaries in the dermis of skin constrict//vasoconstriction
P2-Less blood flows near the surface of the skin F3-Skeletal muscle contract involuntary //shivering P3-Genertaes heat to raise the body temperature F4-More throxine and adrenaline are secreted
P4-Body‟s metabolic rate increase//more heat is generated 4F&corresponding P 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 6
No Marking scheme Marks (d) Diagram shows the organ involvees in homeostasis
Does the organ shows in diagram 9.2 can regulate the human body temperature? Give your reason
Evaluate: yes
Reason:When the body temperature falls
F1-(cold) receptors/thermoreceptor detects the change of the body temperature falls E1-Afferent neurone transmitted the nerve impulse to the hypothalamus
E2-Hypothalamus acts as the temperature regulatory centre
E3-Nerve impulse is transmitted form the hypothalamus to the skin (by efferent neurone to produce response by negative feedback mechanism)
F2-Hairs erector muscle are stimulated to contract E4-Hiars become erect
E5-A thick layer of air is trapped
E6-Less hest loss (to the environment by radiation /conduction n) F3-Sweat glands inactive
E7-Less sweat produced
E8-Rate of evaporation (very ) low E9-Heat is conserved
F4-Vasoconstriction occurs //blood vessel constrict E10-Less blood flows close to the body surface E11-Heat loss (by radiation/conduction )is reduced E12-Body temperature increase back to normal any 9OR When the body temperature high
F1-(warm) receptors/thermoreceptor detects the change of the body temperature high E1-Afferent neurone transmitted the nerve impulse to the hypothalamus
E2-Hypothalamus acts as the temperature regulatory centre
E3-Nerve impulse is transmitted form the hypothalamus to the skin (by efferent neurone to produce response by negative feedback mechanism)
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
E9-Heat is lost form the skin .colling the skin F4-Vasoconstriction occurs //blood vessel dilate E10-More blood flows close to the body surface E11-Heat loss (by radiation/conduction )is incraesed E12-Body temperature decrease back to normal any 9
1 1 1 1 1 10 (e) Diagram shows the mechanism of thermoregulation in human
Based on diagram, explain how the mechanism of thermoregulation acts10
M1-Changes in the environmental temperature are detected by thermoreceptors in the skin //changes in the blood temperature are detected by thermoreceptor in the hypothalamus M2-These thermoreceptors transmit nerve impulse to the thermoregulation centre in the hypothalamus
M3-The hypothalamus/thermoregulation centre sends nerve impulse /electrical signals to the effectors
F1-smooth muscle in the arterioles in the skin rlax ,causing vasodilation
E1-More blood is carried to the surface of body, where heat is loss by convection and radiation F2-The sweat glands secrete sweat onto the surface of the skin where it evaporates
Water has a high latent heat of evapoeration ,so this process takes heat from the body and the body cools
F3-the hairs erector muscles relax, lowering the skin hairs
E3-only a thin layer of air is trapped between the hairs. Heat lost through conduction and radiation is increased
F4-The skeletal muscle do not contract and relax involuntarily E4-there is no shivering and no unnecessary generation of heat F5-The adrenal gland /thyroid glands secrete less adrenaline /thyroxine
1 1 1 1 1 1 1 1 1 1 1
No Marking scheme Marks (f) Diagram shows a cross section of human ski n in two condition X and Y
Based on the diagram,
(i) State the condition Z an Y Condition X:
Cold condition //low temperature//any suitable example condition low temperature Condition Y:
Warm condition //high temperature//any suitable condition of high temperature
(ii) Explain how the arteriole responds to both condition 8 Condition X
E1-The smooth muscle around the arteriole contract/vasoconstriction occurs E2-the decrease the amount of blood flowing through the skin
E3-The arteriole is located further away form skin surface E4-Reducing the heat lost (by radiation /conduction) via surface
Condition Y
E1-The smooth muscle around the arteriole relax /vasodilation occur E2-this increase the amount the mount of blood flowing through the skin E3-the arteriole is located near the skin surface
E4-Increasing the heat lost ( by radiation /conduction via blood)
1 1 1 1 1 1 1 1 1 1 10 (g) Explain how the above effectors involved in the regulation of temperature
Sweat gland
P1-Sweating does not occur body heat is covered
Erector muscle P2-contracts
Hairs
P3-hiars is raised to trap an insulating layer/heat
1
1
No Marking scheme Marks (h) Figure shows a thirsty athlete who has just completed a 5 Km run
Explain how osmoregulation takes place in her body 10 E1-Running cause an increased in body temperature E2-sweating occurs to reduce body temperature
E3-Lost of water form the body increase the blood osmotic pressure E4-increase osmotic pressure detected by osomoreceptors
E5-in hypothalamus of brain
E6-Pituitary gland s stimulated to secrete Antiduiretic hormone (ADH) E7-ADH is transported by blood to the kidney
E8-ADH increased the permeability of the distal convoluted tubule and collecting tubule to water
E9-Reabsorbtion of water increased in both tubules E10-Increase in water reduced the blood OP
E11-Medulla oblongata is also stimulated to produce a feeling of thirst
1 1 1 1 1 1 1 1 1 1 1 10 3.5 Practicing a healthy lifestyle
No Marking scheme Marks
(a) Drug can later brain function and the rate at which neuron release neurotransmitters .These are different types of drug which are stimulus depressants. There are different types of drug which are stimulants,depressants,hallucinogens and narcotic
Based on the statement, state and explain briefly the effect of any two drugs Drug -1 Effect-1
Type of drug Mark scheme Stimulants D1-cacine
E1-Block the removal of pleasure-inducing neurotransmitters Depressants D2-Transquiliser
E2-slow down the transmission of impulses Hallucinogens D3-LcD
E3-cause user to see, hear and perceive things that do not exist Narcotic D4-Herion //morphine
E4-Induce felling of euphoria/block pain signals/slow down
1 1 1 1 1 1 1
No Marking scheme Marks (b) Drugs and alcohol are being widely used on everyday life
Write evaluation report concerning the above statement Able to state advantages of drugs in medical:
F1-Produce medicine /pill
F2-steriod drug used by sport athlete
Reject:
1. used in producing cheese/yogurt 2. beer.wine
3. produce vinegar
Advantages Drug in human physiology F3-Depressant-psychiatry
F4-Depressant to relief pain
Advantages Alcohol used in life F5-production of perfume F6-Used in medical as antiseptic
Disadvantages used of drugs in human life
F7-Intrfere nervous system leads to lengthen reflex time F8-Liver failure/cirrhosis
Disadvantage of alcohol on human physiology F9-alter brain function
F10-Impair vision, coordination
Analyse skill: able to state at least two point of advantages and disadvantages
Evaluate skill: able to rationalize/justify whether drugs and alcohol give good impact or not to human 1 1 1 1 1 1 1 1 1 1 10
3.6 Plant Hormones
No Marking scheme Marks
(a) Diagram shows an experiment to study the effect of chemical substances T in coleoptiles towards the plumule growth of a plant
Name the chemical substance T in coleoptiles of the plant‟s seed
Auxin 1 1
(b) State another one part in plant where chemical T can be found
Root tips/young leave/embryo in seed 1 1
(c) In Another experiment, a group of student have removed the coleoptiles of a seed and placed it on agar block before placing it back on the cut plumule as shown in diagram
Draw a possible observation for the growth of plumule in the box in diagram 4.2 1 1 1 (d) Explain how chemical substances T named in (A) causing observation as drawn in above
E1-Chemical substance t /auxins produced in the coleoptiles tip dissolve into agar-agae block E2-Then dissolve in the removed bud tip tissue
E3-Stimulate elongation of Plumule
1 1 1 2
In another experiment, the shoot tips of young pea seedling with chemical substance T while another shoot tips acts as control. All shoot tips are incubated over a period of 48 hours .The results are shown in diagram
Based on the graph explain the difference between the treatment of chemical substance T and the control on the shoot tips 2
E1-The mean length of the treatment shoot tips at the end of 48 hours is longer than the control shoot tips
E2-Becuase the rate of elongation is higher with the present of chemical substance T /auxin
1
1 2
Essay enhancement corner
No Marking scheme Marks
(a)
Explain the mechanism involved in 10 Positive Phototropism of shoots
P1-When a shoot is exposed to light form one direction ,auxins whch are produced in the shoot tip
P2-Move into the zone of elongation
P3-At the zone of elongation .mnore auxin move to the shaded side away from the light P4-Resulting in a higher concentration of auxins in the shaded region than in the region exposed to light 1 1 1 1 1 1 Tropism involves the growth movement of certain parts of the
P10-Ahigh concentration of auxin in the root inhibits elongation of cells
P11-Hence the cell on the lower side of the root gro slower than the cell on upper side P12-As a result, the grows and bends downwards, toward the pull of gravity Any 5
1 1 1 10 (b) (i) Explain the terms phototropism and geotropism.
Phototropism
P1 – growth movement/ growth of plants towards light P2 – growth towards a source of light is called positive phototropism
P3 – growth away from the source is termed negative phototropism
1 1 1 Geotropism
P1 – The response of plants towards gravity P2 – The root shows positive geotropism. P3 – The shoot shows negative geotropism
1 1 1 4 (c) Beside stimulating the shoot elongation ,chemical substance T also has other function .Explain
how chemical substances t being used in :
(i)Propagation of plant through stem cutting method
E1-Chemical substance T /auxin stimulate growth of adventitious roots form the stem E2-This will promotes the growth of nw plants form the stem cutting
(ii)Parthenocarpy
E1-Treat flowers that hav not been pollinated with substance T auxin
E2:This will induc the development of fruit without fertilization (Parthenocarpy)
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4
(d) A mango farmer picked ten basket of immature mangoes for sale .Give one suggestion to make all the mangoes ripen on the same time1
Keep the upripe mangoes together with ripe fruit /bananas//spray the unripe mangoes with ethylene
Diagram 4.1 shows the effect of light on the growth of the pant shoot
Name the type of response of the plant shoot toward light Describe the response
Type of response: Tropism/phototropism Description:
P1-The plant shoot grows/bends P2-Toward light
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No Marking scheme Marks (a) Diagram 4.shows the direction of growth of the plumule and the radical of a seedling which is
placed in a horizontal position during germination Explain why
(i) The plumule grows toward direction X
E1-Auxin stimulates/promotes cell elongation at the shoot (tips)
E2-More auxin is distributing at the darker /lower side of the shoot (tip compring to the bright/upper side)
E3-(so at the darker /lower side ) the rate of cell elongation is higher (than the bright /upper side)
E4-The shoot (tips)grows/bends toward light /away form gravity
(ii) the radical grows toward direction Y
E5-(High concentration of) auxin inhibits cell elongation at radical/root( tip)
E7-More auxin is distributed at the lower /darker side of the root (tip comparing to the upper /brighter side)
E8-So the root grows/bends downward toward gravity/away form light
1 1 1 1 1 1 1 6 (b) State one difference in the role of auxin in shoot tips compared to root tips1
P1-At shoot (tips, high concentration of ) auxin stimulates cell elongation ) but at root
tip)auxin inhibits cell elongation 1 1
(c) Explain one importance of the response to the plant F1-Positive phototropism //negative Geotropism
E1-Enables the plants to receive maximum amount of sunlight for photosynthesis//any suitable explanation
OR
F1-Negative Phototropism//Positive Geotropism
E1-Enables the root (Hairs) to absorb nutrients/mineral salts from the soil//any suitable explanation
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(d) Diagram shows the direction of growth of plumule and the radical of a seedling which is placed in a horizontal position during germination
