Chapter
7
Locomotion and Movement
SECTION - A
School/Board Exam. Type Questions Very Short Answer Type Questions :
1. Mention the monomeric protein which polymerises to form myosin protein? Sol. Meromyosin.
2. Which cell organelle, present in sarcoplasm stores calcium? Sol. Sarcoplasmic reticulum.
3. How many forms of actin molecules are present? Name them.
Sol. Actin molecule occurs in two forms– G actin and F actin. Monomeric G-protein and polymeric -F protein. 4. Which joint is present in wrist?
Sol. Gliding joint.
5. Name the oxygen-storing pigment present in the red muscle fibres? Sol. Myoglobin.
6. Name the small vestigial bone present in the vertebral column? Sol. Coccyx.
7. Name the connective tissue that attaches bone to bone. Sol. Ligament.
8. What is the main cause of tetany?
Sol. Low level of calcium ions in the extracellular matrix which causes hyper excitation of muscles. 9. What is gout?
Sol. Type of arthritis where monosodium urate crystals deposit in the joints and cause inflammation. 10. Name the cell that forms the muscular tissue.
Sol. Myocytes.
Level - I
Short Answer Type Questions :
11. Write the unique properties possessed by muscles. Sol. Contractility, excitability, elasticity and extensibility. 12. Troponin is a trimeric protein. Explain.
Sol. Troponin is a trimeric protein because it is made up of three units such as (i) Troponin I– Inhibits actin-myosin interaction
(ii) Troponin T– Binding site for tropomyosin (iii) Troponin C– Binding site for calcium. 13. Why is matrix of bone hard and rigid? Sol. Due to the presence of calcium salts.
14. What do you understand by neuromuscular junction?
Sol. The junction between the nerve fibre and muscle fibre is called neuromuscular junction. 15. Define motor neuron.
Sol. The neuron that innervates the muscle and transmits a signal to the muscle fibre for initiating the muscle contraction is called motor neuron.
16. Schematically name the different types of movement. Sol. Movement Muscular movement Amoeboid or pseudopodial movement Ciliary movement
17. The movement of internal organs is essential. Give reasons and examples to support the above statement. Sol. The movement of internal organs is essential for several reasons:
(i) The food from the mouth moves to the stomach for digestion through the peristaltic movement of the oesophagus.
(ii) The pumping of heart is essential for circulation of blood to different parts of the body. 18. Draw a well-labelled diagram of monomeric unit of myosin.
Sol. Actin binding sites
ATP binding sites
Head
19. What is muscular movement?
Sol. The movement produced due to the contraction and relaxation of muscles is called muscular movement. 20. Explain the joint which causes movement only in two directions.
Sol. Angular or ellipsoid joint causes movement only in two directions. It is a type of joint in which articulate end of the one bone is oval or convex and the articulate end of the other is elliptical or concave. The oval or convex end fits into the elliptical or concave end and cause movement only in one direction i.e., back and forth. 21. How does movement occur in cartilaginous joint?
Sol. The movement occurs in cartilaginous joints due to the compression of the disc or pads of cartilage present on the articulated surfaces or ends of the bone taking part in the joint.
22. Based on location, how many types of muscles are there? Name them.
Sol. Based on location there are three types of muscles– skeletal muscle, smooth muscle and cardiac muscle. 23. What do you understand by the property of contractibility?
Sol. The property of shortening and then returning to relaxed state is called contractibility. The movement in limbs is caused by the contraction of muscles surrounding it.
24. Describe the protein which runs along the entire length of actin filament.
Sol. Tropomyosin is a fibrous molecule. The two filaments of tropomyosin run along the entire length of actin. It binds to the binding site of myosin on actin and hence separate actin and myosin, which in turn prevents the contraction of muscle fibre.
25. Describe the functional unit of myofibril.
Sol. The part of myofibril between the two successive Z-lines is called sarcomere. A sarcomere comprises of a single A-band and half of each adjacent I-band.
26. Which molecule acts as an energy source for muscle contraction and how?
Sol. ATP (Adenosine triphosphate) act as energy source for muscle contraction. Myosin has an ATP binding site. ATP molecule binds to ATP binding site on myosin. Myosin acts as ATPase which hydrolyses ATP to release energy. This energy is used by myosin to bind the exposed site on actin filament to form a cross bridge. 27. (i) Name the theory which explains muscle contraction.
(ii) State the theory. Sol. (i) Sliding-filament theory.
(ii) According to this theory, the contraction of muscle fibres occurs when thin filament i.e., actin filament slides over thick filament i.e., myosin filament.
28. Explain the pivot joint formed below the elbow.
Sol. Pivot Joint: The pivot joint allows movement only in one plane. The primary movement at the pivot joint is rotation. Two bones articulate with each other where end of one bone is rounded or pointed which fits into a shallow depression of the other bone. The rounded end of the bone is fixed or stationary whereas the other bone rotates over it e.g., joint between the radius and ulna just below the elbow.
29. Explain the muscular disorder where rapid spasms occur in the muscle.
Sol. Tetany is a muscular disorder in which wild or rapid contractions occur due to hyperexcitability of the nerves. The nerves become hyper excitable due to the low level of calcium ion in the extra cellular matrix and leads to rapid spasms or rapid contractions in muscles.
30. What are the different types of arthritis? Sol. (i) Gout
(ii) Rheumatoid arthritis (iii) Osteoarthritis
Long Answer Type Questions :
31. Explain how muscles relaxe after contraction?
Sol. After the contraction of muscle, the calcium moves back into the sarcoplasmic reticulum. The amount of calcium in the sarcoplasm decreases due to which the calcium does not bind to the troponin C. The troponin undergoes change in its shape and the tropomyosin and troponin attain their earlier position and state. This blocks the active site of myosin on actin and causes relaxation of muscle.
32. Answer the following questions:
(i) Why are skeletal muscles called voluntary muscle? (ii) Why are striated muscles called skeletal muscle? (iii) Why are involuntary muscles called smooth muscles?
Sol. (i) The Skeletal muscles are called voluntary muscles because these are under the animals will or conscious, control. The animal controls the movement of such muscles.
(ii) They are attached to the skeletal component of the body and are primarily involved in the locomotory actions and changes of the body.
(iii) These muscles do not have alternate light or dark bands and give smooth appearance when observed under a microscope. The muscle fibres are not organised into parallel arrays.
33. Explain the structure of a muscle.
Sol. A whole muscle is covered by a sheath of connective tissue called epimysium. Inside the epimysium, a muscle has many muscle fibres arranged in bundles called fasciculi (singular-fasciculus or fascicle). Each fasciculus is surrounded by a sheath of connective tissue called perimysium. The muscle fibre is on surrounded by a connective tissue called endomysium. The muscle bundle are further bounded together by a common collagenous sheath of connective tissue called fascia.
34. How is action potential generated in the sarcolemma?
Sol. The contraction of the muscle is initiated by the signal sent by CNS via a motor neuron. The nerve impulse given by the CNS travels through the motor neuron. When the impulse reaches the axon terminal or neuromuscular junction, vesicles containing neurotransmitters fuses with the axon membrane. After fusion with the axon membrane they release the neurotransmitter, acetylcholine, which travels through synaptic cleft and generates action potential in the sarcolemma of the post synaptic neuron.
35. Schematically explain the breaking and forming of cross-bridges between actin and myosin filament. Sol. A B C D ATP ADP Pi
ATP binds to myosin head, causing
dissociation from actin
ATP hydrolyzed to ADP and Pi which remain
myosin association with the
head
M head attaches to actin filament
yosin Pi and ADP released;
myosin head undergoes conformational change that moves the actin and myosin filaments relative
to one another
ATP
ATP+P i
ATP P+ i
Fig. Interaction between myosin head and actin in muscle contraction. 36. How does lactic acid accumulate in the skeletal muscle? What is its fate?
Sol. The repeated contraction of the skeletal muscle anaerobically leads to the accumulation of lactic acid in the muscle. The glycogen present in the body breaks anaerobically to produce lactic acid whose accumulation causes pain and fatigue. The lactic acid accumulated in myocytes then diffuses into blood and is transported to liver. In liver 4/5th of the lactic acid is converted to glycogen by a process called glyconeogenesis and
1/5th lactic acid is oxidised to CO
2 and water.
37. What are the functions of skull? Sol. Functions of the Skull:
(i) The most important function of the skull is to protect the brain. This function is mainly carried out by the cranium.
(ii) The skull bears jaws which help the animal in cutting and masticating its food. (iii) Ear bones help in amplification of sound.
(iv) It protects and supports the special sense organs. 38. Structurally explain the backbone of the body.
Sol. The vertebral column is also known as backbone. It lies in the mid-dorsal region of the neck and trunk. It is made up of 26 serially arranged units called vertebrae. In other words the vertebral column extends from the base of the skull and constitutes the main framework of the trunk. Between the two adjacent, vertebrae, a disc or pad of fibrous cartilage is present which provides flexibility to the vertebral column. The pads or discs of cartilage present between the vertebrae are called intervertebral discs. A hollow central portion occurs in each vertebrae which together forms a structure through which the spinal cord passes.
39. Explain the three types of ribs? Sol. Ribs are of three
types-(i) True ribs: The first seven pairs of ribs are called true ribs. They are dorsally attached to the thoracic vertebrae and are ventrally connected to the sternum with help of the hyaline cartilage.
(ii) False ribs: The three pairs of ribs i.e., 8th, 9th and 10th do not directly articulate with the sternum rather
it joins the cartilage of 7th pair of ribs and hence are called false ribs because ribs generally articulate
with both thoracic vertebrae and sternum but these ribs do not articulate with the sternum directly. (iii) Floating ribs: The 11th and 12th pairs of ribs are called floating ribs because one end of the rib is attached
to the vertebral column and the other end is free. The floating ribs play an important role to protect the kidneys.
40. Describe the structural arrangement of bones or skeleton present in the forelimb of the human.
Sol. In humans, a pair of forelimbs are present. Each forelimb has 30 bones which forms the three different parts of an arm namely upper arm, lower or forearm and hand.
The single long bone of the upper arm is called humerus. The two bones present at the lower arm are ulna and radius. These two bones are either parallel or cross each other. The radius is shorter than ulna. The hand has 27 bones where 8 bones are present in wrist region, 5 bones are present in palm region and 14 bones are present in fingers. The 8 bones of the wrist are called carpals, the 5 bones of the palm are called metacarpals and the 14 bones of the fingers are called phalanges.
41. Which skeleton is situated at the lateral sides and extends outwards from the principle axis? Describe it. Sol. The appendicular skeletal system includes the skeleton of the limbs, the pectoral and pelvic girdle which
support and suspend the skeleton of limbs from the vertebral column. The girdle which supports the forelimb is called pectoral girdle and the girdle which supports the hindlimbs is called pelvic girdle. Hence, the bones of limbs, pelvic girdle and pectoral girdle constitute the appendicular skeleton. It is situated on the lateral sides which extends outwards from the principal axis.
42. (i) What is pelvic girdle? (ii) Where does it occur? (iii) What is pubic symphysis?
(iv) Name the three bones that form coxal bone. (v) What is pelvis?
Sol. (i) It is an irregular trough-shaped supporting bone. (ii) Between the hindlimbs and the axial skeleton.
(iii) The two halves of pelvic girdle meet ventrally to form a pubic symphysis. The pubic symphysis contains the fibrous cartilage.
(iv) Ilium, pubis, ischium.
43. (i) Which is the strongest, thickest and largest vertebrae present in the vertebral column? (ii) Where is it present?
(iii) How many vertebrae are present in it? (iv) What is its role?
(v) How many thoracic vertebrae are present in vertebral column? Sol. (i) Lumbar vertebrae.
(ii) In the abdomen. (iii) Five (5)
(iv) It supports the weight of the trunk. (v) Twelve (12)
44. What are the various functions of hip girdle? Sol. Functions:
(i) The two pelvic girdle joins to form a wider hollow space called pelvis. The pelvis supports and protects the abdominal visceral structures.
(ii) It is the site for the attachment of leg muscles. (iii) It is the site for the attachment of hindlimb bones. (iv) It provides strength to the sacral region.
(v) It transfers weight of whole body on the hindlimbs. 45. Describe the bones present in the leg of human beings.
Sol. Hindlimb: In humans, a pair of hindlimbs are present. Each hindlimb has 30 bones which forms thigh, shank, knee and foot.
The single longest and strongest bone present in the thigh is called femur. The two bones present in the shank region are tibia and fibula. The 7 bones of the ankle are called tarsal, the 5 bones of the sole are called metatarsals and the 14 bones that form the toes are called phalanges.
SECTION - B
Model Test Paper Very Short Answer Type Questions :
1. How many muscles are present in the human body? Sol. 639.
2. How many bones are present in the each limb of a human? Sol. Thirty (30).
3. Which is the longest and strongest bone of the body? Sol. Femur (Thigh bone).
4. Name the connective tissue that surrounds the muscle fibres present in the fasciculus. Sol. Endomysium.
5. Name the two places where we can find smooth muscles. Sol. Stomach, Lungs, Urinary bladder, Urinogenital tract (Any two) 6. Expand HMM and LMM.
Sol. HMM– Heavy meromyosin LMM– Light meromyosin 7. Define Hensen’s zone.
Sol. At the centre of the dark A-band a comparatively light band is present called H-band or Hensen’s zone. 8. Human skull is called dicondylic. Why?
Sol. There are to facets called occipital condyles on both sides of the foramen magnum and because of the presence of two condyles, in the occipital bone. The human skull is dicondylic.
Short Answer Type Questions :
9. Name and describe the cavity present in the scapula.
Sol. Glenoid cavity: Scapula has a shallow articular surface called glenoid cavity. This articulates with the head of the humerus to form the shoulder joint.
10. Name the two processes that occur in the shoulder blade. Sol. Acromion process and coracoid process.
11. What are the various functions of pectoral girdle? Sol. Functions of pectoral girdle:
(i) The pectoral girdle provides the glenoid cavity which articulates with the head of the humerus. (ii) It is also meant for attachment of the arm muscles.
This protects the delicate internal organs present in these areas. 12. What is acetabulum and where is it located?
Sol. The three bones i.e., ilium, pubis and ischium articulate or meet at a point where a cup-shaped hollow cavity acetabulum is present. The femur bone articulates with acetabulum.
13. Describe the s-shaped bone present in pectoral girdle.
Sol. Clavicle is the s-shaped, thin elongated bone which curves at two places. At one end it is connected with the acromian process of scapula and at the other end it is connected with the sternum.
14. What is foramen magnum and occipital condyle?
Sol. The base of the skull has a large opening called foramen magnum. There are two facets present on both the sides of foramen magnum. These facets are called occipital condyles.
15. Where can you find cartilages in human beings? Sol. Ear, nose, larynx etc.
Short Answer Type Questions :
16. The skeleton in man is divided into axial and appendicular. Describe the former.
Sol. The axial skeleton is the skeletal system which runs or occurs along the mid longitudinal axis of the body.
It comprises of 80 bones which distribute along the main axis and form four structures– skull, vertebral column, sternum and ribs.
17. What are cranial bones? How many are there? Why are they important in humans?
Sol. The bones of the cranium are called cranial bones. They are eight (8) in number. They protect the brain of the organism.
18. Which bones are present in the following?
(i) Hard palate (ii) Ear ossicles (iii) Hyoid apparatus. Sol. (i) Facial bone– maxillae, palatine
(ii) Incus, Stapes, Malleus. (iii) Hyoid bone.
19. Describe the ribs that protect the kidney.
Sol. Floating ribs play an important role to protect the kidneys. The 11th and 12th pair of ribs are called floating
ribs because one end of the rib is attached to the vertebral column and the other end is free. 20. Draw a diagram of sarcomere.
Sol. Fig A sarcomere Z line A band I band H zone Sarcomere
21. Name the following muscular or skeletal disease (i) A genetic disorder related with protein dystrophin (ii) Rapid spasm of muscles
(iii) Autoimmune disorder Sol. (i) Muscular dystrophy
(ii) Tetany
Long Answer Type Questions :
22. Diagrammatically explain the sliding-filament theory.
Sol. I band
A band
Z line Z line Z line
Two Sarcomeres Maximally Contracted Contracting Relaxed H zone
Fig. Sliding-filament theory of muscle contraction (movement of the thin filaments and the relative size of the I-band and H-zones)
23. Describe the different types of skeletal system in man. Sol. Types of Skeletal System: Skeletal system is of two types:
(i) Exoskeletal system: The skeleton which is external is called exoskeleton. It is a rigid, protective and supportive covering (framework) present outside the body. Exoskeleton is made up of hard structures or dead tissues present in both vertebrates and invertebrates.
(ii) Endoskeletal system: The skeletal system present inside the body of the organism is called endoskeletal system. It is the hard supporting structural framework which occurs inside the body of both vertebrates and invertebrates.
The endoskeleton in case of vertebrates is made up of bones and cartilage.
Objective Type Questions (Movements of Body Parts)
1. The movement which results in change of place or location is called
(1) Locomotion (2) Protoplasmic streaming
(3) Extensibility (4) Elasticity
Sol. Answer (1)
Locomotion : The movement that results in change of place or location.
Protoplasmic streaming : Due to movement of protoplasm, pseudopodial movements in case of organisms like Amoeba are able to move.
2. Amoeba shows movement with help of
(1) Pseudopodia (2) Flagella
(3) Cilia (4) Muscle
Sol. Answer (1)
Amoeba is unicellular organism in which movement occurs due to pseudopodia. 3. __________ circulates blood to different parts of the body.
(1) Peristaltic movement of oesophagus (2) Pumping of heart
(3) Peristaltic movement of intestine (4) Ciliary movement of oviduct Sol. Answer (2)
Pumping of heart is necessary for the circulation of blood to different parts of the body.
Peristalsis is necessary for conduction of food in alimentary canal.
Ciliary movement of oviduct conducts ovum through it.
4. The two cells of the body which show pseudopodial movements are
(1) RBCs and WBCs (2) WBCs and macrophages
(3) Liver cell and WBCs (4) Macrophages and RBCs Sol. Answer (2)
Neutrophils (WBCs) and macrophages show pseudopodial movement.
5. Which of the following structures contract and relax rhythmically to produce movement? (1) Flagella
(2) Cilia (3) Muscles (4) Pseudopodia Sol. Answer (3)
Muscles have the capibility to contract and relax rhythmically to help in movement.
(Locomotion and Muscles)
6. Which of the following is not a function of locomotion?
(1) Procurement of food (2) Finding a mate
(3) Peristaltic movements (4) Searching and building shelters Sol. Answer (3)
Locomotion helps in procurement of food, finding of mate and searching and building of shelter. Peristalsis movement in alimentary canal or oviduct helps in passage of food and ovum through them, respectively. 7. The muscle is a specialised tissue which originates from
(1) Endoderm (2) Mesoderm
(3) Ectoderm (4) Yolk sac
Sol. Answer (2)
Specialised tissue such as muscle, bones and cartilage originate from mesoderm. 8. The specialised cells that makeup the muscular tissue are
(1) Neuroblasts (2) Osteoblast
(3) Osteocytes (4) Myocytes
Sol. Answer (4)
Myocytes : muscle cells Osteoblast : bone forming cells Osteocytes : bone cells
Neuroblast : neurons forming cells
9. A human body contains how many muscles?
(1) 540 (2) 639
(3) 600 (4) 700
Sol. Answer (2)
10. A collagenous sheath of connective tissue layer holding all the muscle bundles together is
(1) Perimysium (2) Endomysium
(3) Epimysium (4) Fascia
Sol. Answer (4)
The collagenous connective tissue that holds all the muscle bundles together is known as fascia. 11. A bundle of muscle fibre is called
(1) Fascia (2) Glenoid cavity
(3) Myocyte (4) Fasciculus
Sol. Answer (4)
12. The sheath covering a single bundle of muscle fibres is
(1) Epimysium (2) Endomysium
(3) Perimysium (4) Mesoderm
Sol. Answer (3)
The sheath that covers the muscle is epimysium.
Mesoderm – germ layer
The sheath that covers a single muscle fibre is endomysium. 13. Tendons connect
(1) Muscle to bone (2) Bone to vertebral column
(3) Bone to bone (4) Bone to cartilage
Sol. Answer (1)
Tendons : Connect muscles to bones. Ligament : Connect bone to bone.
14. The plasma membrane of a muscle fibre is called
(1) Sarcoplasma (2) Sarcolemma
(3) Sarcoplasmic Reticulum (4) Syncytial Sol. Answer (2)
Sarcolemma : Plasma membrane of the muscle fibre Sarcoplasma : Cytoplasm of muscle fibre
Sarcoplasmic Reticulum : Endoplasmic reticulum of the muscle fibre. Syncytial : A cell having multiple nuclei assumed to be formed by fusion. 15. The dark band present on myofibrils is
(1) Isotropic band (2) Anisotropic band (3) I-band
(4) M-line Sol. Answer (2)
The dark band present on the muscle fibre is known as Anisotropic band which consists of myosin and actin both.
16. M-line passes through the centre of (1) Z-disc
(2) I-band (3) HMM (4) H-zone Sol. Answer (4)
M-line is the dark line made of fibrous tissue which holds the thick myofilaments together is found in H-zone.
17. The structural and functional unit of myofibril which contracts to cause movement is called (1) Sarcolemma (2) Sarcomere (3) Fascia (4) Myosin Sol. Answer (2)
The structural and functional unit of myofibril is known as sarcomere which is the section between two Z-lines. 18. A sarcomere consists of
(1) One A-band and one I-band (2) Half A-band and two half I-band (3) Half A-band and one I-band (4) One A-band and two half I-band Sol. Answer (4)
A sarcomere is the zone between two Z-lines.
Z line
A band I band
H zone Sarcomere
19. Which one of the proteins is not a part of thin myofilament? (1) Myosin
(2) Actin (3) Troponin (4) Tropomyosin Sol. Answer (1)
Thick myofilaments : myosin
Thin myofilaments : actin, tropomyosin, troponin.
(Mechanism of Muscle Contraction and Muscle Relaxation) 20. The monomeric protein which polymerises to form myosin is
(1) Actin (2) Meromyosin (3) Tropomyosin (4) Troponin Sol. Answer (2)
21. Select the correct option (1) HMM = Tail + Short arm (2) LMM = Tail + Head (3) HMM = Head + Short arm (4) LMM = Head
Sol. Answer (3)
HMM = head + short arm LMM = tail
22. ATP binding site is located on
(1) Tropomyosin (2) Actin
(3) Myosin (4) Troponin
Sol. Answer (3)
ATP binding site is located on the myosin head where ATPase is present.
23. Muscle fatigue occurs due to accumulation of (1) CO2
(2) Myosin ATPase (3) Lactic acid
(4) Creatine phosphate Sol. Answer (3)
Muscle fatigue occurs due to accumulation of lactic acid due to anaerobic oxidation of glucose. (Skeletal System, Joints and Disorders of Muscular and Skeletal System)
24. Number of floating ribs are (1) 2 pairs
(2) 12 pairs (3) 7 pairs (4) 3 pairs Sol. Answer (1)
Floating ribs : 2 pairs, 11th and 12th
A rib is said to be floating if it does not attach to the sternum or to another rib.
True ribs : First seven pair of ribs attach to the sternum (breast bone) in front are known as true ribs.
False ribs : Lower 3 pair of ribs do not directly connect to the sternum and are connected with 7th rib. 25. The number of bones present in the skeleton that run along the mid longitudinal axis of the body are.
(1) 87 (2) 90
(3) 80 (4) 78
26. Cranium protecting the brain is made up of – (1) 9 bones (2) 18 bones (3) 28 bones (4) 8 bones Sol. Answer (4) Cranium (8) — Frontal (1) Parietal (2) Temporal (2) Occipital (1) Ethmoid (1) Sphenoid (1)
27. Head of humerus articulates with _________ cavity
(1) Glenoid (2) Acetabulum
(3) Foramen magnum (4) Obturator foramen
Sol. Answer (1)
Head of the humerus articulates with the glenoid cavity present in scapula. 28. Match the following
Column-I Column-II
a. Incus (i) Hammer shaped
b. Malleus (ii) Stirrup shaped
c. Stapes (iii) Anvil shaped
(1) a(iii), b(ii), c(i) (2) a(ii), b(i), c(iii) (3) a(i), b(iii), c(ii) (4) a(iii), b(i), c(ii) Sol. Answer (4)
29. The U-shaped bone present at the base of the buccal cavity is (1) Skull
(2) Hyoid (3) Incus (4) Stapes Sol. Answer (2)
30. The longest bone of the thigh is (1) Phalanges (2) Tarsal (3) Femur (4) Metatarsal Sol. Answer (3)
The longest bone of thigh is 'Femur'. 31. Match the following
Column I Column II
a. Tarsal (i) 14
b. Phalanges (ii) 1
c. Meta tarsal (iii) 7
d. Femur (iv) 5
(1) a(iii), b(i), c(iv), d(ii) (2) a(i), b(ii), c(iii), d(iv) (3) a(ii), b(iii), c(iv), d(i) (4) a(iv), b(i), c(iii), d(ii) Sol. Answer (1)
Tarsal – 7, (talus, calcaneum navicular, cuboid, 3rd cuneiform, 2nd cuneiform 1st cuneiform)
Phalanges – 14, (3 in each finger other than toe which has 2) Meta tarsal – 5
Femur – 1
32. The joint present between radius and ulna is (1) Gliding joint
(2) Saddle joint (3) Pivot joint (4) Angular joint Sol. Answer (3)
Pivot joint : One bone rotates around another e.g., radius over ulna
Gliding joint : Two bones can glide over each other, surfaces are flat or curved e.g., wrist / tarsal bone
Saddle joint : The convex end of one bone fixes into the saddle like depression of the other bone e.g., human thumb and carpals.
Angular joint : Allows movement in two planes e.g., between metacarpals and phalanges.
33. In Myasthenia gravis ________ is affected. (1) Sarcoplasmic reticulum (2) Sarcolemma (3) Neuromuscular junction (4) T-tubules Sol. Answer (3)
In myasthenia gravis, neuromuscular junction is affected. It is an autoimmune disease in which the antibodies attack and block the acetylcholine receptors at the post synaptic membrane inhibiting the excitatory effects of neurotransmitter.
