KEY to EOC REVIEW PACKET
Remember;; relax! Everything and everyone will be ok! Have
confidence in yourself. Study over the weekend but do not stress too much. Take deep breaths whenever you get overwhelmed and just ShAkE iT oFf!! Do not forget to use the other tools on Mrs.
Renn’s website! :) https://www.youtube.com/watch?v=nfWlot6h_JM
EOC Biology Test Review- Overview of Introductory Biology
Cell Basics and Homeostasis
1. What is the difference between a prokaryotic and a eukaryotic cell? Give an example of each type of cell.
A prokaryotic cell does not have a nucleus or membrane bound organelles and would be bacteria. A eukaryotic cell has a nucleus and membrane bound organelles and would be plant, animal, protist, or fungus.
2. What are the three parts of the cell theory?
All cells come from pre-existing cells, all living organisms are made up of cells, and cells are the basic building block of life.
3. What contributions did these scientists make to the study of cells: Schwann, Schleiden, Virchow, and Leeuwenhoek?
Schwann, Schleiden and Virchow helped to create the cell theory. Schwann found that all animals were made of cells;; Schleiden found that all plants were made of cells (so combined their theory reads that all living organisms are made of cells). Virchow found that all cells come from pre-existing cells. Leeuwenhoek made the first microscope.
4. Define homeostasis. Give an example of an organism attempting to maintain homeostasis.
Homeostasis is maintaining equilibrium/balance internally. An example would be sweating to maintain normal internal temperature.
The Cell and Organelles
5. Use a chart to illustrate and describe the structure and function of the following organelles: nucleus, nucleolus, mitochondria, chloroplast, lysosome, vacuoles, vesicles, ribosomes, endoplasmic reticulum, Golgi apparatus, cilia, flagella, chromosome, cell membrane, nuclear envelope, cell wall and cytoplasm. (Please do not copy and paste illustrations.)
Nucleus-brain/control center of the cell, holds DNA Nucleolus- makes ribosomes (aka rRNA)
Mitochondria- powerhouse of the cell, converts energy into ATP Chloroplast- place of photosynthesis
Lysosome- think Lysol! Kills bacteria, recycles old cell parts, and breaks down organic molecules Vacuoles- storage containers
Vesicles- shipping containers (like a box) Ribosomes- make proteins
Endoplasmic reticulum- rough ER~ holds ribosomes;; smooth ER~ makes lipids
Golgi apparatus- think UPS! Takes in vesicles of proteins, sorts them and ships them to where they need to go
Cilia-hair like projections that help in movement and feeding in some cells Flagella-whip-like tail helps in movement
Chromosome-made of DNA
Cell membrane-made of a phospholipid bilayer, controls what enters and leaves the cell (called a semi-permeable membrane)
Nuclear envelope- membrane surrounding the nucleus Cell wall-give structure to plant and bacteria cells Cytoplasm- gel-like fluid within the cell
6. Identify 3 main differences between an animal and plant cell.
Plants have chloroplast, and cell walls, whereas animals do not. Plant cells are more rectangular in shape, where animal cells are more rounded. Plants also have a water holding vacuole (central vacuole).
7. Why is there a limit to the cell size?
If a cell gets too big, the necessary nutrients cannot enter the cell through diffusion quick enough to meet the demands of the chemical reactions in the cell. This is because the surface area to volume ratio decreases as size increases (bigger cells actually have less surface area in relation to cubic area of cytoplasm than small cells). Big cells can solve this problem by being long and thin.
Photosynthesis and Cellular Respiration
8. Write the overall equation for photosynthesis. Identify the products (at the end of the equation) and the reactants (at beginning of equation).
6CO2 + 6H2O + light -> C6H12O6 + 6O2
9. Where is chlorophyll found in a plant cell?
Within the chloroplast (it is the actual green pigment) 10. What role does chlorophyll play in photosynthesis?
It actually captures the sunlight to jumpstart photosynthesis
11. Write the overall equation for cellular respiration. Identify the products (at the end of the equation) and the reactants (at beginning of equation).
C6H12O6 + 6O2 -> 6CO2 + 6H2O
12. Use your knowledge of the carbon/ oxygen cycle to explain the relationship between photosynthesis and respiration.
Photosynthesis makes glucose which is used in cellular respiration to make ATP. It is then turned back into carbon dioxide which is used in photosynthesis. Water is broken down to form oxygen during
photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water.
13. How is breathing and cellular respiration the same? Different?
Breathing actually brings in oxygen into the lungs to be diffused through the cells. The oxygen is then diffused into the cells and into the mitochondria in order to participate in the process of converting the bonds of glucose molecules into ATP.
Energy
14. Define the term energy.
The ability to do work.
15. When chemical bonds are formed between two atoms, is energy being released or stored?
Forming bonds releases energy.
16. What are the three parts of an ATP molecule?
Adenine, Phosphate group (three phosphates), and a sugar (ribose)
17. Which bonds in an ATP molecule are identified as “high energy bonds”? What happens when these bonds are broken? Formed?
The high energy bonds are between the phosphorous molecules. When the bonds are broken, energy is taken in, when they are formed energy is released allowing enough energy to perform the necessary action/reaction.
19. Show how ADP and ATP can be recycled as energy is stored and released.
ATP contains stored energy. A convenient way to remember the cycle is ATP = ADP + P + Energy.
20. State the first and second laws of thermodynamics and gives examples of each.
1st: energy cannot be created or destroyed...it can only change form. EX: pushing a car uphill takes energy from you, but when you get to the top of the hill the car now has more energy than you do (it can now move down the hill without you pushing it)
2nd: entropy (disorder) always increases. EX: ice -> water -> steam
21. How does the first law of thermodynamics relate to photosynthesis and cellular respiration?
All of the atoms are on both sides of the equation (reactants and products) they just change into new combinations.
Cell Division
23. List and explain the steps of the cell cycle. (IPMATC) Interphase-G1-cell grows, S-DNA is copied, G2- prep for PMATC
24. At what point is DNA replicated in the cell cycle? Why is DNA replication necessary in the cell cycle?
DNA is replicated in the synthesis phase (S phase). This is necessary so that we have extra chromosomes to give to the new cell we are going to make. (When you’re pregnant you eat for two people)
25. List and explain the phases of mitosis. (PMATC)
Prophase-chromosomes form, centrioles appear, the nuclear envelope disappears;; Metaphase-
chromosomes move to the middle of the cell;; Anaphase- (ana means back) sister chromatids pull pack to the sides of the cell;; Telophase- (opposite of prophase) chromosomes relax, centrioles disappear, nuclear envelope reappears;; Cytokinesis- cell membrane and cytoplasm split into two cells. This is technically not part of mitosis but often happens at the same time as telophase.
26. What type of cell undergoes mitosis? What type of cell comes out of mitotic division?
Mitosis forms body cells (somatic cells) during growth of a multicellular organism that are identical in the number of chromosomes to the parent cell. Some single-celled organisms use mitosis to reproduce asexually.
27. Use a chart to show the differences in mitosis and meiosis. (Include: # of daughter cells, Haploid/diploid, difference in phases)
Mitosis Meiosis (go through PMAT twice)
Interphase G1, S, G2 G1 and G2
Prophase Chromosomes form, centrioles
appear, nuclear envelope disappears
Chromosomes form, homologous chromosomes pair up, centrioles appear, nuclear envelope disappears
Metaphase Chromosome move to the middle
of the cell
Homologous chromosome pairs move to the middle of the cell
Anaphase Sister chromatids move back
toward sides of cell
individual chromosomes move back toward sides of cell
Telophase Opposite of interphase Opposite of interphase
Cytokinesis Cell membrane and cytoplasm
split in half
Cell membrane and cytoplasm split in half
Number of Daughter cells 2 4
Haploid/Diploid daughters Diploid Haploid
28. Create an operational definition for the term cancer as it relates to mitosis and cell division.
Cancer is when the cell goes out of the cell cycle. It goes through the cycle so fast without checking to make sure that it is made correctly and there are so many cells that wind up being made. (You’re driving a car and you have no brakes so you cannot stop or you have constant green lights so you don’t need to stop)
Nucleic Acids and Protein Synthesis
29. What is the difference between a purine and a pyrimidine?
Angels and Gods are pure (Adenine and Guanine), leaving C and T (Cytosine and Thymine) as pyrimidines Angels and Gods are so pure they have two rings (in their structure) and C and T only have one ring 30. List and explain the steps of DNA replication
Helicase unwinds the two strands of DNA creating a replication fork, then DNA polymerase attaches to one strand to add on new nucleotides (A pairs with T, C pairs with G), one strand is added correctly and the other is added in segments (the segmented strand is the lagging strand, the correct strand is the leading strand), once all of the nucleotides have been added on the DNA polymerase falls off and the two new strands coil up again
31. Explain the relationship between DNA and chromosomes.
Chromosomes are coiled up DNA and associated proteins called histones.
32. State the three main differences between RNA and DNA.
RNA-ribose sugar, uracil instead of thymine, and is single stranded;; DNA- deoxyribose sugar, thymine and is double stranded
33. What are the steps involved in the synthesis of a protein?
Copy of one side of the DNA strand (called mRNA or messengerRNA), mRNA moves to cytoplasm then to the ribosome, mRNA goes through the ribosome 3 nucleotides at a time (called a codon), tRNA
(transferRNA) which holds the opposite three nucleotides (called an anti-codon) matches up with the codon, tRNA releases the amino acid on top of the anti-codon and they attach together to make the protein based on the code of the mRNA
http://www.youtube.com/watch?v=41_Ne5mS2ls
34. What is DNA fingerprinting? Name some uses of DNA fingerprinting.
DNA fingerprinting shows the length of certain strands of DNA. Can be used in criminal investigations or to establish paternity
35. Define the Human Genome Project. Does the HGP threaten our civil liberties? Please support your answer.
Long-term research effort to identify the estimated 30,000 genes in human DNA and to figure out the sequences of the chemical bases that make up human DNA. This can become a threat because now we can create designer babies along with other projects that allow us to become God-like.
Genetics
36. State the laws of segregation and independent assortment.
An analysis of genetic crosses depends upon an understanding of Mendel's two laws:
• The principle of segregation (First Law): The two members of a gene pair (alleles) on homologous chromosomes segregate (separate) from each other in the formation of gametes. Half the gametes carry one allele, and the other half carry the other allele.
• The principle of independent assortment (Second Law): Genes for different traits assort independently of one another in the formation of gametes. (except in the case of linkage)
37. What is gene linkage? How does gene linkage explain the observation that most people with red hair also have freckles?
Genetic linkage is the tendency of alleles that are located close together on a chromosome to be inherited together during meiosis. Genes whose loci are nearer to each other are less likely to be separated onto different chromatids during chromosomal crossover, and are therefore said to be genetically linked. Red hair and freckles are linked alleles.
38. What is a mutation? What is the difference between a chromosomal mutation and a gene mutation?
Give an example of each and tell what effects each may have.
A mutation is a permanent change of the nucleotide sequence of the genome of an organism, virus, or extrachromosomal DNA or other genetic elements. It occurs randomly due to copying errors during replication, mistakes during mitosis or meiosis, or damage from heat, chemicals or UV light.
A chromosomal mutation may be due to an error in mitosis or meiosis.
Chromosome mutations can result in changes in the number of chromosomes in a cell or changes in the structure of a chromosome. Unlike a gene mutation which alters a single gene or larger segment ofDNA on a chromosome, chromosome mutations change and impact the entire chromosome.
39. How is the effect of a sex cell mutation different than that of a somatic cell mutation?
A sex cell mutation can be passed on to offspring or is able to be inherited. All the cells in the offspring will have that mutation so it has a relatively large effect compared to a somatic cell mutation. A somatic cell mutation is not inherited by offspring.
40. What is genetic variability? Explain the relationship between the following factors and genetic variability: sexual reproduction and mutation.
Genetic variability it is a measure of the tendency of individual genotypes (sequence of A, T, C, and G) in a population to vary from one another. This variabiity in genotypes provides a diversity of traits or phenotypes in the population.
Ecology
41. Write a one-page story (12 pt font, double-spaced) about a carbon atom as it moves between the biotic and abiotic parts of its cycle. Be creative and descriptive! Be sure to explain the roles of photosynthesis and cellular respiration in the carbon cycle.
A huge abiotic source of carbon in the air (and water) in the form of CO2 (carbon dioxide). CO2 is taken into the biotic part of the ecosystem through photosynthesis, whereby plants and photosynthetic microorganisms fix carbon into sugars/carbohydrates. Photosynthesis also gives off O2 into the air. The plant uses these carbohydrates to make other molecules such as proteins nucleic acids and lipids. Animals eat plants or other photosynthetic organisms. They all use carbohydrates in a process called cell respiration to produce energy/ATP. Just think, some of the carbon atoms inside you were once part of a dinosaur!
42. What is global warming?
Global warming (aka climate change) is the term used to describe a gradual increase in the average temperature of the Earth's atmosphere and its oceans, a change that is believed to be permanently changing the Earth's climate.
Human’s burning of fossil fuels since the industrial revolution has caused a rapid increase in CO2 levels which causes a greenhouse effect whereby the sun’s energy is trapped as heat in the atmosphere and increases global average temperatures. The result is higher average global temperature and severe changes in weather patterns each year which disrupts ecosystems. Furthermore, the North and South Poles are where the greatest increase in temperature is occurring and is causing the polar ice caps to melt
resulting in sea level rise. The distribution of the earth’s biomes will shift with changes in temperature and precipitation. Many species are expected to go extinct because the climate is changing too quickly for them to adapt evolutionarily.
43. Describe what occurs in the water cycle (including evaporation, transpiration, condensation and precipitation). What is the role of plants in the water cycle?
evaporation - movement of water from a liquid on the surface to a gaseous state in the air.
transpiration - the movement of water from the stomates into the air.
condensation - the formation of liquid water from its gaseous form.
precipitation - movement of water from the air to the surface in the form of rain, sleet, and snow.
Plants take in water from the soil through their roots and move it to the air through transpiration. This has a huge effect on levels of precipitation.
44. Using a food chain as an example, describe how the sun is the ultimate source of energy on earth.
In the process of photosynthesis, photoautotrophs/producers use sunlight energy to fix carbon and build sugars and subsequently other biological molecules or plant biomass. The biomass of the producers is used by primary consumers/herbivores to build their own biomass. In turn, secondary and tertiary consumers eventually obtain the energy from down on the food chain.
45. What is a trophic level? Which trophic level always contains the largest number of organisms? Why is this necessary?
The trophic level of an organism is the position it occupies in a food chain (autotroph vs. heterotroph). The word trophic derives from the Greek τροφή (trophē) referring to food or feeding.
The lowest trophic level or producers contain the largest number of organisms or biomass. Energy is lost as heat at each level as one moves from producers to tertiary consumers and only 10% of the energy is available to the next trophic level. The energy pyramid needs to have a wide base in order to provide enough energy for the higher levels to persist. There are typically no more than 4 or 5 trophic levels in an energy pyramid.
ENERGY PYRAMID
46. Why is the transfer of energy within a food chain not 100%?
Energy is lost as heat at each level as one moves from producers to tertiary consumers and only 10% of the energy is available as stored energy in biomass to be consumed by the next trophic level.
47. What is biomagnification? Explain the effects of DDT on each of the 3 levels of the food chain (producer, primary consumer, secondary consumer)?
Biomagnification - an increasing concentration of stored contaminants such as heavy metals in the tissue of organisms as one moves up the food chain.
DDT is an insecticide banned in the U.S. because of its effects on wildlife. It nearly caused the extinction of the bald eagle and other raptors. Bald eagles mainly consumed fish that were primary or secondary consumers. The fish had low concentrations of DDT in their tissue but because bald eagles eat many fish
and stored all the DDT, they had a much higher concentration - biomagnification. It caused them to produce eggs with very thin shells that would break under the weight of the parent in the nest. Nearly all the young died. After DDT was banned, the bald eagle and other raptors began a rapid recovery.
48. How is the energy that runs through a food chain the direct result of the carbon cycle?
The carbon cycle is coupled with energy flow into and out of the biotic portion of an ecosystem. Carbon is the backbone of the energy molecules or carbohydrates produced in photosynthesis. When carbohydrates are broken down for energy in cell respiration, carbon dioxide is released back to the abiotic part of the ecosystem, the air.
49. Define the term symbiosis. What is the difference between mutualism, commensalism and parasitism?
Symbiosis - A close interaction between two species living in close physical association with one another.
Mutualism - both species benefit from each other (pollinators and flowering plants)
Commensalism - one species benefits and the other has neither a positive or negative gain.
Parasitism - one species benefits (parasite) and the other species is negatively affected (host)
50. Under what conditions will competition exist between organisms?
Where there is an overlap in their resource use or niches (e.g., diet, nest sites, territories, cover habitat, etc.) they will compete.
51. What is a niche? Can two organisms occupy the same niche? Why or why not?
The function or position of a species within an ecological community. A species's nicheincludes the physical environment to which it has become adapted as well as its role as producer and consumer of food resources.
52. Explain how each of the following abiotic factors affects the balance of an ecosystem: water, sunlight, salinity, pH, soil type, temperature.
Water - organisms are adapted to certain levels of water/moisture levels in their environment. An imbalance (either too much or too little) will result in changes in populations of organisms because some will live and others will die.
Sunlight - availability of light is important in driving photosynthesis and thus the entire food chain relies on it.
However, sunlight also affects temperature and moisture. Plants and other photosynthetic organisms have varying physical and behavioral adaptations to getting adequate sunlight. Ectotherms utilize sun to warm their bodies through basking behavior.
Salinity - The concentration of salt both in aquatic ecosystems affects the movement of water into and out of the cells of organisms living in that environment. Organisms have adaptations to maintain water balance depending on whether they live in a hyper-, hypo- or isotonic environment. In some ecosystems salts are a limiting nutrient.
53. Explain the difference between density dependent and density independent limiting factors. Give an example of each.
Density dependent factors are factors that affect the population growth rate that DEPEND on the size of the population. For example, availability of prey decreases as population size goes up because prey are being eaten.
Density independent factors are factors affecting population growth rate that DO NOT DEPEND on how big the population is. For example, weather will affect affect everyone in the population regardless of how big the population is.
54. In general are density dependent and density independent limiting factors biotic or abiotic factors?
Density Dependent factors are generally biotic whereas density independent factors are abiotic.
55. Explain the process of succession and distinguish between primary and secondary succession.
Ecological succession is the observed process of change in the species structure of an ecological community over time usually do to interactions between species. Primary succession starts from bare mineral rock or soil without any seeds present for example after a huge glacier recedes. Secondary succession happens after an event such as a fire kills most of the vegetation but leaves seeds in the soil.
56. Define carrying capacity. Explain how it can act as a limiting factor to population growth.
The carrying capacity of a biological species in an environment is the maximum population size of the species that the environment can sustain indefinitely, given the food, habitat, water, and other necessities available in the environment. In the graph, it is where the population levels off because resources are limited. It is due to density dependent factors.
57. Briefly define each of the following human-caused changes in the environment and describe the effects on organisms and ecosystems.
a. Habitat Fragmentation - loss of habitat such as forests due to clearcutting and development leaves behind smaller fragments of the original habitat that are often disconnected from one another. Extinction of many species is associated with habitat loss and fragmentation.
b. Invasive/Exotic Plants - any species that is moved from one part of the world (exotic) and introduced into a new area where it then invades ecosystems and outcompetes native flora and fauna. The native species in the ecosystem are often negatively affected by invasive/exotic species because they did not coevolve with it so they are weak at competing or they are not able to escape or defend themselves (if the invasive species is a predator or a disease).
c. Acid Rain - is a rain or any other form of precipitation that is unusually acidic, meaning that it possesses elevated levels of hydrogen ions (low pH) mostly due to emissions from burning fossil fuels. It can have harmful effects on plants, aquatic animals and infrastructure.
d. Damage to the Ozone Layer - The ozone layer refers to a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet (UV) radiation. It contains high concentrations of ozone (O3). Depletion of ozone around the North and South Poles is largely due to human emissions of CFC’s (refrigerants) and nitrous oxides with react with ozone and break it down. This has resulted in an increase in UV light reaching the earth’s surface.
e. Antibiotic Resistant Bacteria - large-scale industrial use of antibiotics in raising livestock has resulted in the rapid evolution of bacteria that have genes that make them resistant to antibiotics. This occurs because when a bacterial population is exposed to antibiotics, only the individual cells not resistant to antibiotics are killed but the ones that have a mutated gene for resistance will survive and reproduce.
Eventually most of the population is resistant.
Evolution
58. Explain why natural selection is the process responsible for evolution.
Natural selection is the process whereby the frequency of alleles (or traits) in a population change because some traits allow individuals in a population to survive and reproduce better than others. Traits that increase fitness are called adaptations. Natural selection is a major force of evolutionary change but it is not the only one. Anything that changes allele frequency, including mutations and genetic drift, are also responsible for evolutionary change.
59. What can the analysis of DNA and amino acid sequences tell us about the evolutionary relationship between two organisms?
DNA is made up of nucleotides (A, C. T. G) in a sequence that codes for the amino acids of a protein.
Random changes in the code are called mutations and they occur regularly due to mistakes in copying DNA or exposure to chemicals or UV light. By counting the number of mutations in a gene for a protein that is
shared by many species (e.g., hemoglobin), one can tell how long ago the speciess diverged from their common ancestor.
60. What is the difference between directional, stabilizing and disruptive natural selection?
Stabilizing selection results in population with a higher frequency of alleles (a trait) closer to the mean.
Directional selection results in a shift in the mean toward one extreme of the curve possibly because one trait at an extreme results in very high mortality.
Disruptive selection results in a population in which the mean is selected against and both extremes are favored under some circumstances resulting in a split between the two traits.
61. Explain why traits that do not confer an advantage may disappear over time.
Traits that do not confer an advantage but instead cause individuals with that trait to have lower survival and lower reproductive success does not get passed on to the next generation and eventually may disappear from the population.
62. Who is the author of The Origin of Species? What famous theory was introduced in this book?
Charles Darwin published The Origin of Species on November 24, 1859. The book radically changed our understanding of the natural world because it introduced the idea that all species descend from a common ancestor on a tree of life and natural selection over long periods of time gave rise to the incredible diversity of life on earth. This is the theory of evolution by natural selection. Russell Wallace also came up with the same theory independently. The Origin of Species challenged the widely held idea at the time that a god created all things on Earth.
63. Compare and contrast analogous, homologous, and vestigial features. What can these features tell us about the evolutionary relationship between two organisms?
Analogous structures - different origin/ different underlying structure but same function (e.g., wings of a bat and wings of a butterfly are used to fly but they are not similar in their structure)
Homologous structures - same origin/ underlying structure but often different function (e.g., legs of a deer are used for walking and flippers of a whale are used for swimming but they contain similar bones that have changed in size as they became adapted to their different functions).
Vestigial structures - structures that are left over from an earlier ancestor but are no longer useful in their current form.
64. What can the examination of the embryos of two organisms tell us about their evolutionary relationship?
Early in development, closely related organisms are very similar to one another as they contain similar genes that control underlying structural forms and body plans. For example, early embryos of fish, reptiles, amphibians, birds, and mammals look nearly identical because they are closely related.
Classification and the Kingdoms of Life
65. Name the 3 Domains and the six kingdoms used for classification of living things and provide an example of an organism from each kingdom.
3 Domains: Eubacteria, Archaebacteia, and Eukaryota
6 Kingdoms: Eubacteria, Archaebacteria, Protista, Fungi, Plants and Animals
66. Create a semantic chart that categorizes each kingdom as: prokaryotic or eukaryotic, multicellular or unicellular, heterotrophic or autotrophic.
SIX KINGDOMS CHARACTERISTICS CHART
Eubacteria Archaebact
eria
Protista Fungus Plant Animal
Cell Type prokaryotic prokaryotic eukaryotic eukaryotic eukaryotic eukaryotic
Number of Cells
unicellular unicellular most unicellular
most multicellular
multicellular multicellular
Mode of Nutrition
auto/heterotr oph
auto/heterotr oph
auto/heterotro ph
heterotroph (absorption
)
autotroph heterotroph
Examples Escherichia coli Streptococcu
s
methanobact eria
algae, diatoms, amoebas,
lichen, yeast, mushrooms
trees flowers
grass
sponges
mammals
67. What evidence led scientists to classify archaebacteria in a kingdom separate from eubacteria? based on DNA evidence that they were very different
68. What is a phylogenetic tree? Draw a phylogenetic tree showing the evolutionary relationship between the 6 kingdoms.
69. How is a virus different from a cell? Is a virus an organism? Why or why not?