Biology Final Exam PDF

Biology Final Exam Unit 1: Short Answers/Multiple Choice 1. X-Axis : Time 2. Y-Axis: Population Size 3. Exponential Curve: dN/dT = rN dN/dT: The change in population size over time (how fast the population is growing)...

Biology Final Exam Unit 1: Short Answers/Multiple Choice 1. X-Axis : Time 2. Y-Axis: Population Size 3. Exponential Curve: dN/dT = rN dN/dT: The change in population size over time (how fast the population is growing) If dN/dT > 0 (greater), the population is increasing ❙ If dN/dT < 0, the population is decreasing ❙ If dN/dT = 0, the population remains constant r: Intrinsic growth rate (how quickly individuals in the population reproduce) If r > 0 (greater), the population is increasing ❙ If r > 0, the population is decreasing ❙ If r = 0, the population remains constant N: Population size 4. — (Identical to #3) 5. Small-Bodied Species; because they are associated with r-values which is evident in the graph displaying instances of rapid growth in population size throughout time, driven by their high reproductive rates. 6. High Density; because small bodied species occur at high densities. More specifically, shorter life cycles and higher reproductive rates, wrestling higher population densities. 7. Density-Independent; because small-bodied species are not limited by carrying capacity given that their high reproductive rates and lower resource demands allow them to grow at a faster rate. 8. Abiotic Factors; because small-bodied species population size fluctuates depending on environmental changes. These species are regulated by carrying capacity, therefore their population would increase during favorable conditions. 9. Decrease in coyote populations results in an increase in fox populations, thus decreasing mice population. Therefore a lowered tick infection rate. 10. Decrease in acorn quantities results in an decrease in white-footed mice populations. Therefore, implicating a lowered tick infection rate. 11. Increased temperatures in summer months results in an decrease of ticks. Therefore, implicating a lowered tick infection rate. 12. Increase in deer populations results in an increase in adult ticks. Therefore, implicating a higher tick infection rate. 13. Most likely explanations for physical variation in deer are: cold environments, deer evolved larger bodies and shorter limbs to reduce surface area to volume ratio, thus minimizing heat loss. 14. Weather Event: Specific, short term event. 15. Larva stage is the least likely to transmit lyme disease because it has not yet acquired borrelia burgdorferi. 16. Main drivers of global climate have been natural occurrences: milankovitch cycles, variation in the sun’s intensity, and volcanic eruptions which influenced Earth’s climate over time. 17. Mutualistic Relationship; because the small intestine is a safe food-supply environment for bacteria, in turn, helping humans with digestion. 18. Mouse; because they are primary reservoirs for borrelia burgdorferi. 19. Least to Most Inclusive: Population, Community, Ecosystem, Biosphere. 20. Homeostasis: Maintaining stable conditions within the interval environment despite a changing external environment. 21. If a plant species has a uniform population distribution it’s presumed that secretion of chemical compounds inhibit growth of other species, to an extent. 22. Ectotherms regulate body temperatures by finding environments that enable heat loss or heat gain. 23. Adult-Ticks are important hosts for white-tailed deer. 24. Type III Survivorship Curve; because increase in lifelessness of early stage death and no parental care, implicating an r-species. 25. — 26. Acclimatization; because adaptations (raised metabolic rate and growth in thickness of fur) gradually develop over time not instantaneously. 27. Ticks are well-adapted to cold climates by becoming dormant. However, high temperatures and low humidity can exceed their survival. 28. Ectothermic (Line D); because the x and y axis of the graph represent a direct relationship given that an increase in environment temperature increases body temperature. 29. Metabolism (Line C); because the x and y axis of the graph portray that the environmental temperature remains identical as the body temperature. 30. Mutualism; because the butterfly secretes an energy source, in turn, the ants tend to the larva. 31. Body’s set point is raised during a fever, and lowers when the fever breaks. 32. In a negative feedback loop, if an individual has a sufficient number of red blood cells the body would cease production. 33. Prey cycle influences the predator cycle, vice versa. 34. Humidity is an abiotic factor that influences the density of tick populations. 35. In thermogenesis, brown fat cells have many mitochondria and produce heat. 36. Smaller organisms have a larger surface area to volume ratio therefore they can easily cool but have difficulty heating, vice versa. 37. Ecosystem: Biotic and abiotic components of an area. Unit 2: Short Answers/Multiple Choice 1. A. Draw what would be seen on an oscilloscope during an action potential. B. Label hyperpolarization. C. Resting: Open Channels: Na and K leak channels open Close Channels: Na and K channels close During AP Spike: Open Channels: Na channels open Close Channels: K channels close During Repolarization: Open Channels: K channels open Close Channels: Sodium channels close After Repolarization: Open Channels: K channels open, but gradually close Close Channels: K channels open, but gradually closing; Na channels close 2. A. Trophic Cascade (Top-Bottom): Wolve population decline resulting in an increase in moose population. Increase in wolves would result in a decline in moose population due to predation, therefore an increase in plants. B. Wolves feed on moose (-); Moose feed on fir trees (-); Wolves indirectly benefit from fir trees. C. Biotic factors that could account for the difference in moose populations include: less plant availability, presence of ticks, or brain worms. 3. Herbicide blocks the functioning of the electron transport chain when applied to a plant. Predict its effects on: H+ Gradient: Photosynthesis: No H+ gradient because the ETC cannot pump protons into the thylakoid lumen. Respiration: No H+ gradient in the mitochondria since the ETC is blocked. Production of NADPH: No NADPH because Photosynthesis: No NADPH produced as electrons cannot flow to NADP+. Respiration: Buildup of NADH given that it cannot donate electrons to the ETC. Production of ATP: Photosynthesis and Respiration: ATP production would be reduced because the lack of proton gradients prevents ATP synthase from functioning. Production of Glucose: No glucose produced because ATP and NADPH are required in photosynthesis. 4. Structural Plant Defense: Spines or thorns which are non-digestible thus limiting herbivory. Chemical Plant Defense: Producing bad tasting or toxic compounds thus limiting herbivory. 5. Observations: Drug did not affect any of the presynaptic steps; Drug caused increased depolarization in the postsynaptic. Hypothesis: Drug increased number of postsynaptic receptors. 6. Number of Foxes = Energy Required per Fox / Total Energy Available → Number of Foxes = 100 / 25 = 4 7. The overall outcome of the light-dependent reaction is that: NADPH and ATP are produced during the light reactions and are used to power the light-independent reactions. 8. Less reproduction and increased mortality rate in populations that must resort to less nutritious food. 9. Plant adaptations to prevent herbivory include: having spines or thorns, producing bad-tasting chemicals, producing sweet tasting food to lure in predators of herbivores, and growing on the edge of cliffs. 10. Parts of a chloroplast include an outer membrane, stroma, grandum, thylakoid, and inner membrane. 11. Hawk; because energy is lost at each level therefore the highest level supports the smallest biomass. 12. Ion Concentration at Rest: Sodium, high concentration outside the cell and low inside. Potassium high concentration inside the cell and low outside. 13. Chemoreception in smell and taste and neutron transmission at synapses are similar because they involve a neurotransmitter creating an action potential in sensory cells and a chemical attaching to a chemically-gated ion channel. 14. Heat wave is an abiotic factor that influences the moose population on Isle Royale. 15. The stomata of a plant closing, results in: a drop in CO₂ entering, a decrease in primary productivity, conservation of water, and a drop in light-independent reactions of photosynthesis. 16. Interchangeable sequential flow of information in the stretch receptor associated with the knee-jerk reflex includes: stimulus, neurotransmitter release, action potential, ion channels, receptors. 17. Acetylcholine (ACh) is a neurotransmitter released by motor neurons, which is broken down in the synaptic cleft by acetylcholinesterase (AChE) resulting in a decrease in heart rate. The process of ACh release: Stimulus (e.g. touch/movement): Activates sensory receptors, which generates an electrical signal that travels to the nervous system. Depolarization: The stimulus cases Na channels to open and flow followed by the opening of ion channels. Allowing sodium ions to flow o nitiates an action potential in the nervous system, which travels 18. Stereocilia, tiny-hair structures on the surface of hair cells, bend in response to sound waves. When stereocilia bend, mechanically-gated ion channels open thus allowing potassium ions to flow into the hair cells, leading to depolarization and the generation of a signal. 19. Cochlear implants bypass damaged parts of the cochlea and stimulate the auditory nerves with electrical signals. However, if the auditory nerve is abnormal or damaged, the cochlear implant cannot send signals to the brain. 20. Senses that rely on mechanical sensations like hearing are those that detect physical forces, such as pressure, vibration, movement, or sound waves. 21. Although all sensory systems transduce reception of a stimulus into action potentials, different stimuli are perceived as different sensations because each sensory system has specialized receptors that respond to a particular type of stimulus. Examples include: photoreceptors for light (vision), mechanoreceptors for pressure/vibration (touch and hearing), and chemoreceptors for chemicals (taste and smell). The brain interprets action potentials based on where they came from and where they are processed in the brain. 22. Adaptation is a heritable structural, behavioral or physiological trait that increases the survival and fitness of an individual. 23. During and immediately after an action potential, the area of the neuron is in a refractory period. During this period, the sodium channels are closed and inactive, even if a depolarizing stimulus occurs because the channels require time to reset to their closed state. Therefore, the area of a neuron can’t merely upstream of a currently occurring actional potential depolarize. 24. Sensory perceptions of animals include: Reception: Detecting a stimulus Transduction: Converting the stimulus into electrical signals Perception: Interpreting the signal 25. Trophic Levels; Secondary/Tertiary Consumers. 26. Trophic Cascade Hypothesis; implicates that the loss of gray wolves would impact the lowered trophic levels. 27. Chemically-Gated Channels open when a neurotransmitter like acetylcholine (ACh) binds to a receptor of a postsynaptic membrane. 28. Wolves prefer to live in larger packs although less food because they lose less food to scavengers. 29. Photoautotrophs are organisms that use light energy to produce food through photosynthesis including all plants, algae, and cyanobacteria. Some prokaryotes are chemoautotrophs (uses chemical energy) or heterotrophs and most eukaryotes are heterotrophs. 30. Most to least inclusive: Leaf, Mesophyll, Chloroplast, GRanum, Thylakoid, Chlorophyll, Thylakoid Lumen. Unit 3: Short Answers/Multiple Choice 1. A. Prokaryotes: Simple, single-celled organisms that lack a nucleus and membrane-bound organelles (no mitochondria, chloroplasts, golgi bodies) e.g. bacteria and archaea. B. Derived characteristics of prokaryotes: No nucleus and no membrane-bound organelles. C. Monophyletic Group is a group of organisms that include a single common ancestor and all its descendants. D. Eukaryotes: Complex celled organisms that contain a nucleus and membrane-bound organelles (mitochondria, chloroplasts, golgi bodies) e.g. plants, animals, fungi. E. Derived characteristics of eukaryotes: Nucleus and membrane-bound organelles. F. Monophyletic Group is a group of organisms that include a single common ancestor and all its descendants. 2. A. Consider Ficks Law: Q = DA (P1 - P2) / L Q: Rate of diffusion A: Diffusion coefficient *Higher D allows faster diffusion A: Surface area available for diffusion *Larger surface area increases Q because there's more spaces for molecules to move. P1 - P2: Difference in partial pressure from origin to target. L: Distance over which gas diffuses from P1 to P2. B. Emphysema: Walls of alveoli break down and are scared so that many alveoli merge to become larger air spaces. A: Decrease; One large sphere has lower surface area than many smaller spheres; Fewer walls means less area for oxygen to enter the blood and carbon dioxide to leave. P1 - P2: L: Acute Pneumonia: Accumulation of fluid inside the alveoli from vascular leaks and inflammation. A: P1 - P2: L: Supplemental Oxygen: A patient is placed on 100% oxygen through nasal cannula (instead of “normal” air, which is 21% oxygen). A: P1 - P2: L: 3. Biological Species Concept states that a group of interbreeding organisms are reproductively isolated and produce fertile offspring. This example is applicable to the concept because the female species of frogs are selective on the type of male species to reproduce dependent on their music. 4. A. Evolution is just a theory. A theory is a tested and verified explanation, therefore evolution is not merely a theory because it is supported by a body of evidence. B. Only the most fit survive (survival of the fittest). Survival of the fittest is not merely depdenet on reproductive and adaptable traits. Generally, organisms with mutations are classified as “least fit;” not having the most ideal anatomical or morphological structures. However they are still capable of living a typical lifespan. 5. A derived characteristic of homo sapiens is bipedalism, a fully opposable thumb that can touch the little finger. 6. Primary use of phylogenetics include: identifying pathogens, tracing food contamination, and genetic components of diseases. 7. With a large number of infected hosts, the virus has ample opportunities to replicate, mutate, and evolve rapidly to adapt to humans as its primary host. 8. Path of oxygen through inhaling until used in biceps to fuel a contraction is trachea, bronchus, bronchioles, alveolus, alveolar epithelium, tissue fluid, capillary endothelium, plasma, red blood cell ,membrane, and hemoglobin. 9. Microevolution; because body size changes between northern and southern sparrows of the same species is a minor evolutionary change. 10. When an antibiotic is applied to a population of bacteria, an allele for resistance already present in the population increases in frequency. In any bacterial population, some individuals already have an allele that is resistant before the antibiotic is introduced. 11. Natural Selection: Organisms with favorable traits are more likely to survive and reproduce. This process can only occur when genetic variation already exists, descent with modification, and differential reproductive success. 12. Evolution explains how populations change over generations. Some mechanisms are due to random chance or difference in survival and reproduction of individuals with adaptations. 13. A new mutation in a population is a random event that can be either beneficial, neutral, or harmful. 14. Pathogens are typically more virulent in new hosts because they had not yet had a chance to evolve resistance to the pathogen. 15. A mechanism of evolution associated with random changes in allele frequencies is genetic drift. 16. Evolution is a scientific theory supported by ample evidence, which can occur over short or long time periods. Populations can evolve and adapt to changing environmental conditions. “Survival of the Fittest” is an oversimplified phase, which in biological terms refers to reproductive success. 17. Myxoma virus was initially virulent, which resulted in a rapid decline in the population. However, the virus host was gradually disappearing, and only the less virulent virus variants survived. Therefore the rabbit population began to evolve resistance. 18. The longer leg trait is a tradeoff and suggests genetic variation (different alleles) within the population. However, organisms as “more highly evolved” is misleading and untrue. 19. Gene Flow because both types of organisms from the mainland swim to the island. Followed by natural selection because light-colored snakes are more common because they likely have a selective advantage. 20. New alleles are created by mutations. Natural selection, gene flow, and genetic drift act on existing variation; they do not create new alleles. 21. Genetic drift because the mountain lions became randomly isolated in a new habitat. Followed by the founder effect because the small group of species became isolated from a larger population and started a new population. 22. Genes are different forms of the same alleles. Not to mention, there is extensive study on genes, however minimal study on alleles. 23. If a population is not evolving: the population must be very large, no migration into or out of the population, population, different genotypes must not confer to different levels of fitness, and applicable to Hardy Weinberg Equilibrium. 24. Doubt reduced seed availability, and only birds with larger beaks could crack the available seeds. 25. Evolution because there is a change in allele frequencies over time and Natural selection because their larger beak size can be deemed as favorable for survival. 26. Lyme Disease is caused by a bacterium which is a prokaryotic organism. Bacteria are larger than viruses and can be killed with antibiotics, which specifically target bacterial structures.