AP BIO FINAL

Based on the information presented, which of the following is the most likely explanation for a buildup of cholesterol molecules in the blood of an animal?

The animal's body cells are defective in endocytosis.

The maximum production rate of acetyl-CoA under condition 1 is closest to which of the following?

a. 1 micromole/sec

Which of the following observations provides the best evidence that acetyl-CoA negatively regulates pyruvate dehydrogenase activity?

The rate of the pyruvate dehydrogenase-catalyzed reaction is slower in the presence of a higher concentration of acetyl-CoA.

The diagram below shows energy changes in a specific chemical reaction with and without the addition of an enzyme to the reaction.

Which of the following questions can best be answered by the diagram?

Does the addition of an enzyme reduce the activation energy required for a reaction?

A researcher claims that different metabolic pathways allow bacteria to use different molecules as sources of matter and energy.

Which of the following statements best helps justify the researcher's claim by providing a relevant example?

E. coli bacteria reproduce in liquid media containing either glucose or galactose.

Scientists compared the chemical structure of several molecules that various bacterial species use for quorum sensing. Quorum sensing is an ability some bacteria have to detect the number of related cells nearby. The chemical structure of some of these molecules found in certain species of bacteria are shown in Figure 1. Figure 1. The chemical structure of several molecules used for quorum sensing in three species of bacteria .

Which of the following research questions would best guide an investigation of the link between the structure of the signaling molecules and the evolution of quorum sensing?

Did these species evolve from a common ancestor that used a similar signaling molecule?

Which of the following describe the processes by which the bacteria are breaking down glucose to produce lactic acid?

The bacteria are breaking down sugars in the absence of oxygen.

which of the following was the dependent variable in the researchers experiment?

pH

Which of the following graphs best represents the data in Table 1 ?

..

Which one of the following cells is likely to be the most efficient at eliminating waste by diffusion?

1/1/1

Which of the following components of the cell membrane is responsible for active transport?

Protein

What is the expected percent change in the content of a typical eukaryotic cell as it progresses through the cell cycle from the start of the phase to the end of the phase?

100%

What evolutionary advantage does compartmentalization of core metabolic processes offer eukaryotes?

Evolution of a nucleus in eukaryotes separates the processes of transcription and translation and they can be regulated separately.

A typical bag of fertilizer contains high levels of nitrogen, phosphorus, and potassium but trace amounts of magnesium and calcium. Which of the following best matches the fertilizer component with the molecule in which it will be incorporated by organisms in the area?

Nitrogen will be incorporated into nucleic acids.

Of the following, which additional investigation can be used to determine when the cells are in an isotonic solution?

Increasing the salinity of the environment a little at a time until the ATP usage reaches a minimum

Figure 1. Diagram of the electron transport chain and synthase in the membrane of mitochondria On average, more can be produced from an molecule than can be produced from a molecule of . Based on Figure 1, which of the following best explains the difference in production between these two molecules?

The electrons of FADH2 are transferred through three complexes of the electron transport chain whereas those of NADH are transferred through all four complexes.

Which of the following claims is best supported by the data from test 5 in Table 1 ?

Domain F is not required for protein-protein interaction.

Based on the data, which structural domain is most likely required for DNA binding?

Domain F

Which of the following claims is best supported by the data in Table 1 ?

Protein-protein interaction is necessary for, but not adequate for, transcriptional activation.

Which of the following is the most likely result of testing a combination of domains and ?

Protein-protein interaction only

Which of the following best explains how a drug can be used to inhibit tumor growth caused by EGF overexpression?

The drug binds to HER2, preventing the activation of the signaling pathway.

The hydrolytic enzymes are most likely to accumulate in which of the following cellular structures?

Golgi complex

Which of the following best predicts the effect of disrupting the proton gradient in ?

Electron transport and oxidative phosphorylation will be decoupled, generating more heat but less ATP.

Melanocytes are skin cells that can become cancerous and develop into a cancer known as melanoma. Some cancerous melanocytes have developed resistance to the drugs currently used to treat melanoma. As a result, researchers are investigating the effects of a new compound (drug X) on four different melanoma cell lines. Researchers analyzed cell survival in two cell lines (Figure 1) and oxygen consumption in the presence of drug X in all four cell lines (Figure 2). Figure 3 shows the proposed mechanism by which drug X affects cells.
Which of the following best describes the data in Figure 1 ?

At a concentration above μ10 μM, drug X reduces melanoma cell survival.

Based on Figure 2, which of the following best supports the claim that drug inhibits oxygen consumption?

Melanoma line 3 consumes statistically less oxygen per cell in the presence of drug X than it does in the presence of the solvent alone.

Based on Figure 1, which of the following best explains how exercise causes blood glucose levels to rise?

Epinephrine activates alpha cells, causing the release of glucagon, and inhibits beta cells, blocking the release of insulin.

Which of the following most directly explains the changes in the cells?

The movement of water from the central vacuoles of the cells into the solution.

If NAF is added to cells undergoing cellular respiration, which of the following will most likely accumulate in the cells?

2-phosphogylcerate

Based on Figure 1, the net number of ATP molecules produced during glycolysis from the metabolism of a single glucose molecule is closest to which of the following?

2

Which of the following is the best explanation for the pattern of change in mass of the organisms over time?

cellular respiration

Figure 1 shows a model of the endocrine signaling pathway that regulates ovulation. Which of the following observations would provide evidence of a positive feedback mechanism in this system?

Estrogen from the ovaries stimulates the hypothalamus and anterior pituitary to secrete more GnRH, LH, and FSH.

Which of the following statements best helps explain the reaction specificity of an enzyme?

The shape and charge of the substrates are compatible with the active site of the enzyme.

Which of the following best describes how an increase in the concentration of substrate in the reaction mixture affected the frequency of enzyme‑substrate interactions?

The frequency of enzyme-substrate interactions increased until all of the active sites were interacting with substrate.

Which of the following experimental designs would best allow researchers to investigate the effect of pH on the rate of the enzyme-catalyzed reaction?

Measure reaction rates at different pH levels when the enzyme concentration remains the same and the substrate concentration is μ100μM.

Which of the following questions best addresses whether a particular inhibitor is competitive or noncompetitive?

Does the inhibitor bind to an allosteric site or the active site of the enzyme?

Which of the following best explains how higher concentrations of nitrogen and phosphorus contribute to eutrophication?

Algae require nitrogen and phosphorus to build macromolecules, so higher concentrations of these nutrients can result in algal blooms.

Which of the following statements describes a feature shared by mitochondria and the endoplasmic reticulum that increases the efficiency of their basic functions?

They have highly folded membranes.

Which of the following would be the most appropriate control for this experiment?

A test tube containing a piece of exposed camera film submerged in water

Which of the following best explains how DCMU affected the reaction?

DCMU acts as an inhibitor to the movement of electrons within the light reaction of photosynthesis.

If ADH secretion is inhibited, which of the following would initially result?

The person would produce greater amounts of dilute urine.

Which of the following best explains the mechanism by which alanine inhibits pyruvate kinase activity?

Alanine binds to an allosteric site of the enzyme, changing the shape of the enzyme's active site.

Which of the following outcomes will most likely result from a change in the shape of the mitochondrial inner membrane from a highly folded surface to a smooth, flat surface?

Mitochondria will become less efficient because the surface area of the inner mitochondrial membranes will decrease.

Which of the following statements best describes how molecules released by the fish become nutrients for the plants?

The ammonia molecules released by the fish are converted by the bacteria to nitrates, which are used by the plants to make proteins and nucleic acids.

Based on Table 1, which of the following best explains the difference in water potential between certain solutions and the grapes?

Grape soda and NaCl have a lower water potential because these two solutions caused the grape to lose water.

Based on the model presented in Figure 1, which of the following outcomes will most likely result from a loss of protein X function?

The membrane potential will be disrupted by an increase in K+ concentration inside the cell.

Which of the following best explains the connection between energy, growth, and the maintenance of an ordered system in the experiment?

Energy input from light is required for the grass to grow and maintain an ordered structure.

Which of the following statements best helps explain how the enzyme speeds up the reaction?

The enzyme's active site binds to and stabilizes the transition state, which decreases the activation energy of the reaction.

The manner in which several different ions and molecules move through a cell membrane is shown in the diagram above. For each ion or molecule, the relative concentration on each side of the membrane is indicated. Which of the following accurately describes one of the movements taking place?

Na+ transport out of the cell requires ATP hydrolysis.

An investigator wants to understand whether a newly found membrane protein is involved in membrane transport of a certain particle. Which investigation will help determine whether the new membrane protein is a channel protein involved in membrane transport?

Add more of the proteins to the plasma membrane and measure the rate of the particle movement.

Which of the following statements best predicts the effect of increasing the concentration of substrate (ethyl alcohol), while keeping the concentration of the inhibitor (methyl alcohol) constant?

Competitive inhibition will decrease because the proportion of the active sites occupied by substrate will increase.

Which of the following best describes how the amount of DNA in the cell changes during phase?

The amount of DNA is halved as the cell divides into two daughter cells.

A researcher claims that increased atmospheric carbon dioxide levels cause increased growth rates in plants.

Which of the following statements best supports the researcher's claim?

Atmospheric carbon dioxide is the RAW material for photosynthesis, which plants rely on for producing sugars and other organic compounds.

Researchers performed an experiment to determine the effect of certain genetic mutations on mitosis in tropical fruit fly embryos. They determined the percentage of cells in each of four phases of mitosis as shown in Figure 1.

Which of the following patterns is shown by the data?

In mutant 3 cells, more time is spent in prophase/prometaphase than in the later stages of mitosis.

If chemical signals in the cytoplasm control the progression of a cell to the M phase of the cell cycle, then fusion of a cell in G1 with a cell in early M phase would most likely result in the

condensation of chromatin in preparation of nuclear division in both cells.

Which of the following describes the most likely location of cholesterol in an animal cell?

embedded in the plasma membrane.

A researcher designs an experiment to investigate the effect of environmental temperature on the function of an enzyme. For each trial included in the experiment, the researcher will add the enzyme and its substrate to an aqueous buffer solution and then measure the amount of product formed over 20 minutes.

Which of the following must remain the same for all trials of this experiment?

The initial concentration of the substrate

Damaged tissue releases chemicals that activate platelets and stimulate the formation of blood clots.
Which of the following predictions about the activity of platelets best describes a positive feedback mechanism?

Activated platelets release chemicals that activate more platelets.

Scientists investigated the effect of oxygen levels on the net rate of carbon fixation in two types of plants. The plants were grown in either well-watered soil (control) or dry soil and then exposed to either 21% or 1%. The net rate of CO2 fixation for both types of plants was measured. Data are shown in Figure 1 and Figure 2.

Which of the following statements about the rate of CO2 fixation in the two types of plants is supported by the data shown in the figures?

At 21% O2, plant type 2 has a lower rate of CO2 fixation than plant type 1 does in both types of soil.

Based on Figure 1, which of the following statements best describes the epinephrine signaling pathway?

The storage of GLUT4 in vesicles inside the cell will increase.

Which of the following is evidence that eukaryotes and prokaryotes share a common ancestor?

All eukaryotes and prokaryotes contain ribosomes.

Ethylene gas is an organic molecule that serves many cell signaling roles in flowering plants. Which of the following best explains how a positive feedback mechanism involving ethylene works?

cells of ripening fruit produce ethylene, which activates the ripening response in other fruit cells.

A scientist determined the rate of an enzyme-catalyzed reaction by measuring the amount of product formed over time. The following curve was generated from the data collected.

What is the most likely explanation for the change in the slope of the line between 3 and 5 minutes?

A large amount of the substrate had been consumed.

Researchers studying cell cycle regulation in budding yeast have observed that a mutation in the CDC15 gene causes cell cycle arrest in telophase when the yeast cells are incubated at an elevated temperature.

Which of the following statements best predicts the effect of the cell cycle arrest on proliferating yeast cells?

The yeast cells will replicate their chromosomes but will fail to complete cytokinesis.

A scientist determined the rate of an enzyme-catalyzed reaction by measuring the amount of product formed over time. The following curve was generated from the data collected.

The rate of the reaction could also be determined by

measuring the change in the amount of substrate.

Researchers determined the average amount of time that a particular type of eukaryotic cell spends in each phase of the cell cycle. The data collected by the researchers are represented in Figure 1. Figure 1. The average amount of time spent by a particular type of eukaryotic cell in each phase of the cell cycle

Based on Figure 1, what percent of the time required to complete a full cycle do the cells typically spend in interphase?

95%

Researchers have proposed a model of the process by which a newly synthesized protein is transported to the plasma membrane and secreted into the extracellular space. The model is represented in Figure 1. Figure 1. A model of the intracellular transport of a newly synthesized secreted protein

Based on the model, the newly synthesized protein is transported directly from the endoplasmic reticulum to which of the following?

The Golgi Complex

The enzyme trypsin aids in protein digestion in the small intestine. The relative activity of trypsin at different values is shown in Figure 1. Figure 1. Effect of on the activity of trypsin

Which of the following statements best explains the activity levels of trypsin shown in Figure 1 ?

At extremely low pH values, trypsin is denatured and cannot function efficiently.

Figure 1 is a diagram of water molecules at the air-water interface at the surface of a pond. Figure 1. Alignment of water molecules at air-water interface.

Based on Figure 1, which of the following best describes how the properties of water at an air-water interface enable an insect to walk on the water's surface?

Hydrogen bonds between molecules at the surface of the water provide surface tension, which allows the water surface to deform but not break under the insect..

Which of the following best describes the process by which gas from the atmosphere is obtained by plants and used to build lipids?

Gas is directly obtained by plants as part of the carbon cycle.

The diagram shows how water can adhere to the xylem in the stems of plants, which contributes to water movement in the plant.

Which of the following best explains how water is able to move upward from the roots of a plant, through its xylem in the stem, and out to the leaves?

Water and the xylem are both polar.

Which of the following best describes the structures of carbohydrates?

They occur as monomers, chains of monomers, and branched structures.

Which of the following groups of cellular components are found in eukaryotic cells but not prokaryotic cells?

An endoplasmic reticulum, mitochondria, and a nucleus

Humans produce sweat as a cooling mechanism to maintain a stable internal temperature.

Which of the following best explains how the properties of water contribute to this physiological process?

The high heat of vaporization of water allows the body to remove excess heat through a phase change of water from liquid to gas.

Which of the following questions is most relevant to understanding the Calvin cycle?

how does chlorophyll capture light?

A student placed a semipermeable membrane inside a U-shaped channel with two chambers, as shown. The membrane permits the movement of water but not salt. The student wants to vary the rate of osmosis that occurs across the membrane.

Which of the following experimental designs will result in the fastest net rate of water movement into chamber A?

Placing salt water in chamber A and distilled water in chamber B

In a certain signal transduction pathway, the binding of an extracellular molecule to a cell-surface protein results in a rapid increase in the concentration of cyclic AMP inside the cell. The cyclic AMP binds to and activates cytosolic enzymes that then activate other enzymes in the cell.

Which of the following statements best describes the role of cyclic AMP in the signal transduction pathway?

It acts as a second messenger that helps relay and amplify the signal within the cell.

Which of the following best describes the role of ATP and NADPH in the process of photosynthesis?

ATP and NADPH are carriers of chemical energy that is used in the production of carbohydrates.

Figure 1. Activity levels of two digestive enzymes over a range of PH Trypsin and pepsin are enzymes that function in different areas of the digestive tract. One functions in the stomach, where the pH is between 1.5 and 3.5, while the other functions in the small intestines, where the pH is between 6 and 8 .

Based on Figure 1, which of the following best describes where each enzyme functions?

Pepsin works in the stomach because the optimal pH for pepsin is acidic.

A researcher claims that different enzymes exhibit maximal function over different pH ranges. To test the claim, the researcher carries out an experiment that includes three different enzymes: pepsin, salivary amylase, and arginase. The results of the experiment are represented in Figure 1. Figure 1. The effect of on three different enzymes

Which of the following actions will provide the most appropriate negative control for the experiment?

Repeating the experiment with denatured enzymes.

Figure 1 represents a common process that occurs in organisms. Figure 1. Structural formula for a common biological reaction

Which of the following is an accurate description of the process shown in Figure 1 ?

The formation of a covalent peptide bond in a dehydration synthesis reaction.