AP Biology Midterm Review – Previous Test Questions

AP Biology - Chap 3-6 Assessment

Multiple Choice

Identify the choice that best completes the statement or answers the question.

____1)In a plant cell, DNA may be found ____.

A) / in the nucleus, mitochondria, chloroplasts, and peroxisomes
B) / only in the nucleus and chloroplasts
C) / only in the nucleus
D) / in the nucleus, mitochondria, and chloroplasts

____2)Which of the following is present in a prokaryotic cell?

A) / ribosome
B) / mitochondrion
C) / chloroplast
D) / ER

____3)Phospholipids and triglycerides both ____.

A) / have three fatty acids
B) / have a glycerol backbone
C) / have a phosphate
D) / contain serine or some other organic compound

____4)Which of the following is the strongest evidence that protein structure and function are correlated?

A) / Enzymes tend to be globular in shape.
B) / Proteins function best at certain temperatures.
C) / Proteins have four distinct levels of structure and many functions.
D) / Denatured (unfolded) proteins do not function normally.

____5)A solution with a pH of 5 has how many more protons in it than a solution with a pH of 7?

A) / 10 times
B) / 100 times
C) / 5 times
D) / 1000 times

____6)Suppose a young boy is always tired and fatigued, suffering from a metabolic disease. Which of the following organelles is most likely involved in this disease?

A) / mitochondria
B) / ribosomes
C) / Golgi apparatus
D) / lysosomes

____7)If one strand of a DNA molecule has the sequence of bases 5'ATTGCA3', the other complementary strand would have the sequence ____.

A) / 5'UGCAAU3'
B) / 3'UAACGU5'
C) / 5'TAACGT3'
D) / 5'TGCAAT3'

____8)Where are proteins produced other than on ribosomes free in the cytosol or ribosomes attached to the ER?

A) / in the extracellular matrix
B) / in the Golgi apparatus
C) / in the nucleolus
D) / in mitochondria

____9)One of the buffers that contribute to pH stability in human blood is carbonic acid (H2CO3). Carbonic acid is a weak acid that, when placed in an aqueous solution, dissociates into a bicarbonate ion (HCO3-) and a hydrogen ion (H+), as noted below.

If the pH of blood drops, one would expect ____.

A) / the HCO3- to act as an acid and remove excess H+ by the formation of H2CO3
B) / the concentration of bicarbonate ions (HCO3-) to increase
C) / a decrease in the concentration of H2CO3 and an increase in the concentration of HCO3-
D) / the HCO3- to act as a base and remove excess H+ by the formation of H2CO3

____10)Spherocytosis is a human blood disorder associated with a defective cytoskeletal protein in the red blood cells (RBCs). What do you suspect is the consequence of such a defect?

A) / adherence of RBCs to blood vessel walls, causing plaque formation
B) / abnormally shaped RBCs
C) / an insufficient supply of oxygen-transporting proteins in the RBCs
D) / an insufficient supply of ATP in the RBCs

____11)Researchers tried to explain how vesicular transport occurs in cells by attempting to assemble the transport components. They set up microtubular tracks along which vesicles could be transported, and they added vesicles and ATP (because they knew the transport process requires energy). Yet, when they put everything together, there was no movement or transport of vesicles. What were they missing?

A) / an axon
B) / contractile microfilaments
C) / endoplasmic reticulum
D) / motor proteins

____12)What is the term used for a protein molecule that assists in the proper folding of other proteins?

A) / renaturing protein
B) / tertiary protein
C) / chaperonin
D) / denaturing protein

____13)Stanley Miller's 1953 experiments supported the hypothesis that ____.

A) / life on Earth arose from simple inorganic molecules
B) / the conditions on early Earth were conducive to the origin of life
C) / life on Earth arose from simple organic molecules, with energy from lightning and volcanoes
D) / organic molecules can be synthesized abiotically under conditions that may have existed on early Earth

____14)What is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell?

A) / Golgi  ER  lysosome
B) / ER  lysosomes  vesicles that fuse with plasma membrane
C) / ER  Golgi  vesicles that fuse with plasma membrane
D) / ER  Golgi  nucleus

____15)Which one of the following is NOT a component of each monomer used to make proteins?

A) / a side chain, R
B) / a carboxyl group, COOH
C) / an amino functional group, NH2
D) / a phosphorus atom, P

____16)Which of the following takes place as an ice cube cools a drink?

A) / Kinetic energy in the liquid water decreases.
B) / A calorie of heat energy is transferred from the ice to the water of the drink.
C) / The specific heat of the water in the drink decreases.
D) / Molecular collisions in the drink increase.

____17)The R-group, or side chain, of the amino acid serine is -CH2-OH. The R-group, or side chain, of the amino acid leucine is -CH2-CH-(CH3)2. Where would you expect to find these amino acids in a globular protein in aqueous solution?

A) / Serine would be in the interior, and leucine would be on the exterior of the globular protein.
B) / Serine and leucine would both be on the exterior of the globular protein.
C) / Serine and leucine would both be in the interior of the globular protein.
D) / Leucine would be in the interior, and serine would be on the exterior of the globular protein.

____18)Suppose a cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and mitochondria. It could be a cell from ____.

A) / a bacterium
B) / an animal but not a plant
C) / nearly any eukaryotic organism
D) / a plant but not an animal

____19)Humans can digest starch but not cellulose because ____.

A) / starch monomers are joined by covalent bonds and cellulose monomers are joined by ionic bonds
B) / the monomer of starch is glucose, while the monomer of cellulose is galactose
C) / the monomer of starch is fructose, while the monomer of cellulose is glucose
D) / humans have enzymes that can hydrolyze the -glycosidic linkages of starch but not the -glycosidic linkages of cellulose

____20)Which of the following molecules is polar?

C3H7OH C2H5COOH

A) / C2H5COOH is polar, but C3H7OH is not polar.
B) / C3H7OH is not polar, but C3H7OH is polar.
C) / C3H7OH and C2H5COOH are both polar molecules.
D) / Neither C2H5COOH or C3H7OH is polar.

AP Test Style

1)

The water molecules in the diagram are attracted to the cell walls of water-conducting cells by adhesion due to hydrogen bonds. What conclusion is supported by this information?

A) / Cell walls of plants are composed of non-polar molecules.
B) / Cell walls of plants contain molecular grooves that physically hold the water molecule.
C) / Cell walls of plants contain oxygen and/or nitrogen and are therefore polar.
D) / Cell walls of plants are formed from the products of photosynthesis.

Essay

1)No cell can function without the basic requirements. Certain organelles are required for basic life functions. It is known that cell organelles are associated closely to many carbon macromolecules.

A) List the 4 molecules/organelles that ALL living organisms must have include as part of their cells to survive.

B) Choose two of those molecules/organelles and explain how they are tied directly to at least one of the four carbon compounds.

AP Bio - Chap 7 and 11 quiz

Multiple Choice

Identify the choice that best completes the statement or answers the question.

____1)Why is apoptosis potentially threatening to the healthy "neighbors" of a dying cell?

A) / Cell death would usually spread from one cell to the next via paracrine signals.
B) / Lysosomal enzymes exiting the dying cell would damage surrounding cells.
C) / Bits of membrane from the dying cell could merge with neighboring cells and bring in foreign receptors.
D) / Neighboring cells would activate immunological responses.

____2)Lipid-soluble signaling molecules, such as testosterone, cross the membranes of all cells but affect only target cells because ____.

A) / only target cells retain the appropriate DNA segments
B) / intracellular receptors are present only in target cells
C) / only target cells possess the cytosolic enzymes that transduce the testosterone
D) / only in target cells is testosterone able to initiate the phosphorylation cascade leading to activated transcription factor

____3)Which of the following most accurately describes selective permeability?

A) / An input of energy is required for transport.
B) / Lipid-soluble molecules pass through a membrane.
C) / There must be a concentration gradient for molecules to pass through a membrane.
D) / Only certain molecules can cross a cell membrane.

____4)Phosphorylation cascades involving a series of protein kinases are useful for cellular signal transduction because they ____.

A) / are species specific
B) / always lead to the same cellular response
C) / amplify the original signal many times
D) / counter the harmful effects of phosphatases

____5)At puberty, an adolescent female body changes in both structure and function of several organ systems, primarily under the influence of changing concentrations of estrogens and other steroid hormones. How can one hormone, such as estrogen, mediate so many effects?

A) / Estrogen is produced in very large concentration by nearly every tissue of the body.
B) / Each cell responds in the same way when steroids bind to the cell surface.
C) / Estrogen is kept away from the surface of any cells not able to bind it at the surface.
D) / Estrogen binds to specific receptors inside many kinds of cells, each with different responses.

____6)In receptor-mediated endocytosis, receptor molecules initially project to the outside of the cell. Where do they end up after endocytosis?

A) / on the outside of vesicles
B) / on the inside surface of the cell membrane
C) / on the inside surface of the vesicle
D) / on the outer surface of the nucleus

____7)Protein kinase is an enzyme that ____.

A) / functions as a second messenger molecule
B) / serves as a receptor for various signal molecules
C) / activates or inactivates other proteins by adding a phosphate group to them
D) / produces second messenger molecules

____8)Consider this pathway: epinephrine  G protein-coupled receptor  G protein  adenylyl cyclase  cAMP. The second messenger in this pathway is ____.

A) / cAMP
B) / G protein
C) / adenylyl cyclase
D) / G protein-coupled receptor

____9)What will happen to a red blood cell (RBC), which has an internal ion concentration of about 0.9 percent, if it is placed into a beaker of pure water?

A) / The cell would shrink because the water in the beaker is hypotonic relative to the cytoplasm of the RBC.
B) / The cell would shrink because the water in the beaker is hypertonic relative to the cytoplasm of the RBC.
C) / The cell would swell because the water in the beaker is hypotonic relative to the cytoplasm of the RBC.
D) / The cell will remain the same size because the solution outside the cell is isotonic.

____10)When a neuron responds to a particular neurotransmitter by opening gated ion channels, the neurotransmitter is serving as which part of the signal pathway?

A) / relay molecule
B) / transducer
C) / signal molecule
D) / response molecule

____11)One of the major categories of receptors in the plasma membrane reacts by forming dimers, adding phosphate groups, and then activating relay proteins. Which type does this?

A) / G protein-coupled receptors
B) / ligand-gated ion channels
C) / steroid receptors
D) / receptor tyrosine kinases

____12)Which of the following is a type of local signaling in which a cell secretes a signal molecule that affects neighboring cells?

A) / hormonal signaling
B) / autocrine signaling
C) / paracrine signaling
D) / synaptic signaling

____13)The difference between pinocytosis and receptor-mediated endocytosis is that ____.

A) / pinocytosis brings only water molecules into the cell, but receptor-mediated endocytosis brings in other molecules as well.
B) / pinocytosis increases the surface area of the plasma membrane, whereas receptor-mediated endocytosis decreases the plasma membrane surface area.
C) / pinocytosis is nonselective in the molecules it brings into the cell, whereas receptor-mediated endocytosis offers more selectivity.
D) / pinocytosis can concentrate substances from the extracellular fluid, but receptor-mediated endocytosis cannot.

____14)A bacterium engulfed by a white blood cell through phagocytosis will be digested by enzymes contained in ____.

A) / lysosomes
B) / Golgi vesicles
C) / vacuoles
D) / secretory vesicles

____15)Which of the following processes includes all others?

A) / osmosis
B) / facilitated diffusion
C) / passive transport
D) / transport of an ion down its electrochemical gradient

____16)When a plant cell, such as one from a rose stem, is submerged in a very hypotonic solution, what is likely to occur?

A) / The cell will burst.
B) / Plasmolysis will shrink the interior.
C) / The cell will become flaccid.
D) / The cell will become turgid.

____17)Which of the following would be inhibited by a drug that specifically blocks the addition of phosphate groups to proteins?

A) / G protein-coupled receptor binding
B) / ligand-gated ion channel signaling
C) / adenylyl cyclase activity
D) / receptor tyrosine kinase activity

____18)Which of the following membrane activities requires energy from ATP?

A) / facilitated diffusion of chloride ions across the membrane through a chloride channel
B) / movement of Na+ ions from a lower concentration in a mammalian cell to a higher concentration in the extracellular fluid
C) / movement of glucose molecules into a bacterial cell from a medium containing a higher concentration of glucose than inside the cell
D) / movement of carbon dioxide out of a paramecium

Five dialysis bags constructed of membrane, which is permeable to water and impermeable to sucrose, were filled with various concentrations of sucrose and then placed in separate beakers containing an initial concentration of 0.6 M sucrose solution. At 10-minute intervals, the bags were massed (weighed) and the percent change in mass of each bag was graphed.

____19)Which line in the graph represents the bag that contained a solution isotonic to the 0.6 M solution at the beginning of the experiment?

A) / A
B) / B
C) / C
D) / D

____20)In general, a signal transmitted via phosphorylation of a series of proteins ____.

A) / results in a conformational change to each protein
B) / requires binding of a hormone to an intracellular receptor
C) / activates a transcription event
D) / generates ATP in the process of signal transduction

AP Biology - Chap 8-10 Energy, Photosynthesis and Respiration

Multiple Choice

Identify the choice that best completes the statement or answers the question.

____1)

Rate of an enzyme-catalyzed reaction as a function of varying reactant

concentration, with the concentration of enzyme constant.

In the figure, why does the reaction rate plateau at higher reactant concentrations?

A) / The rate of the reverse reaction increases with reactant concentration.
B) / Most enzyme molecules are occupied by substrate at high reactant concentrations.
C) / Feedback inhibition by product occurs at high reactant concentrations.
D) / The reaction nears equilibrium at high reactant concentrations.

____2)You have a friend who lost 7 kg (about 15 pounds) of fat on a regimen of strict diet and exercise. How did the fat leave his body?

A) / It was converted to heat and then released.
B) / It was released as CO2 and H2O.
C) / It was converted to ATP, which weighs much less than fat.
D) / It was converted to urine and eliminated from the body.

____3)Which of the following statements best describes the relationship between photosynthesis and respiration?

A) / Respiration runs the biochemical pathways of photosynthesis in reverse.
B) / Photosynthesis occurs only in plants; respiration occurs only in animals.
C) / Photosynthesis stores energy in complex organic molecules; respiration releases energy from complex organic molecules
D) / Photosynthesis is catabolic; respiration is anabolic.

____4)Which term most precisely describes the cellular process of breaking down large molecules into smaller ones?

A) / catabolism (catabolic pathways)
B) / anabolism (anabolic pathways)
C) / dehydration
D) / metabolism

Use the following information to answer the questions below.

Succinate dehydrogenase catalyzes the conversion of succinate to fumarate. The reaction is inhibited by malonic acid, which resembles succinate but cannot be acted upon by succinate dehydrogenase. Increasing the ratio of succinate to malonic acid reduces the inhibitory effect of malonic acid.

____5)HIV is the virus that causes AIDS. In the mid-1990s, researchers discovered an enzyme in HIV called protease. Once the enzyme's structure was known, researchers began looking for drugs that would fit into the active site and block it. If this strategy for stopping HIV infections were successful, it would be an example of what phenomenon?

A) / competitive inhibition
B) / denaturation
C) / vaccination
D) / allosteric regulation

____6)During a laboratory experiment, you discover that an enzyme-catalyzed reaction has a G of -20 kcal/mol. If you double the amount of enzyme in the reaction, what will be the G for the new reaction?

A) / -20 kcal/mol
B) / +20 kcal/mol
C) / -40 kcal/mol
D) / 0 kcal/mol

____7)Carbohydrates and fats are considered high-energy foods because they ____.

A) / have a lot of electrons associated with hydrogen.
B) / have no nitrogen in their makeup.
C) / have a lot of oxygen atoms.
D) / are easily reduced.

____8)Substrate-level phosphorylation occurs ____.

A) / in both glycolysis and the citric acid cycle
B) / in the citric acid cycle
C) / in glycolysis
D) / during oxidative phosphorylation

____9)The process of photosynthesis probably originated ____.

A) / in fungi
B) / three separate times during evolution
C) / in prokaryotes
D) / in plants

____10)The primary role of oxygen in cellular respiration is to ____.

A) / act as an acceptor for electrons and hydrogen, forming water
B) / combine with carbon, forming CO2
C) / yield energy in the form of ATP as it is passed down the respiratory chain
D) / combine with lactate, forming pyruvate

____11)Why is ATP an important molecule in metabolism?

A) / It provides energy coupling between exergonic and endergonic reactions.
B) / Its terminal phosphate group contains a strong covalent bond that, when hydrolyzed, releases free energy.
C) / Its terminal phosphate bond has higher energy than the other two phosphate bonds.
D) / Its hydrolysis provides an input of free energy for exergonic reactions.

____12)Which kind of metabolic poison would most directly interfere with glycolysis?

A) / an agent that closely mimics the structure of glucose but is not metabolized
B) / an agent that binds to pyruvate and inactivates it
C) / an agent that reacts with oxygen and depletes its concentration in the cell
D) / an agent that reacts with NADH and oxidizes it to NAD+

____13)A young dog has never had much energy. He is brought to a veterinarian for help and she decides to conduct several diagnostic tests. She discovers that the dog's mitochondria can use only fatty acids and amino acids for respiration, and his cells produce more lactate than normal. Of the following, which is the best explanation of the dog's condition?

A) / His mitochondria lack the transport protein that moves pyruvate across the outer mitochondrial membrane.
B) / His cells lack the enzyme in glycolysis that forms pyruvate.
C) / His cells have a defective electron transport chain, so glucose goes to lactate instead of to acetyl CoA.
D) / His cells cannot move NADH from glycolysis into the mitochondria.

____14)Which of the following involves a decrease in entropy?