Exam Questions Multiple Choice Flashcards
The molecules responsible for membrane transport are
A) steroids.
B) phospholipids.
C) carbohydrates.
D) proteins
D proteins
Bonds that are formed between oxygen and hydrogen atoms within water molecules are called .
A) hydrogen bonds
B) ionic bonds
C) nonpolar covalent bonds
D) polar covalent bonds
polar covalent bonds
Which of the following would be most easily broken?
A) A hydrogen bond
B) A nonpolar covalent bond
C) An ionic bond
D) A polar covalent bond
A hydrogen bond
In an acidic solution, .
A) the OH- ion concentration is greater than the H+ ion concentration
B) the OH- ion concentration is less than the H+ ion concentration
C) the H+ ion concentration is equal to the OH- ion concentration
D) the H+ ion concentration is less than the OH- ion concentration only if the solution is buffered
the OH- ion concentration is less than the H+ ion concentration
Which of the following is false regarding unsaturated fatty acids?
A) They contain one or more double bonds.
B) They are found in cooking oil rather than a stick of butter.
C) All of their hydrogen ions are occupied in double bonds.
D) They can be formed from nuts and other plants.
All of their hydrogen ions are occupied in double bonds.
The base that is NOT found in RNA is .
A) thymine
B) guanine
C) cytosine
D) uracil
Thymine
Which of the following is NOT a difference between DNA and RNA?
A) They have different sugars.
B) RNA is a single strand, while DNA is a double strand.
C) DNA has thymine, while RNA has uracil.
D) They both can leave the nucleus to perform their functions.
They both can leave the nucleus to perform their functions.
A cell which is actively involved in the detoxification of chemicals would contain large quantities of .
A) ribosomes
B) mitochondria
C) peroxisomes
D) rough endoplasmic reticulum
peroxisomes
Which of the following statements about enzymes is FALSE?
A) Enzymes increase chemical reaction rates.
B) Enzymes are consumed during a chemical reaction.
C) Enzymes decrease the free energy of activation of specific reactions.
D) Enzymes have unique pH and temperature optima.
Enzymes are consumed during a chemical reaction.
When an enzyme catalyzes a chemical reaction, .
A) the enzyme binds to the substrate’s active site
B) the enzyme’s active site binds to the product
C) amino acids in the substrate allow for interaction with the product
D) amino acids in the enzyme’s active site interact with substrate molecules to create a product
amino acids in the enzyme’s active site interact with substrate molecules to create a product
Addition of phosphate groups to a particular molecule is catalyzed by .
A) transaminases
B) phosphatases
C) isomerases
D) kinases
kinases
Anabolic reactions do not .
A) utilize energy
B) synthesize molecules within cells
C) store energy
D) release energy
release energy
Glycolysis converts glucose into two molecules.
A) glycogen
B) lactic acid
C) acetyl CoA
D) pyruvic acid
pyruvic acid
To form lactic acid from pyruvic acid it is necessary to have present.
A) NAD
B) FAD
C) NADH
D) FADH
NADH
The final electron acceptor in the electron transport chain system is .
A) NAD
B) hydrogen
C) oxygen
D) ATP
Oxygen
What theory explains the ability of the electron transport system to pump protons between the inner and outer mitochondrial membranes?
A) Tricarboxylic acid theory
B) Chemiosmotic theory
C) Phosphorylation theory
D) Proton pump theory
Chemiosmotic theory
The opposite process of glycogenesis is .
A) glycolysis
B) glyconeogenesis
C) glycogenolysis
D) gluconeogenesis
glycogenolysis
Which of the following can undergo metabolic conversion to acetyl CoA and enter the citric acid cycle?
A) Glucose
B) Fatty acids
C) Protein
D) All of the choices are correct.
All of the choices are correct
A solution consists of a which dissolves the .
A) solvent, solute
B) solvent, solid
C) solute, solvent
D) liquid, solid
solvent, solute
Osmotic pressure is a measure of the force needed to .
A) open aquaporins
B) cause osmosis
C) stop osmosis
D) stop edema
stop osmosis
Facilitated diffusion of a molecule into a cell would be more rapid if the .
A) concentration of the molecule in the cell increased
B) concentration of water in the cell decreased
C) concentration of the molecule outside the cell increased
D) cell was isotonic
concentration of the molecule outside the cell increased
The process that produces the most ATP molecules per molecule of glucose is
A) substrate-level phosphorylation.
B) oxidative phosphorylation.
C) anaerobic glycolysis.
D) aerobic glycolysis.
E) Krebs (citric acid) cycle.
oxidative phosphorylation.
The diffusion rate of chemical X across a cell membrane can be increased by
A) decreasing the membrane permeability of X.
B) decreasing the concentration gradient for X across the membrane.
C) increasing the area of diffusion.
D) increasing the thickness of the membrane.
increasing the area of diffusion.
Addition of substrate when enzyme reaction rate is maximal results in .
A) additional product formation
B) less product formation
C) no change in product formation
D) enzyme destruction
no change in product formation
Anything that prevents ATP formation will most likely
A) result in cell death.
B) force the cell to rely on lipids for energy.
C) force the cell to rely on ADP for energy.
D) have no effect on the cell.
Results in cell death
Choose the statement that accurately describes why catalysts are biologically necessary.
A) Catalysts provide the heat necessary for molecules to reach activation energy.
B) Catalysts increase the activation energy of large populations of molecules.
C) Catalysts make reactions go faster without cellular damage that would occur from heat.
D) All cell processes would occur without catalysts, but catalysts optimize the reaction rates.
Catalysts make reactions go faster without cellular damage that would occur from heat.
Organic acids will contain .
A) a carboxyl group
B) a carbonyl group
C) an amino group
D) a hydroxyl group
a carboxyl group
A membrane that allows only certain molecules to pass through it is called .
A) selectively permeable
B) permeable
C) porous
D) countertransport
selectively permeable
Protein carrier-mediated transport of molecules display .
A) specificity
B) competition
C) saturation
D) All of the choices are correct.
All
The electron transport system is a series of reactions.
A) composition-decomposition
B) dehydration synthesis-hydrolysis
C) oxidation-reduction
D) reversible
oxidation-reduction
Which of the following types of transport does not require membrane proteins?
A) Facilitated diffusion
B) Bulk
C) Simple diffusion
D) Active
Simple diffusion
In a scientific experiment, a control group .
A) is less important than an experimental group
B) is used for comparison with the experimental group
C) makes the experiment better, but is not essential
D) all of the above are correct
is used for comparison with the experimental group
The first step in the scientific method involves the formation of a(n) .
Hypothesis
When an atom loses one or more electrons, it .
A) becomes positively charged
B) becomes negatively charged
C) is called an anion
D) has no change in its charge
becomes positively charged
Hydrophobic molecules would contain bonds.
A) nonpolar covalent
B) polar covalent
C) hydrogen
D) ionic
nonpolar covalent
Molecules that contain carbon and hydrogen atoms are .
A) ionic
B) inorganic
C) organic
D) carbonic
organic
The primary structure of proteins is .
A) the linear arrangement of amino acids in the molecule
B) alpha helix coils and beta-pleated sheet folds of a protein strand
C) due to the interaction between protein subunits
D) stabilized when a protein is denatured
the linear arrangement of amino acids in the molecule
The “spiral staircase” structure of DNA is referred to as the
Double helix
Folds of the plasma membrane that increase surface area are called .
A) cilia
B) microvilli
C) flagella
D) vesicles
microvilli
The organelle that acts as enzymes for protein synthesis is the .
A) mitochondrion
B) ribosome
C) nucleolus
D) lysosome
ribosome
The function of the is to produce ribosomal RNA.
A) chromatin
B) centromere
C) lysosomes
D) nucleolus
nucleolus
Which of the following is NOT a function of the Golgi complex?
A) Packaging final proteins in vesicles
B) Modifying proteins
C) Separation of different types of proteins
D) Removal of the leader sequence from the protein
E) cell cycle
Removal of the leader sequence from the protein
A chemical reaction rate can be increased by either the temperature or
the activation energy.
A) increasing; increasing
B) increasing; decreasing
C) decreasing; decreasing
D) decreasing; increasing
increasing; decreasing
The model that explains how an enzyme and substrate fit together is called the .
A) enzyme-substrate model
B) lock-and-key model
C) conformational model
D) induced-fit model
Lock and key model
In an enzymatic reaction, when temperature is increased past the point of “optimal temperature,” the enzyme starts to .
A) increase its catalytic activity
B) reduce its catalytic activity
C) increase its allosteric properties
D) increase product formation
reduce its catalytic activity
The final electron acceptor in aerobic cell respiration is .
A) water
B) oxygen
C) carbon dioxide
D) ATP
oxygen
Each turn of the citric acid cycle directly produces molecule(s) of ATP.
One
The yield of ATP from 1 molecule of glucose is .
A) about 20 ATP
B) about 38 ATP
C) about 30 ATP
D) about 26 ATP
B) about 38 ATP
What type of tissue is especially dependent on adequate plasma glucose levels?
A) Skeletal muscle
B) Cardiac muscle
C) Nervous
D) Liver
Nervous
Passive transport of water is known as .
A) filtration
B) osmosis
C) facilitated diffusion
D) a water pump
osmosis
Active transport carriers are also called .
A) vesicles
B) channels
C) pumps
D) receptors
Pumps
Choose the correct description of the Na+/K+ pump.
A) It is an example of primary active transport.
B) It generates a positive membrane potential.
C) It actively transports 2 potassium ions out of the cell.
D) It actively transports 3 sodium ions into the cell.
It is an example of primary active transport.
Secondary active transport .
A) utilizes energy directly
B) often utilizes symport proteins
C) always uses the influx of sodium ions
D) is only important in the kidney
often utilizes symport proteins
