BIOL 1009 Midterm 1 Study questions

ATP + H2O ---> ADP + Pi. This reaction Select one: a. yields useful energy to cells. b. is an endergonic reaction. c. is a dehydration reaction d. is a condensation reaction.

A

An enzyme's specificity is dependent on the Select one: a. tertiary structure of the enzyme. b. temperature of the reaction. c. substrates of the reaction. d. free energy of the reaction.

A

Glycerol is a component part of Select one: a. phospholipids. b. polysaccharides. c. proteins. d. nucleic acids.

A

The order of chemical bonds from easiest to hardest to break is Select one: a. van der Waals interactions, hydrogen bonds, ionic bonds, covalent bonds b. ionic bonds, covalent bonds, hydrogen bonds, van der Waals interactions c. covalent bonds, ionic bonds, hydrogen bonds, van der Waals interactions d. covalent bonds, ionic bonds, van der Waals interactions, hydrogen bonds

A

Vacuoles may act as Select one: a. places to store reserves of important organic molecules b. all of these answers are correct c. sites of lipid biosynthesis d. sites of protein biosynthesis

A

Which of the following best summarizes the relationship between dehydration reactions and hydrolysis? Select one: a. All of these answers are correct b. Dehydration reactions assemble polymers and hydrolysis reactions break down polymers. c. Macromolecular synthesis occurs through the removal of water and digestion occurs through the addition of water. d. Dehydration reactions generally occur during anabolism and hydrolysis reactions generally occur during catabolism.

A

Which of the following is NOT an example of discovery science? Select one: a. Testing the prediction that mimicking the coloring of poisonous snakes will protect non-poisonous snakes from predation. b. Observations that led to the conclusion that all organism are made of cells c. Some of Jane Goodall's work observing chimpanzee behavior d. Some of Charles Darwin's work that helped lead to the theory of natural selection

A

Which of the following membrane activities do NOT require energy from ATP hydrolysis? Select one: a. all of these answers are correct b. movement of solutes by carrier proteins c. passive diffusion d. movement of solutes by channel proteins

A

Which of the following statements about the Golgi apparatus is TRUE? Select one: a. Vesicles that bud off from the trans side of the Golgi apparatus have molecules on their surfaces that can recognize "docking" sites on the surface of the plasma membrane. b. Vesicles that bud off from the trans side of the Golgi apparatus always travel to the plasma membrane. c. Vesicles that bud off from the cis side of the Golgi apparatus have molecules on their surfaces that can recognize "docking" sites on the surface of the plasma membrane. d. Vesicles that bud off from the cis side of the Golgi apparatus always travel to the plasma membrane.

A

Which of the following statements concerning catabolic pathways is TRUE? Select one: a. They are usually coupled with anabolic pathways to which they supply energy in the form of ATP. b. They are endergonic. c. They combine molecules into more energy-rich foods. d. They are spontaneous and do not need enzyme catalysis.

A

For the reaction described in the figure shown below, which of the following represents the activation energy for the noncatalyzed reaction? Select one: a. arrow C b. arrow E c. arrow A d. arrow B

A. Arrow C

According to the second law of thermodynamics, a reaction that has a large negative ΔG: Select one: a. always has a large entropy value. b. is exergonic and will yield energy. c. is endergonic and will require energy to proceed. d. is spontaneous and will occur in a few seconds.

B

All of the following are part of a prokaryotic cell except Select one: a. a plasma membrane b. an endoplasmic reticulum c. ribosomes d. DNA

B

DNA is usually found in a double-stranded state. The two strands are held together by Select one: a. ionic bonds between the phosphate groups of one strand and the bases of the other. b. hydrogen bonds between the bases of one strand and the complementary bases of the other. c. covalent bonding of one strand's bases to the complementary base of the other. d. ionic bonds between the sugars of one strand and the phosphate groups of the other.

B

In the reaction of A + B ---> C , the forward reaction has a negative value of ΔG. This means that the reaction Select one: a. has the thermodynamic potential to proceed from right to left, but in the other direction upon the addition of free energy. b. has the thermodynamic potential to proceed from left to right, but in the other direction upon the addition of free energy. c. will go in either direction spontaneously. d. will require free energy input no matter which direction it is proceeding.

B

Ions and large polar molecules do not readily diffuse through the phospholipid bilayer of the cell membrane because the Select one: a. ions and molecules become entangled in the carbohydrate chains of the glycocalyx. b. fatty acid tails of the bilayer form a hydrophobic barrier. c. polar head groups of the bilayer form a hydrophilic barrier. d. bilayer is a rigid and impenetrable barrier.

B

Scientists choose among competing hypotheses by Select one: a. proving which hypothesis is true. b. discarding those hypotheses that make false predictions. c. selecting two or three of the most popular logical hypotheses, and voting on which is most popular. Incorrect d. keeping the hypothesis that is the most logical and discarding the rest.

B

Use the diagram below to help answer this question. The diagram shows a U-tube, with the two arms of the tube separated at the bottom by a semi-permeable barrier. This semi-permeable barrier is permeable to water and glucose, but not to sucrose. If you add 1 liter of an aqueous solution containing 2 moles of sucrose and 1 mole of glucose to side "A" of the tube, and 1 liter of an aqueous solution containing 1 mole of sucrose and 2 moles of glucose to side "B" of the tube, after the system reaches equilibrium, what changes are observed?

B

Which of the following statements is FALSE? Select one: a. Hydroxyl groups can form hydrogen bonds. b. sulfhydryl groups act as bases. c. Carboxyl groups tend to act as acids. d. Amino groups tend to act as bases.

B

For the reaction described in the figure shown below, which of the following would be the same in an enzyme-catalyzed or noncatalyzed reaction? Select one: a. arrow A b. arrow D c. arrow C d. arrow B

B. Arrow D

A particular molecule has a single carbon atom, which is covalently bound to four other atoms. The four atoms to which the carbon atom is bound are each from a different element. In other words, the molecule has a total of five atoms, each from a different element, one of which is carbon. Which of the following statements about this molecule is (are) true? Select one: a. It would be theoretically possible to design a molecule that would be a geometric isomer of the above molecule. b. It would be theoretically possible to design a molecule that would be a structural isomer of the above molecule. c. It would be theoretically possible to design a molecule that would be an enantiomer of the above molecule. d. None of these statements are true.

C

Cellulose is Select one: a. easily digested by enzymes found in all animals. b. a simple sugar. c. a polysaccharide found in plant cell walls. d. a major storage form of energy in animals.

C

Hydrogen bonds form between the hydrogen atoms of water molecules and Select one: a. hydrogen atoms of other water molecules. b. non-polar molecules more readily than polar molecules. c. oxygen atoms of other water molecules. d. oxygen atoms of hydrocarbons.

C

Of the following, the greatest electronegativity would be exhibited by an atom having Select one: a. four protons in its nucleus and two electrons in its second electron shell. b. six protons in its nucleus and four electrons in its second electron shell. c. nine protons in its nucleus and seven electrons in its second electron shell. d. three protons in its nucleus and one electron in its second electron shell.

C

The function of the nucleolus is the Select one: a. synthesis of DNA. b. packaging of cell material. c. synthesis of ribosomes. d. synthesis of lipid.

C

The ionic bond of sodium chloride is formed when Select one: a. sodium and chlorine share an electron pair. b. sodium and chlorine both lose electrons from their outer energy levels. c. chlorine gains an electron from sodium. d. sodium gains an electron from chlorine.

C

The mathematical expression for the change in the free energy of a system is ∆G = ∆H - T∆S. Which of the following is (are) TRUE? Select one: a. T is the temperature in degrees Celsius. b. ∆S is the change in enthalpy. c. ∆G is the change in free energy. d. ∆H is the change in entropy.

C

The pH in a cellular compartment is lowered from pH=7 to pH=5. The effect on proteins in this compartment will be Select one: a. negligible because the change is only 2 pH units. b. negligible because proteins have 4 levels of structure that will keep them stable. c. important because the hydrogen ion concentration has increased 100-fold and protein conformation will probably be altered. d. important because the hydrogen ion concentration has decreased 100-fold and protein conformation will probably be altered.

C

The proteins found in chloroplasts Select one: a. are encoded only by DNA in the chloroplast b. are encoded only by DNA in the nucleus c. are encoded either by DNA in the chloroplast or by nuclear DNA d. are encoded by DNA in the chloroplast, nucleus or mitochondria

C

When an electron moves from a lower energy level to a higher one, it Select one: a. forms a bond with a proton in the nucleus. b. transforms the atom from one isotope to another. c. absorbs energy. d. radiates energy.

C

Which of the following statements about ATP and ADP is TRUE? Select one: a. ATP acts as an allosteric activator of many enzymes in catabolic pathways while ADP acts as an allosteric inhibitor of many enzymes in catabolic pathways. b. ATP and ADP act as allosteric inhibitors of many enzymes in anabolic pathways. c. ATP acts as an allosteric inhibitor of many enzymes in catabolic pathways while ADP acts as an allosteric activator of many enzymes in catabolic pathways. d. ATP acts as an allosteric inhibitor of many enzymes in anabolic pathways while ADP acts as an allosteric activator of many enzymes in anabolic pathways.

C

Which of the following statements about membrane synthesis is TRUE? Select one: a. Both membrane proteins and phospholipids for membranes are synthesized in the smooth ER. b. Membrane proteins are synthesized in the smooth ER but phospholipids for membranes are synthesized in the rough ER. c. Membrane proteins are synthesized in the rough ER and membrane lipids are synthesized in both the smooth and rough ER. d. Membrane proteins are synthesized in the rough ER and phospholipids for membranes are synthesized in the Golgi apparatus.

C

Which of the following statements about protein structure is most accurate? Select one: a. Secondary structure is determined by interactions between amino acid side chains and tertiary structure is determined by interactions between the repeating constituents of the polypeptide backbone. b. Secondary and tertiary structures are determined by interactions between amino acid side chains. c. Secondary structure is determined by interactions between the repeating constituents of the polypeptide backbone and tertiary structure is determined by interactions between amino acid side chains. d. Secondary and tertiary structures are determined by interactions between the repeating constituents of the polypeptide backbone.

C

A major function of the smooth endoplasmic reticulum is the synthesis of Select one: a. protein. b. DNA. c. RNA. d. lipid.

D

Ribosomes consist of Select one: a. RNA and fatty acid. b. DNA and protein. c. phospholipid and protein. d. RNA and protein.

D

The concentration of iodine in the cells of the thyroid gland is many times greater inside the cells than outside them. This situation could be maintained by Select one: a. passive diffusion of iodine across the plasma membrane. b. exocytosis. c. facilitated diffusion of iodine across the plasma membrane. d. active transport of iodine across the plasma membrane. Feedback

D

The molecules shown below are best described as Select one: a. Enantiomers b. Isotopes c. Geometric isomers d. Structural isomers

D

Which structure of the cell is important in movement of organelles, cell shape, and cell motility? Select one: a. cell membrane b. vacuoles c. endomembrane system d. cytoskeleton

D

dentify the asymmetric carbon in this molecule Select one: a. It is the 3rd carbon from the left b. It is the 4th carbon from the left c. It is the 1st carbon on the left d. It is the 2nd carbon from the left

D

ons always diffuse across membranes down their Select one: a. electrochemical gradients b. electrical gradients c. concentration gradients d. chemical gradients

A