Bio 5-8

A polysaccharide you are studying contains unbranched β glucose molecules and cannot be digested by humans. Which polysaccharide are you studying? Select one: a. cellulose b. glycogen c. chitin d. DNA e. starch

A

Cyanide is a cellular poison that binds to at least one enzyme involved in producing ATP. If a cell is exposed to cyanide, most of the cyanide will be found within the Select one: a. mitochondria. b. peroxisomes. c. lysosomes. d. ribosomes.

A

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? Select one: a. competitive inhibition b. allosteric regulation c. noncompetitive inhibition d. denaturation

A

How do living organisms create macromolecules, organelles, cells, tissues, and complex higher-order structures? Select one: a. Living organisms create order locally, but the energy transformations generate waste heat that increases the entropy of the universe. b. The laws of thermodynamics do not apply to living organisms. c. Living organisms create order by recycling and reusing energy from the sun.

A

How might a change of one amino acid at an allosteric site, distant from the active site of an enzyme, alter the substrate binding of an enzyme at the active site? Select one: a. by changing the three-dimensional shape of the enzyme b. by changing the shape of the active site c. by changing the optimum substrate for the enzyme d. by changing the binding site for a competitive inhibitor

A

Which of the following statements is true for all exergonic reactions? Select one: a. The reaction proceeds with a net release of free energy. b. The products have more total energy than the reactants. c. A net input of energy from the surroundings is required for the reactions to proceed. d. All products will be converted to reactants, but no reactants will be converted to products.

A

You would like to lose weight. Which of the following should be your preferred food group? Select one: a. Cellulose and chitin b. Sucrose and starch c. Starch and fructose d. Lactose and triglycerides

A

Movement of solutes against their concentration gradient using a transport protein and ATP

Active Transport

A tripeptide has ________. Select one: a. three amino acids and three peptide bonds b. three amino acids and two peptide bonds c. two amino acids and three peptide bonds d. four amino acids and three peptide bonds

B

If plant cells are grown on media containing radioactively labeled nucleotides for one generation, radioactively labeled macromolecules will be detected in which of the following? Select one: a. only in the nucleus and mitochondria b. in the nucleus, mitochondria, and chloroplasts c. only in the nucleus d. only in the nucleus and chloroplasts

B

Polymers are made of monomer subunits that are joined by what type of bonds? Select one: a. hydrophobic bonds b. covalent bonds c. hydrogen bonds d. ionic bonds

B

What could be the correct path for exocytosis? Select one: a. rough ER, Golgi apparatus, smooth ER, plasma membrane b. rough ER, Golgi apparatus, transport vesicle, plasma membrane c. rough ER, lysosome, Golgi apparatus, smooth ER d. rough ER, Golgi apparatus, lysosome, plasma membrane, transport vesicle e. smooth ER, rough ER, exocytosis, Golgi apparatus

B

Which of the following aspects of enzyme structure is best described by a clasping handshake analogy? Select one: a. the specific manner in which an enzyme interacts with water b. the specific manner in which an enzyme binds substrate c. the specific manner in which an enzyme folds to form secondary and tertiary structures d. the specific manner in which an enzyme is denatured by low pH

B

ou are studying a new type of cell that stores a large amount of energy, which molecule(s) would expect to find for energy storage? Select one: a. protein and carbohydrate b. lipid and carbohydrate c. lipid d. protein e. carbohydrate

B

A cell with a lot of rough endoplasmic reticulum is most likely ________. Select one: a. producing large quantities of carbohydrates to assemble an extensive cell wall matrix b. producing large quantities of proteins in the cytosol/cytoplasm c. producing large quantities of proteins for secretion d. producing large quantities of lipids for new membranes.

C

A freshwater unicellular eukaryote without a cell wall, an hour after being dropped into seawater, will be______. Select one: a. swollen. b. unchanged. c. shrunken.

C

A glycosidic bond is analogous to which of the following in proteins? Select one: a. a disulfide bond b. a β pleated sheet c. a peptide bond d. an amino group

C

A molecule with the chemical formula C6H12O6 is probably a ________. Select one: a. nucleic acid b. protein c. carbohydrate d. lipid

C

Gaucher disease is a common lipid storage disease in humans. It is caused by a deficiency of an enzyme necessary for the breakdown of lipids leading to accumulation of fatty material in organs of the body. How are internal membranes and organelles likely involved in Gaucher disease? Select one: a. The Golgi apparatus produces vesicles with faulty membranes, which fail to be transported to the plasma membrane for secretion. b. The mitochondria are most likely defective and do not produce adequate amounts of ATP needed. c. The lysosomes lack sufficient amounts of enzymes necessary for the metabolism of lipids. d. The rough endoplasmic reticulum contains too many ribosomes, which results in an overproduction of the enzyme involved in lipid breakdown.

C

How does RNA differ from DNA? Select one: a. DNA contains thymine; RNA contains uracil. b. DNA forms double stands; RNA is usually single-stranded. c. all of the answers are correct. d. DNA includes the sugar deoxyribose; RNA contains ribose.

C

Suppose a young boy is always tired and fatigued, suffering from a metabolic disease. Which of the following organelles is most likely malfunctioning in this disease? Select one: a. lysosomes b. Golgi apparatus c. mitochondria d. smooth endoplasmic reticulum

C

The molecular formula for glucose is C6H12O6. What would be the molecular formula for a molecule made by linking two glucose molecules together by a dehydration reaction? Select one: a. C18H36O18 b. C6H10O5 c. C12H22O11 d. C12H24O12

C

What would happen to cytoplasmic enzyme activity inside a cell with a normal cytoplasmic pH of 7.2 if you injected a chemical that would change the pH to 4.0? Select one: a. Enzymes would probably denature. b. Little or no change would occur. c. Enzymes would denature and their function decline. d. Enzymes would start to add ATP to all reactions. e. Enzymatic activity would decline.

C

Which statement about osmosis is correct? Select one: a. If a cell is placed in an isotonic solution, more water will enter the cell than leaves the cell. b. If a solution outside the cell is hypertonic compared to the cytoplasm, water will move into the cell by osmosis. c. The presence of aquaporins (water channels in the membrane) should speed up the process of osmosis. d. Osmosis is the diffusion of water from a region of lower water concentration to a region of higher water concentration.

C

Name one of the macromolecule classes that form: Coils or Helices? ______________________________ Sheets or fibrils? ______________________________

Coils or Helices? __nucleic acid____________________________ Sheets or fibrils? ___carbohydrates?___________________________

A defect in which of the following intercellular junctions would allow partially digested material to leak passively between the cells of the small intestine into the abdominal cavity? Select one: a. gap junctions b. desmosomes c. plasmodesmata d. tight junctions

D

A research team is working on the design of a new drug for the treatment of lung cancer. To be most effective, this drug must specifically enter the cytoplasm of lung cells while not entering the cells of other tissues. Which of the following characteristics would likely enhance the targeting of this drug? Select one: a. specificity of the drug molecule for binding to the extracellular matrix of lung cells b. the relative hydrophobicity of the drug molecule c. phospholipid composition of lung cell plasma membranes d. similarity of the drug molecule to other molecules normally transported into lung cells

D

An animal cell lacking carbohydrates on the external surface of its plasma membrane would likely be unable to: Select one: a. establishing a diffusion barrier to charged molecules b. attaching the plasma membrane to the cytoskeleton c. transporting ions against an electrochemical gradient d. cell-cell recognition

D

If you wanted to design a new industrial catalyst based on something biological, which molecule would you try to copy? Select one: a. fatty acid b. chitin c. lipid d. protein e. DNA

D

Which protein is not likely made at the rough ER? Select one: a. insulin (a secreted protein hormone) b. a digestive enzyme of the gut c. collagen from the extracellular matrix d. a ribosome protein from the nucleolus e. an antibody in the blood

D

Compare DNA and RNA Number of polynucleotide strands in typical structure Nucleotide bases present (1 letter abbreviations are ok) Which sugar is included in the nucleotide in each?

DNA. RNA 2 1 A,C,G,T A,C,G,T,U Deoxyribose Ribose

Movement of solutes down their concentration gradient

Diffusion

Poisons are destroyed in the cell by the removal of hydrogen atoms. Where does this occur? Select one: a. Golgi apparatus b. centriole c. rough ER d. nucleus e. smooth ER

E

Bulk transport of materials INTO the cell via vesicles

Endocytosis

Bulk transport of materials OUT OF the cell via vesicles

Exocytosis

Buffers resist changes in acidity but not in alkalinity. Select one: a. False b. True

False

Cells will take up a net increase of water from the isotonic environment. Select one: a. True b. False

False

DNA in a Prokaryotic cell is found in the nucleolus region. Select one: a. True b. False

False

Endergonic reactions release energy. Select one: a. True b. False

False

If you add H+ or OH- to a buffer solution, the pH will change more than if you add those to non-buffered solution. Select one: True False

False

In terms of thermodynamics, organisms are considered to be closed systems. Select one: a. True b. False

False

Lipids, hydrophilic in nature, can act as energy storage, structure or chemical message in the body. Select one: True False

False

Membranes, made of phospholipid bilayers, form as the hydrophobic head and hydrophilic tail of the component phospholipids interact with water. Select one: True False

False

Saturated fats, usually from animal or synthetic sources, are usually liquid at room temperature. Select one: True False

False

Sulfhydryl, methyl, and phosphate functional groups are all polar side groups. Select one: a. True b. False

False

The diffusion of one solute in a solution will directly impact/affect the diffusion of another solute in that same solution. Select one: a. False b. True

False

The linear sequence of amino acids in proteins is due to hydrogen bonding between the C-C-N peptide backbone. Select one: a. False b. True

False

Tissues are the smallest level within the organization of life that can perform all functions of life. Select one: a. True b. False

False

Movement of water across a membrane through which solutes cannot travel

Osmosis

Movement of solutes down their concentration gradient through a transport protein

Passive Transport

A buffer solution resists changes in pH. Select one: a. False b. True

True

All cells of life contain DNA and are surrounded by a cell membrane. Select one: a. True b. False

True

All viruses have nucleic acids and proteins; some also have lipids surrounding them in an envelope. Select one: a. False b. True

True

Cell membranes are semi-permeable allowing some materials to pass through freely while controlling others. Select one: a. True b. False

True

Chemical equilibrium is defined as forward and reverse reactions proceeding at the same rate. Select one: True False

True

Chemical equilibrium is defined as stable ratios of reactants to products in a reaction. Select one: a. False b. True

True

Coenzymes, organic molecules, binding to an enzyme can increase enzyme function. Select one: a. True b. False

True

Communities are collections of populations. Select one: a. True b. False

True

Energy is held within covalent bonds of compounds. Select one: a. False b. True

True

Hydrogen bonding within a macromolecule helps explains molecular shape. Select one: a. True b. False

True

Molecular folding is partially explained by the interactions of the macromolecule with water. Select one: a. True b. False

True

One enzyme usually only works on a single substrate molecule. Select one: a. True b. False

True

Organelles of the endomembrane system are connected physically, or functionally via vesicles. Select one: a. False b. True

True

Plant cells have both chloroplast and mitochondria. Select one: a. False b. True

True

Plants can digest starch. Select one: True False

True

Plasmodesmata and gap junctions connect the cytoplasms of adjacent cells and allow small molecules to pass through. Select one: a. False b. True

True

Polymer folding is partially explained by the interactions of the molecule with water. Select one: True False

True

Prokaryotic and Eukaryotic cells have ribosomes. Select one: a. False b. True

True

The primary structure of a polypeptide is determined by the organism's genes. Select one: a. False b. True

True

The primary structure of proteins is determined by the organism's genes. Select one: True False

True

Water is hydrophilic. Select one: a. False b. True

True