Test 3A Flashcards
- Which of the following is most true of mitochondria?
a. They produce most of the ATP derived from the breakdown of carbohydrates and fatty acid
b. They produce most of the ATP derived from the breakdown of carbohydrates
c. They produce about half of the ATP derived from the breakdown of carbohydrates
d. They produce about 10% of the ATP derived from the breakdown of carbohydrates
a. They produce most of the ATP derived from the breakdown of carbohydrates and fatty acid
- Actin exists in cells in two major forms called
a. Monomers and dimers
b. A-actin and B-actin
c. G actin and D actin
d. G actin and F actin
e. Actin 1 and actin 2
d. G actin and F actin
- Each monomer of actin binds one molecule of the nucleotide triphosphate
a. ATP
b. GTP
c. CTP
d. UTP
a. ATP
- Which nucleotide triphosphate is hydrolyzed during a cycle of microtubule assembly and disassembly?
a. ATP
b. TTP
c. CTP
d. GTP
d. GTP
- Mitochondrial and chloroplast proteins are synthesized on
a. ER ribosomes
b. free cytosolic ribosomes
c. organellar ribosomes
d. Both b and c
b. free cytosolic ribosomes
- Which of the following contain their own genomes?
a. Mitochondria, but not chloroplasts and peroxisomes
b. Chloroplasts, but not mitochondria and peroxisomes
c. Mitochondria and chloroplasts, but not peroxisomes
d. Mitochondria, chloroplasts, and peroxisomes
c. Mitochondria and chloroplasts, but not peroxisomes
- The infoldings of the inner mitochondrial membrane are called
a. Cisternae
b. Cristae
c. Laminae
d. lacunae.
b. Cristae
- The inner compartment of mitochondria is called the
a. Stroma
b. intermembrane space
c. inner membrane space
d. matrix.
d. matrix.
- What product of glycolysis is transported into the mitochondria?
a. Acetate as acetyl CoA
b. Pyruvate
c. Ethanol
d. Lactic acid
b. Pyruvate
- The citric acid cycle consists of the incorporation of _______ and its oxidation to produce _______.
a. pyruvate; CO2, NADH, and FADH2
b. acetate from acetyl CoA; CO2, NADH, and FADH2
c. pyruvate; CO2
d. acetate; CO2
b. acetate from acetyl CoA; CO2, NADH, and FADH2
- Most small molecules are permeable across
a. both mitochondrial membranes
b. the inner, but not the outer, mitochondrial membrane
c. the outer, but not the inner, mitochondrial membrane
d. neither mitochondrial membrane.
c. the outer, but not the inner, mitochondrial membrane
- The outer mitochondrial membrane contains
a. a lower concentration of proteins than the inner membrane
b. an active transporter for pyruvate
c. proton transporters
d. an active transporter for ATP.
a. a lower concentration of proteins than the inner membrane
- Mitochondria contain
a. no genes of their own
b. genes for mitochondrial proteins
c. genes for mitochondrial proteins and rRNAs
d. genes for mitochondrial proteins, rRNAs, and tRNAs.
d. genes for mitochondrial proteins, rRNAs, and tRNAs.
- The mitochondrial outer membrane contains a channel composed of the protein
a. Claudin
b. Porin
c. Channelin
d. connexin.
b. Porin
- The inner mitochondrial membrane contains proteins that
a. synthesize ATP
b. pump protons
c. transport pyruvate and fatty acids
d. All of the above
d. All of the above
- The process by which mitochondria are thought to have arisen during evolution is called
a. Symbiosis
b. Phagocytosis
c. Endosymbiosis
d. autophagocytosis
c. Endosymbiosis
- The mitochondrial genomes usually consist of
a. a single linear DNA molecule
b. several linear DNA molecules
c. circular DNA molecules
d. None of the above—mitochondria do not have a genome.
c. circular DNA molecules
- The organisms most similar to mitochondria are
a. Progenotes
b. α-proteobacteria
c. cyanobacteria
d. purple sulfur bacteria.
b. α-proteobacteria
- Mitochondrial DNA is inherited by means of
a. Mendelian genetics
b. random assortment
c. paternal transmission
d. maternal transmission.
d. maternal transmission.
- In what way does the mitochondrial genetic code differ from the “universal” genetic code?
a. Some codons code for different amino acids
b. Some codons code for different stop codons
c. The wobble rules are different
d. All of the above
d. All of the above
- Which of the following is a mitochondrial disease?
a. Lou Gehrig’s disease
b. Leber’s hereditary optic neuropathy
c. Crohn’s disease
d. I-cell disease
b. Leber’s hereditary optic neuropathy
- Most mitochondrial proteins are synthesized on
a. mitochondrial ribosomes from nuclear mRNAs
b. cytoplasmic ribosomes; they are imported cotranslationally as they are being synthesized
c. cytoplasmic ribosomes; they are imported after they are completely synthesized
d. mitochondrial ribosomes from mitochondrial mRNAs.
c. cytoplasmic ribosomes; they are imported after they are completely synthesized
- Mitochondrial targeting presequences usually consist of a
a. hydrophobic α helix
b. hydrophobic random chain
c. negatively charged α helix
d. positively charged α helix.
d. positively charged α helix.
- Where are most mitochondrial phospholipids synthesized?
a. Mitochondrial inner membrane
b. Mitochondrial matrix
c. ER
d. Golgi apparatus
c. ER