exam 3 MC bio 151 Flashcards
_______ mediate most of cell’s functions.
A. Carbohydrates
B. DNA
C. Lipids
D. Proteins
E. RNA
D. Proteins
Redox reactions are best defined as gain or loss of
____.
A. Carbon
B. Electrons
C. Hydrogens
D. Oxygen
B. Electrons
A mutant that manages to extract more energy out of
a glucose molecule is likely to ______.
A. Be targeted by other cells
B. Have greater fitness
C. Have chromosomal duplication
D. Have deleterious mutations
E. Gain other mutations
B. Have greater fitness
Phosphorylation changes protein’s ______ and thus
affects function.
A. Activity
B. Binding
C. Conformation
D. Potential energy
E. Specificity
C. Conformation
Energy coupling allows ______ reactions to occur
because they are coupled to ______ reactions.
A. Exergonic; endergonic
B. Endergonic; exergonic
C. Exothermic; endothermic
D. Endothermic; exothermic
E. Exergonic; endothermic
B. Endergonic; exergonic
Allosteric regulators _______.
A. Are structurally similar to the substrate
B. Bind to enzyme’s active site
C. Bind and change the enzyme’s shape
D. Can be converted to noncompetitive inhibitor by
modest changes in the structure
C. Bind and change the enzyme’s shape
Plasmodesmata are specialized ____ .
A. Tight junctions
B. Gap junctions
C. Cadherins
D. Desmosomes
E. Doesn’t need any of them
B. Gap junctions
Which of the following motor proteins is important in
cilia and flagella?
A. Axoneme
B. Dynein
C. Kinesin
D. Myosin
E. Spoke
A. Proteoglycans
B. Dynein
The best example of cells with ____ may be our
intestinal cells (or tissue).
A. Tight junctions
B. Gap junctions
C. Cadherins
D. Desmosomes
E. Doesn’t need any of them
A. Tight junctions
Electron transport chain includes a non-protein
electron carrier called ____.
A. Citrate
B. FMN
C. Fe-S cluster
D. Pheophytin
E. Ubiquinone
E. Ubiquinone
Which of the following term is NOT a cell signaling
method?
A. Cell-cell contact
B. Endocrine
C. Paracrine
D. Muscular
E. Neuronal
D. Muscular
FADH2 transfer electrons to ___, and NADH transfer
electrons to ___
A. Complex I; complex II
B. Complex II; complex I
C. Complex I; complex III
D. Complex I & II; complex III
E. Complex I & III; complex IV
B. Complex II; complex I
The electron transport chain transfers electron from
____.
A. Acetyl CoA to NADH
B. CO2 to ATP
C. FADH2 and NADH to O2
D. FADH2 and NADH to CO2
E. The intermembrane space to the mitochondrial matrix
FADH2 and NADH to O2
Enzymes work by _____.
A. adding energy to a reaction
B. adding a phosphate group to a reactant
C. decreasing the potential energy difference
between reactant and product
D. increasing the potential energy difference
between reactant and product
E. promoting formation of the transition state
E. promoting formation of the transition state
Competitive inhibitors ____.
A. Are structurally similar to the substrate
B. Bind to the active site on an enzyme
C. Bind and distort the enzyme’s shape
D. Can be converted to competitive inhibitor by
modest changes in the structure
B. Bind to the active site on an enzyme
If an enzyme is operating at optimal pH and optimal
temperature, then how can the reaction rate be
further increased?
A. Add more substrate
B. Increase pH
C. Increase temperature
D. All of the above
A. Add more substrate
Which of the following amino acid residues in a
protein cannot be phosphorylated?
A. Serine
B. Threonine
C. Tryptophan
D. Tyrosine
C. Tryptophan
Which of the following is incorrect?
A. Complex sugars are carbohydrates.
B. All carbohydrates have the general formula
Cn(H2O)n.
C. Polysaccharides are polymers of simple sugars.
D. Carbohydrates have the most energy of all
macromolecules.
E. Simple sugars contain only carbon, oxygen, and
hydrogen atoms.
D. Carbohydrates have the most energy of all
macromolecules.
The 10 steps of Glycolysis are nearly identical in all
species. What does this mean for evolution?
A. Glucose can be “deconstructed” in only one way
B. Glucose-metabolism enzymes were “collected”
through symbiosis
C. All species must have originated from one ancestral
cell
D. This is because of convergent evolution
E. This is an example of divergent evolution
C. All species must have originated from one ancestral
cell
Which of the following is false about lysosomes?
Which of the following is false about lysosomes?
A. They contain 40+ enzymes
B. They have a pH = 5
C. They are damaged in Zellweger syndrome
D. They break-down phagocytosed material
E. They break-down damaged organelles
C. They are damaged in Zellweger syndrome
A “three parent” baby has ____.
A. Two eggs + sperm nucleus
B. Two sperm nuclei + egg nucleus
C. A sperm + egg nucleus + egg without a nucleus
D. A woman slept with two different men but does
not know who the father is
C. A sperm + egg nucleus + egg without a nucleus
Nucleolus should contain all of the following except__.
A. DNA
B. RNA
C. Lipids
D. Chromosome parts
E. Ribosomal proteins
C. Lipids
. Which of the following is NOT an intermediate in
glycolysis?
A. Fructose-6-phosphate
B. Fructose-1,6-bisphosphate
C. Ribulose bisphosphate
D. 3-phosphoglycerate
E. Phosphoenolpyruvate
C. Ribulose bisphosphate
- Where is calcium stored?
A. microtubules
B. mitochondria
C. centrioles
D. rough endoplasmic reticulum
E. smooth endoplasmic reticulum
E. smooth endoplasmic reticulum
Which of the following metabolic pathways is central
to cellular metabolism in most cells?
A. The citric acid cycle
B. Glycolysis
C. Electron transport chain
D. Lipid degradation
E. Peptide synthesis
B. Glycolysis
