Exam 2 Test Questions Flashcards
From the list below which functional group is the most oxidized? A. hydroxyl B. carboxyl C. methyl/methylene D. carbonyl E. carbon-carbon double bond
B. carboxyl
Consider the compound below:
O
||
H3C — C —-OH
Which of the following statement(s) is(are) true?
I. This compound has polar and nonpolar groups
II. This compound will donate hydrogen bonds, but cannot accept them
III. This compound will accept hydrogen bonds, but cannot donate them
A. only I is true
B. only II is true
C. only III is true
D. I and II are true
E. I, II, and III are true
A. only I is true
The major organic base in this course A. has a positive charge at high pH B. has a positive charge at low pH C. is the amino group D. A and B E. B and C
E. B and C
All amino acids
A. contain a constant backbone and a nonpolar side chain
B. contain a variable backbone and a constant side chain
C. contain an amino group, a central carbon, and a carboxyl(ic acid) group
D. have acidic or basic side chains
E. have the side chain covalently bonded directly to the carbon atom of the carboxylic acid group
C. contain an amino group, a central carbon, and a carboxyl(ic acid) group
Which of the following is an example of an oxidation reaction?
A. the conversion of elemental chlorine to chloride ions
B. the conversion of an Fe3+ ion to an Fe2+ ion
C. the conversion of a methyl group (CH3) to a carboxylic acid (COOH) group
D. the conversion of Na+ ions to elemental Na0
E. the conversion of a carboxylic acid (COOH) group to a carbonyl (CO) group
C. the conversion of a methyl group (CH3) to a carboxylic acid (COOH) group
Which of the following is NOT true about the hydrophobic effect?
A. It is responsible for the folding of proteins.
B. It is responsible for the association of phospholipids to form bilayers.
C. It leads to an association between a nonpolar group and another nonpolar group.
D. It forms the little fat globules found in chicken soup.
E. All of the above are true.
E. All of the above are true.
Cells are full of biological polymers because
A. polymers are more stable than the monomers (that is, polymers predominate at equilibrium)
B. cells use energy to synthesize polymers from monomers
C. polymers have a large activation energy barrier to degradation
D. A and B
E. B and C
E. B and C
A solution with an H+ ion concentration of 7 x 10^-7 A. is neutral B. is basic C. has a pH greater than 7 D. has a pH less than 7 E. will donate electrons to amino groups
D. has a pH less than 7
Which of the following is NOT true about complex carbohydrates?
A. they are large polymers of glucose
B. they include the most abundant biological material on earth
C. they are only used for energy storage
D. they include both linear and branched molecules
E. all of above are true
C. they are only used for energy storage
Which of the following is true about the ends of polypeptides and nucleic acids?
A. the ends of a polypeptide are named after the amino and carboxylic acid ends of the amino acid monomers
B. the ends of a nucleic acid are named after the 4’ and 2’ atoms in the ribose/deoxyribose sugar of the nucleotide monomer
C. the sequence of a polypeptide is usually written from the carboxyl (C) to the amino (N) end
D. the sequence of a nucleic acid is usually written from the 3’ to the 5’ end
E. none of the above
A. the ends of a polypeptide are named after the amino and carboxylic acid ends of the amino acid monomers
Two polypeptides have very different sequences; they
A. are the same protein, but from different species (like human vs. pig insulin)
B. are different proteins (like insulin vs. keratin)
C. will both fold with the nonpolar amino acid side chains mostly on the outside of the folded protein
D. A and B
E. A and C
B. are different proteins (like insulin vs. keratin)
Consider the compound below:
O H H H H H H H H H H H H H H H
|| | | | | | | | | | | | | | | |
O-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-CH3
| | | | | | | | | | | | | | |
H H H H H H H H H H H H H H H
Which of the following statements is true?
A. The methyl group on the right end of this compound would donate an H+ at high pH
B. The carboxylic acid group on the left end of this compound would gain an H+ to become electrically neutral at high pH
C. This compound will make ester bonds to glycerol in triglycerides and phospholipids
D. This compound is a cis unsaturated fatty acid
E. This compound is a trans unsaturated fatty acid
C. this compound will make ester bonds to glycerol in triglycerides and phospholipids
If “Small TeChies are pyrates” A. T and C are purines B. T and C are pyrimidines C. T and C are polar D. T base pairs with C E. none of the above
B. T and C are pyrimidines
Which of the following statements about heterochromatin and euchromatin is true?
A. Euchromatin is usually located in the periphery of the nucleus.
B. Heterochromatin has fewer RNA products of transcription than euchromatin.
C. Heterochromatin includes the DNA that is actively being transcribed.
D. Euchromatin appears condensed and dark in the electron microscope.
E. None of the above are true.
B. Heterochromatin has fewer RNA products of transcription than euchromatin.
Prokaryotic cells
A. have cell walls made of peptidoglycan (or pseudopeptidoglycan)
B. live only above ground
C. include only bacteria
D. are minor components of the biosphere
E. are generally large (100 micrometers to 1 millimeter)
A. have cell walls made of peptidoglycan (or pseudopeptidoglycan)
Which of the following statements about ribosomes is true?
A. The sequence of the ribosomal RNA (rRNA) determines the sequence of amino acids in a polypeptide.
B. Ribosomes making proteins for export (secretion) are associated with the membranes of the Golgi complex.
C. The rRNA component catalyzes the formation of peptide bonds in polypeptides.
D. All the ribosomes in the cell are associated with the rough endoplasmic reticulum.
E. The protein component catalyzes the formation of ester bonds in polypeptides.
C. The rRNA component catalyzes the formation of peptide bonds in polypeptides.
Which of the following is NOT true about nuclear pores?
A. They are the site where ribosomes are assembled.
B. They cross through both the inner and outer membrane of the nuclear envelope.
C. They are the site where RNA passes from nucleus to cytoplasm.
D. They contain proteins that regulate traffic between the nucleus and cytoplasm.
E. They are visible in electron micrographs as gaps in the nuclear envelope containing some lightly staining material.
A. They are the site where ribosomes are assembled.
The rough endoplasmic reticulum
A. is continuous with the outer bilayer of the nuclear envelope
B. will be prominent in cells making lots of proteins for secretion, like pancreatic cells and plasma cells
C. is discontinuous with the smooth endoplasmic reticulum
D. A and B
E. A and C
D. A and B
Which of the following is(are) dispersed throughout the volume of the nucleus? A. nuclear lamina B. nucleolus C. nuclear matrix D. A and B E. A and C
C. nuclear matrix
The smooth endoplasmic reticulum
A. consists of a series of interconnected flattened sacs
B. is the site for synthesis of proteins destined for export (secretion)
C. is the site of phospholipid, cholesterol and steroid synthesis
D. A and B
E. B and C
C. is the site of phospholipid, cholesterol and steroid synthesis
Recycling old organelles
A. occurs when a secondary lysosome containing the old organelle fuses with a primary lysosome
B. occurs when an autophagosome containing the old organelle fuses with a primary lysosome
C. is promoted by overeating
D. A and B
E. B and C
B. occurs when an autophagosome containing the old organelle fuses with a primary lysosome
The trans face of the Golgi complex
A. is the entrance door of the Golgi
B. is the site where vesicles containing proteins from the ER enter the Golgi
C. is the side of the Golgi towards the nucleus
D. is the side of the Golgi where secretory and lysosomal vesicles leave
E. none of the above
D. is the side of the Golgi where secretory and lysosomal vesicles leave
The secretory pathway for proteins includes which of the following steps in order:
A. SER, transport vesicle, trans Golgi, cis Golgi, secretory vesicle
B. RER, transport vesicle, cis Golgi, trans Golgi, secretory vesicle
C. RER, transport vesicle, trans Golgi, cis Golgi, secretory vesicle
D. SER, RER, transport vesicle, cis Golgi, trans Golgi, secretory vesicle, lysosome
E. RER, secretory vesicle, trans Golgi, cis Golgi, transport vesicle
B. RER, transport vesicle, cis Golgi, trans Golgi, secretory vesicle
Primary lysosomes
A. Contain hydrolytic enzymes that are best segregated from the rest of the cell
B. Will fuse with exosomes containing particles brought into the cell by exocytosis
C. Bud off from the cis Golgi
D. A and B
E. A and C
A. contain hydrolytic enzymes that are best segregated from the rest of the cell