Bio Exam Questions

Front 1

What functional group is polar and can act as a weak acid by donating a proton at neutral pH?

Back 1

Carboxyl group

Front 2

A cell engulfs an organism, enclosing it in a vesicle. The organism is partially digested in that vesicle. The cell then expels the indigestible waste through the membrane. The cell is using:

Back 2

phagocytosis followed by exocytosis

Front 3

During what stage of cellular respiration is the most ATP synthesized?

Back 3

The electron transport chain and chemiosmosis

Front 4

What type of organelle or structure is primarily involved in the synthesis of oils, phospholipids, and steriods?

Back 4

the smooth endoplasmic reticulum

Front 5

The side chain (R group) of the amino acid serine is -CH2-OH. The side chain of the amino acid leucine is -CH2-CH-(CH3)2. Where would you expect to find these amino acids in a globular protein in aqueous solution?

Back 5

Serine would be on the exterior and leucine would be in the interior of the globular protein.

Front 6

Hydrogen bond are formed

Back 6

when hydrogen is part of a polar bond

Front 7

The end product of glycolysis is

Back 7

pyruvate

Front 8

In an energetically closed system at a constant temperature, the reversible reaction xy <->zw occurs. If the free energy of xy = 6 and that of zw = 12, then

Back 8

xy->zw will occur spontaneously

Front 9

What aspect of triglyceride structure accounts for their insolubility in water?

Back 9

The C-H bonds in fatty acids

Front 10

Animals store glucose in the form of

Back 10

glycogen

Front 11

Which of the atoms would be most likely to form a cation with a charge of +1?

Back 11

One with one valence electron

Front 12

How many water molecules would be produced from the dehydration reactions associated with making a protein that has a primary structure consisting of 101 amino acids and a quaternary structure of 2 identical subunits?

Back 12

200

Front 13

During chemiosmosis in aerobic respiration, protons are pumped

Back 13

out of the matrix into the intermembrane space of the mitochondria

Front 14

Which three components are present in AMP?

Back 14

sugar, phosphate group, nitrogenous base

Front 15

Which two functional groups are always found in amino acids?

Back 15

Carboxyl and amino

Front 16

How many high-energy bonds does ATP have?

Back 16

2

Front 17

Which of the following statements about enzyme catalyzed reactions is true?

Back 17

The rate of the reaction is greater than when the same reaction occurs in the absence of an enzyme.

Front 18

A molecule containing carbon and oxygen would

Back 18

be likely to dissolve in water

Front 19

Noncompetitive inhibitors function to

Back 19

alter the shape of an enzyme

Front 20

During facilitated transport, solute is transported across the membrane

Back 20

at a rate that can, sometimes, be limited by the number of carrier proteins present in the membrane

Front 21

Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules?

Back 21

Proteins

Front 22

What substance is regenerated by fermentation?

Back 22

NAD+

Front 23

A transport vesicle containing proteins from the rough endoplasmic reticulum will travel to the

Back 23

cis face of the Golgi apparatus

Front 24

Cells can change their shape by rapidly polymerizing and depolymerizing

Back 24

microtubules and microfilaments

Front 25

The ATP cycle is continuous. Which statement describes it best?

Back 25

ATP hydrolysis is exergonic and is coupled to drive endergonic cellular reactions

Front 26

Hydrophobic interactions occur between

Back 26

methyl groups in two molecules

Front 27

The sodium-potassium pump generates the following concentration gradients across the plasma membrane:

Back 27

low [NA+] and high [K+] inside the cell and high [Na+] and low [K+] outside

Front 28

What variables influence whether a molecule of hydrogen gas can move across a membrane by passive diffusion?

Back 28

The difference in concentration of the molecule across the membrane

Front 29

After electrons are harvested during reactions in the Krebs cycle

Back 29

they are transferred to NAD+

Front 30

Mammalian blood contains the equivalent of 0.15M NaCl. Seawater contains the equivalent of 0.45M NaCl. What will happen if red blood cells are transferred to seawater?

Back 30

Water will leave the cells, causing them to shrivel and collapse.

Front 31

The electrochemical gradient is a form of kinetic energy used by ATP synthase.

Back 31

False

Front 32

The nucleus and mitochondria within a eukaryotic cell are bounded by double membranes.

Back 32

True

Front 33

All proteins have primary, secondary, tertiary, and quaternary levels of protein structure.

Back 33

False

Front 34

Enzymes decrease the activation energy for a reaction which then shifts the relative amount of reactant converted to product.

Back 34

False

Front 35

In coupled transport, one molecule moves across the membrane down its concentration gradient while a different molecule moves up its gradient, such as in the transport of glucose by Na+.

Back 35

True

Front 36

When an intracellular vesicle is formed by receptor-mediated endocytosis, the intracellular vesicle contains a mixture of different types of proteins bound to their receptors as "cargo."

Back 36

False

Front 37

A peptide bond forms when the carboxyl end of one amino acid joins to the carboxyl end of another.

Back 37

False

Front 38

Each element has a different number of protons in the nucleus.

Back 38

True

Front 39

The energy from the hydrolysis of ATP may be directly coupled to endergonic reactions by the transfer of a phosphate group to another molecule.

Back 39

True.

Front 40

In water, phospholipid molecules spontaneously form a bilayer, with phosphate groups facing inward toward the middle of the bilayer and tails facing out away from the the exterior of the bilayer.

Back 40

False

Front 41

As polypeptides are formed at the ribosome, elongation continues until

Back 41

a stop codon is exposed.

Front 42

What would occur if the repressor of an inducible operon were mutated so it could not bind the operator?

Back 42

continuous transcription of the operon's genes

Front 43

The two strands of DNA foundin a double helix are

Back 43

antiparallel.

Front 44

Activation of the MAP kinase cascade

Back 44

amplifies the intracellular signal generated by ligand-receptor binding.

Front 45

What functional group is found at the 5′ end of a DNA strand?

Back 45

A phosphate group

Front 46

During this phase of the cell cycle cells are preparing for DNA synthesis, producing new macromolecules that will be used in this process and assessing the nutritional content of a cell’s surrounding environment

Back 46

G1

Front 47

If you cross a true-breeding dominant plant with a true-breeding recessive plant, what will be the phenotype of the resulting progeny?

Back 47

All dominant

Front 48

How many different gametes can be produced in an individual that is heterozygous for two Mendelian genes?

Back 48

4

Front 49

Blood types in humans is an example of multiple alleles for one gene. In AB blood type, neither allele is dominant. Thisis also an example of

Back 49

codominance

Front 50

Which of the following statements about the replication of DNA is false?

Back 50

New nucleotides are added to the 3 ́ end of one strand and the 5 ́ end of the other strand.

Front 51

A man with normal vision marries a color-blind woman. Red-green color blindness is an X-linked recessive disorder. What proportion of their sons would be color-blind?

Back 51

All.

Front 52

A man with normal vision marries a color-blind woman. Red-green color blindness is an X-linked recessive disorder. They have a daughter who has normal color vision; what is the probability she is heterozygous for this gene?

Back 52

100%

Front 53

Where does transcription take place?

Back 53

In the nucleus

Front 54

Use the provided table of codons to answer this question. A peptide has the sequence NH2-phe-pro-lys-gly-phe-pro-COOH. Which of the following sequences in the coding strand of the DNA could code for this peptide?

Back 54

5'-TTT-CCC-AAA-GGG-TTT-CCC

Front 55

When tryptophan (an amino acid) is present in the external medium, the bacterium brings in the tryptophan and does not need to make this amino acid. Which of the following is true when there is no tryptophan in the medium?

Back 55

The repressor is inactive, and RNA polymerase moves through the operator.

Front 56

What would happen to chromosomes in the absence of telomerase activity?

Back 56

Chromosomes would shorten during each division.

Front 57

Changing the codon AGC to AGA represents a

Back 57

missense mutation

Front 58

How many chromosomes go to each spindle pole during meiosis II in a normal human germ line cell?

Back 58

23

Front 59

Receptor tyrosine kinases are inactivated by

Back 59

dephosphorylation

Front 60

Which of the following is a characteristic or function of the protein encoded by the p53 gene?

Back 60

It is a protein that monitors the integrity of replicated DNA

Front 61

Refer to the drawings in Figure 10.2 of a single pair of homologous chromosomes as they might appear during various stages of mitosis or meiosis. Which diagram represents anaphase II of meiosis?

Back 61

Drawing 5

Front 62

Refer to the drawings in Figure 10.2 of asingle pair of homologous chromosomes as they might appear during various stages of either mitosis or meiosis. Which diagram represents anaphase I of meiosis?

Back 62

Drawing 1

Front 63

If the DNA content of a diploid cell in the G1 phase of the cell cycle is represented by x, then the DNA content of the same cell at metaphase of meiosis II would be

Back 63

x

Front 64

When tryptophan is present in the environment ofE. coli, the tryptophan binds to the

Back 64

trp repressor

Front 65

A homozygous individual for dominant forms of alleles A and B and a heterozygous individual mate. What fraction of the offspring will be heterozygous for A and homozygous for the dominant form of allele B?

Back 65

1/4

Front 66

Different receptors can have the same effect on a cell. One reason for this is that

Back 66

signal transduction pathways intersect: the same pathway can be stimulated by different receptors.

Front 67

Crossing over occurs in

Back 67

prophase I

Front 68

A somatic cell from an organism normally contains 20chromosomes in its nucleus. How many chromosomes go to eachspindle pole during mitosis?

Back 68

20

Front 69

During this checkpoint, the accuracy of DNA replication is assessed:

Back 69

the G2/M checkpoint

Front 70

Hormones tend to bind to

Back 70

Intracellular receptors.

Front 71

What’s the probability that a single offspring of Labrador retriever from two parents (Bbee x BbEe) will be yellow(_ _ ee)?

Back 71

1/2

Front 72

DNA polymerase I, unlike the other DNA polymerases, has exonuclease activity that is essential during lagging strand replication to

Back 72

remove the RNA primers.

Front 73

Use the provided table of codons to answer this question. What amino acid sequence will be produced based on the following mRNA codon sequence? 5'-AUG-UCU-UCG-UUA-UCC-UUG-3'

Back 73

met-ser-ser-leu-ser-leu

Front 74

A part of an mRNA molecule with the following sequence is being read by a ribosome: 5'-CCG-ACG-3' (mRNA). The anticodon of the first tRNA that will complement this mRNA during translation is:

Back 74

3'-GGC-5'

Front 75

Acetylation is themodification of thehistone tails that allows DNA to be accessible for transcription

Back 75

True

Front 76

During interphase each chromosome replicates to produce two sister chromatids.

Back 76

True

Front 77

All DNA polymerases add new bases to the 5' end of existing strands.

Back 77

False

Front 78

After mitosis, two daughter cells have a complete genome that is identical to the original cell.

Back 78

True

Front 79

Somatic and gamete-producing germ-line cells are diploid. Somatic cells undergo meiosis to produce haploid gametes and germ-line cells undergo mitosis to form genetically identical, diploid daughter cells.

Back 79

False

Front 80

In anaphase I, homologous chromosomes are drawn toward opposite poles. In mitotic anaphase, sister chromatids are drawn to opposite poles.

Back 80

True

Front 81

In an inducible operon, the regulatory protein is synthesized in inhibitory form.

Back 81

True

Front 82

All G proteins are active when bound to GTP and inactive when bound to GDP.

Back 82

True

Front 83

A sex linked trait is usually one determined by a gene carried on the Y chromosome.

Back 83

False

Front 84

Transfer RNA has two functional regions, one that is covalently attached to an amino acid, and the other that can base-pair with DNA.

Back 84

False

Front 85

The human genome is completely sequenced and all errors and gaps have been filled in or corrected thanks to the 200+ labs that worked on this effort.

Back 85

False

Front 86

During the latent phase of the HIV virus, the viral DNA becomes integrated into the host chromosome.

Back 86

True

Front 87

A recombinant DNA molecule is one that is constructed form DNA from different sources.

Back 87

True

Front 88

Viruses are alive.

Back 88

False.

Front 89

A cDNA library is a set of clones each transfected with a different fragment of DNA inserted in a plasmid. The set of clones reflects the entire genome.

Back 89

False

Front 90

It is currently illegal for insurance companies and employers to request that individuals undergo genetic testing for screening purposes.

Back 90

True

Front 91

The CRISPR-Cas9 system is a major advance that enables scientists to more precisely edit specific nucleotide sequences within DNA.

Back 91

True

Front 92

Each B cell has more than one type of immunoglobulin on its surface that is capable of binding to more than one type of antigen.

Back 92

False

Front 93

PCR enables the amplification of a piece of DNA without the use of bacterial cloning.

Back 93

True

Front 94

Vaccines rely on the formation of memory cells for their immunoprotective effects.

Back 94

True

Front 95

What are the steps that occur during each cycle of PCR?

Back 95

Denaturation, Primer Annealing, Synthesis

Front 96

In order to clone a gene, a plasmid vector must have

Back 96

An origin of replication, a selectable marker, and one or more unique restriction sites

Front 97

Rejection of transplanted tissue occurs mainly because of recognition by

Back 97

T-Cells

Front 98

When creating a cDNA library, you start by

Back 98

isolating mRNA from a sample of cells.

Front 99

What factor upregulates the proliferation of helper T cells bound to their antigen?

Back 99

the presence of interleukin-2

Front 100

Prior to entry, the glycoprotein ____ of the HIV virus recognizes the ____ receptor on the surface of the macrophage.

Back 100

gp120; CD4+

Front 101

One day, DNA vaccines may provide a stronger immune response than traditional types of vaccines. What is a reason for this?

Back 101

The DNA enters cells and is transcribed and translated to form proteins that ultimately activate cytotoxic T cells of the immune system.

Front 102

The goal of antisense oligonucleotides for gene therapy is to

Back 102

block translation of mRNA into protein

Front 103

A primary difference between the shotgun sequencing approach and the clone by clone approach is

Back 103

the use of a computer algorithm to aid in piecing sequence fragments back together.

Front 104

The genetic nondiscrimination act states that

Back 104

neither employers nor insurance companies are allowed to request genetic testing or information from an individual; insurance companies aren't allowed to refuse coverage based on genetic testing; employers are not allowed to make adverse employment decisions based on genetic testing.

Front 105

Gene therapy treatments for SCID involve isolating a patient's stem cells, introducing the healthy copy of the adenosine deaminase gene, and injecting the fixed cells back into the body. This type of gene therapy is an example of

Back 105

an ex vivo gene therapy approach.

Front 106

Which of the following is a key concern with gene therapies for treating genetic disease?

Back 106

Insertional mutagenesis and tumor formation and immune reactivity.

Front 107

To be activated, T cells must

Back 107

recognize peptide fragments bound to self-MHC proteins.

Front 108

In a DNA microarray, one sample is labeled green and the other red with fluorescent dyes. If the results on a spot are yellow,

Back 108

each sample has the same amount of mRNA for that gene.

Front 109

Opsonization refers to a process in which

Back 109

multiple copies of antibody bind to antigens on a foreign cell, macrophages bind to the tail end of antibodies bound to their antigen, and macrophage phagocytosis is enhanced.

Front 110

The restriction enzyme BgIII has the recognition sequence (A*GATCT). DNA cut by which of the following restriction enzymes could be ligated to a piece of DNA cut with BgIII?

a. HindIII (A*AGCTT)

b. Pvul (CGAT*CG)

c. BamHI (G*GATCC)

d. Xbal (T*CTAGA)

Back 110

BamHI (G*GATCC)

Front 111

Diseases in which the person's immune system no longer recognizes its own MHC proteins as "self" are called

Back 111

autoimmune diseases

Front 112

Some individuals have resistance to HIV due specifically to a mutation of the gene encoding for

Back 112

the CCR5 receptor

Front 113

Different strains of the flu virus differ in which of the following?

Back 113

Envelope proteins

Front 114

MHC type 1 molecules can be found on

Back 114

all body cells.

Front 115

Which of the following characteristics determine a virus' host range?

Back 115

The proteins on its surface and that of the host.

Front 116

What is the correct order of events in a generalized viral replicative cycle?

Back 116

1. The virus enters the cell

2. Host enzymes replicate the viral genome

3. Enzymes transcribe the viral genome into mRNA

Front 117

What is an accurate statement about the human genome project?

Back 117

The importance of this endeavor is said to be on the scale of the development of the periodic table of the elements.

Front 118

The technique used to separate DNA molecules based on their length/mass is called

Back 118

gel electrophoresis

Front 119

AZT inhibits ______ to prevent HIV.

Back 119

reverse transcription of viral RNA

Front 120

The difficulty in designing a single flu vaccine that will work forever is that influenza

Back 120

both mutates and undergoes antigenic shifts to form new viruses.

Front 121

What determines the ability of a cell to act as an antigen presenting cell for helper T cells?

Back 121

The presence of MHC II proteins

Front 122

Insulin has been successfully produced in E. Coli using reombinant DNA techniques. Before they were successful, scientists have had to over come some obstacles associated with producing a human protein in E. Coli. What are stops incorporated in the final approach?

Back 122

Independent production of each insulin subunit in separate populations of bacteria

Removal of all introns from the insulin gene

Fusion of the beta gal gene to the gene for each subunit chain in insulin.

Chemical linkage of the two insulin subunit chains together by a disulfide bond.

Front 123

Describe how antibodies help us fight against foreign invaders?

Back 123

Antibodies can activate the MAC via the complement system, neutralize toxins secreted by bacteria, enhance phagocytosis of foreign invaders by macrophages, and stimulate natural killer cells.