Bio 181 Lecture Final Exam.

Front 1

the formation of the fertilization membrane requires an increase in the availability of:

Back 1

Calcium Ions

Front 2

Which of the following genes map out the basic subdivisions along the anterior-posterior axis of the Drosophila embryo?

Back 2

Segmentation genes.

Front 3

The earliest development stage among these choices is:

Back 3

Morula

Front 4

The vegetal pole of the zygote differs from the animal pole in that:

Back 4

The vegetal pole has a higher concentration of yoke.

Front 5

At the time of implantation, the human embryo is called a:

Back 5

Blastocyst.

Front 6

From earliest to latest, the overall sequence of early development proceeds in what sequence?

Back 6

Cleavage-> gastrulation->organogenesis.

Front 7

Two potential devices that eukaryotic cells use to regulate transcription are:

Back 7

DNA methylation and histone modification.

Front 8

During fertilization, the acrosomal contents:

Back 8

Digest the protective jelly coat on the surface of the egg.

Front 9

In animals, embryonic stem cells differ from adult stem cells in that:

Back 9

Embryonic stem cells are totipotent, and adult stem cells are pluripotent.

Front 10

Contact of a sperm with signal molecules in the coat of an egg causes the sperm to undergo:

Back 10

The acrosomal reaction.

Front 11

In all vertebrate animals, development requires:

Back 11

An aqueous environment.

Front 12

For a repressible operon to be transcribed, which of the following must occur?

Back 12

RNA pol must bin to the promoter, and the repressor must be inactive.

Front 13

In eukaryotes, general transcription factors:

Back 13

bind to other proteins or to a sequence element within the promoter called the TATA box.

Front 14

Which of the following experimental procedures is most likely to hasten the mRNA degradation in a eukaryotic cell?

Back 14

Removal of the 5' cap.

Front 15

The cancer-causing forms of the Ras protein are involved in which of the following processes?

Back 15

Relaying a signal from a growth factor receptor.

Front 16

Cells move to new positions as an embryo establishes its three germ tissue layers during:

Back 16

Gastrulation.

Front 17

The tryptophan operon is a repressible operon that is:

Back 17

Turned off whenever tryptophan is added to the growth medium.

Front 18

In placental mammals, the yolk sac:

Back 18

Produces blood cells that then migrate into the embryo.

Front 19

A human blastomere is:

Back 19

An embryonic cell that is much smaller than the ovum.

Front 20

Allolactase, an isomer of lactose, is formed in small amounts from lactose. An E. coli cell is presented for the first time with the sugar lactose (containing allolactose) as a potential food source. Which of the following occurswhen the lactose enters the cell?

Back 20

Allolactose binds to the repressor protein.

Front 21

In humans,identical t wins are possible because:

Back 21

Early blastomeres can form a complete embryo if isolated.

Front 22

In positive control of several sugar-metabolism-related operons, the catabolite protein (CAP) binds to DNA to stimulate transcription. What causes an increase in active CAP?

Back 22

Decrease in glucose and increase in camp.

Front 23

Gases are exchanged in a mammalian embryo in the:

Back 23

Chorion.

Front 24

One hereditary disease in humans, xeroderma pigmentosum (XP), makes homozygous individuals exceptionally susceptible to UV-induced mutation damage in the cells of exposed tissue, especially skin. Without extraordinary avoidance of sunlight exposure, patients soon succumb to numerous skin cancers. Which of the following best describes this phenomenon?

Back 24

Inherited inability to repair UV-induced mutation.

Front 25

Mutations in which of the following genes lead to transformations in the identity of entire body parts?

Back 25

Homeotic genes.

Front 26

At the moment of sperm penetration, human eggs:

Back 26

Are still surrounded by follicular cells.

Front 27

Genomic imprinting, DNA methylation, and histone acetylation are all examples of:

Back 27

Epigenetic phenomena.

Front 28

Give an example of a protein produced by a regulatory gene.

Back 28

Repressor.

Front 29

In a newly fertilized egg, the vitelline layer:

Back 29

Hardens to form a protective cover.

Front 30

Embryonic lethal mutations result in:

Back 30

Phenotypes that are never born/hatched.

Front 31

A human zygote undergoes its first cell division:

Back 31

24 hours after fertilization.

Front 32

Which of the following, when taken up by the cell, binds to the repressor so that the repressor no longer binds to the operator?

Back 32

Inducer.

Front 33

The outer-to-inner sequence of tissue layers in a post-gastrulation vertebrate embryo is:

Back 33

Ectoderm->mesoderm->endoderm.

Front 34

The lactose operon is likely to be transcribed when:

Back 34

The cyclic AMP and lactose levels are both high within the cell.

Front 35

In mammals, the nuclei resulting from the union of the sperm and the egg are first truly diploid at the end of:

Back 35

Initial cleavage.

Front 36

Fertilization normally:

Back 36

Reinstates diploidy.

Front 37

The product of the bicoid gene in Drosophila provides essential info about:

Back 37

The anterior-posterior axis.

Front 38

What is the correct sequence of developmental milestones?

Back 38

Cleavage-> morula->blastula->cleavage

Front 39

As an embryo develops, new cells are produced as the result of:

Back 39

Cell division.

Front 40

From earliest to latest, the overall sequence of early development proceeds in which of the following sequences?

Back 40

Acrosomal reaction->cortical reaction->synthesis of embryo's DNA begins-> first cell division.

Front 41

The reason for using Taq polymerase for PCR is that:

Back 41

It is heat stable and can withstand the temperature changes of the cycler.

Front 42

Why do RNA viruses appear to have higher rates of mutation?

Back 42

Replication of their genomes does not involve proofreading.

Front 43

Which of the following best describes the complete sequence of steps occurring during every cycle of PCR?1. The primers hybridize to the target DNA. 2. The mixture is heated to a high temperature to denature the double-stranded target DNA.3. Fresh DNA polymerase is added.4. DNA polymerase extends the primers to make a copy of the target DNA.

Back 43

A. 2, 1, 4

Front 44

Why might a laboratory be using dideoxy nucleotides?

Back 44

To sequence a DNA fragment

Front 45

Which of the following statements describes the lysogenic cycle of lambda (λ) phage?

Back 45

The phage genome replicates along with the host genome.

Front 46

Genetically engineered plants:

Back 46

Include a transgenic rice plant that can help prevent vitamin A deficiency.

Front 47

The first cloned cat, called Carbon Copy, was a calico, but she looked significantly different from her female parent. Why?

Back 47

X inactivation in the embryo is random and produces different patterns.

Front 48

Which of the following is least associated with the others?

Back 48

Binary fission

Front 49

How does a bacterial cell protect its own DNA from restriction enzymes?

Back 49

By adding methyl groups to adenines and cytosines

Front 50

Which of the following is characteristic of the lytic cycle?

Back 50

A large number of phages are released at a time.

Front 51

As genetic technology makes testing for a wide variety of genotypes possible, which of the following is likely to be an increasingly troublesome issue?

Back 51

The need to legislate for the protection of the privacy of genetic information.

Front 52

Yeast artificial chromosomes contain which of the following elements?

Back 52

Centromeres, telomeres, and an origin of replication

Front 53

Which of the following describes the transfer of polypeptide sequences to a membrane to analyze gene expression?

Back 53

Western blotting

Front 54

Most human-infecting viruses are maintained in the human population only. However, a zoonosis is a disease that is transmitted from other vertebrates to humans, at least sporadically, without requiring viral mutation. Which of the following is the best example of a zoonosis?

Back 54

Rabies

Front 55

To introduce a particular piece of DNA into an animal cell, such as that of a mouse, you would find more probable success with which of the following methods?

Back 55

Electroporation followed by recombination

Front 56

In a hypothetical situation, the genes for sex pilus construction and for tetracycline resistance are located together on the same plasmid within a particular bacterium. If this bacterium readily performs conjugation involving a copy of this plasmid, then the result should be:

Back 56

The rapid spread of tetracycline resistance to other bacteria in that habitat.

Front 57

DNA microarrays have made a huge impact on genomic studies because they:

Back 57

Allow the expression of many or even all of the genes in the genome to be compared at once.

Front 58

Which of the following accounts for someone who has had a herpesvirus-mediated cold sore or genital sore getting flare-ups for the rest of his or her life?

Back 58

Copies of the herpesvirus genome permanently maintained in host nuclei.

Front 59

Which of the three types of viruses shown below would you expect to include a capsid(s)?

Back 59

all three

Front 60

Which of the three types of viruses shown below would you expect to include glycoproteins?

Back 60

I and II only

Front 61

Which of these statements about prokaryotes is correct?

Back 61

They divide by binary fission, without mitosis or meiosis.

Front 62

Viral genomes vary greatly in size and may include from four genes to several hundred genes. Which of the following viral features is most apt to correlate with the size of the genome?

Back 62

Size and shape of the capsid

Front 63

Which of the following is used to make complementary DNA (cDNA) from RNA?

Back 63

Reverse transcriptase

Front 64

In the figure, when new viruses are being assembled (IV), what mediates the assembly?

Back 64

Nothing; they self-assemble

Front 65

The host range of a virus is determined by:

Back 65

The proteins on its surface and that of the host.

Front 66

The DNA fragments making up a genomic library are generally contained in:

Back 66

BACs

Front 67

The segment of DNA shown in Figure 20.2 has restriction sites I and II, which create restriction fragments A, B, and C. Which of the gels produced by electrophoresis shown below best represents the separation and identity of these fragments?

Back 67

B

Front 68

In 1997, Dolly the sheep was cloned. Which of the following processes was used?

Back 68

Fusion of an adult cell's nucleus with an enucleated sheep egg, followed by incubation in a surrogate.

Front 69

What is the most logical sequence of steps for splicing foreign DNA into a plasmid and inserting the plasmid into a bacterium?I. Transform bacteria with a recombinant DNA molecule.II. Cut the plasmid DNA using restriction enzymes.III. Extract plasmid DNA from bacterial cells.IV. Hydrogen-bond the plasmid DNA to nonplasmid DNA fragments.V. Use ligase to seal plasmid DNA to nonplasmid DNA.

Back 69

III, II, IV, V, I

Front 70

Use Figure 20.1 to answer the following question.Which enzyme was used to produce the molecule in Figure 20.1?

Back 70

A restriction enzyme