Exam 4

Question 1

True multicellularity is a major characteristic of

Answer 1

Eukaryotes only

Question 2

A mutation in the gene encoding the integrase enzyme renders the protein non-functional. How would this affect the HIV infection cycle

Answer 2

The viral DNA would not be able to integrate the viral genome into a chromosome

Question 3

What best describes whether a virus is likely to infect a particular cell?

Answer 3

A virus will only infect host cells with the correct surface receptors

Question 4

Can a virus be killed?

Answer 4

No, viruses are non-living and cannot die

Question 5

A doctor’s office has run out of the latest flu vaccine, but many patients are asking for it. One of the nurses finds some vials from last year’s batch in a refrigerator. Should they be used?

Answer 5

No, because each year the vaccine is made against different subtypes of the flu virus

Question 6

Gardasil is marketed as a cervical cancer vaccine, but it is actually a human papilloma virus (HPV) vaccine. Why is this done

Answer 6

HPV in the cervical epithelial cells may cause the cells to become cancerous

Question 7

Viruses are characterized by all of the following except

Answer 7

Being capable of independent reproduction

Question 8

A layer of lipoprotein and glycoprotein that covers the outer surface of some viruses is the

Answer 8

Envelope

Question 9

Prions are

Answer 9

Infectious proteins with no associated nucleic acid

Question 10

The onset of AIDS is often accompanied by

Answer 10

A steep drop in T cell numbers

Question 11

A scientist is studying the lysogenic cycle of the lambda 1 phage of Escherichia coli. This means that she is investigating

Answer 11

The integration and stabilizing of the lambda 1 phase into a host cell’s genome

Question 12

Viruses infect every organism that has been investigated for their presence. However, viruses can only replicate in

Answer 12

A very limited number of the host’s cells

Question 13

Which of the following is unique feature of viruses that separates them from bacteria?

Answer 13

They are generally smaller

Question 14

Which of the following statements about the types and subtypes of the influenza (flu) virus is false?

Answer 14

Genetic recombination between influenza and other types of viruses is common

Question 15

A fertilized egg is called

Answer 15

Zygote

Question 16

A zygote is a fertilized egg formed by an egg and a sperm. The zygote undergoes many mitotic events as it develops into a solid ball of cells (ie, blastomeres) called a blastula. What changes occur in this early cleavage?

Answer 16

During the initial stages of cleavage, there is a tremendous increase in the number of cells coupled with a decrease in the size of the cells composing the developing organism

Question 17

Cells that can express all of their genes very early in development, each cell is capable of expressing all its genes. This referred to as

Answer 17

Totipotency

Question 18

Scientists attempted for many years to conduct nuclear transplants but failed. However, geneticists had success in cloning a sheep. They were successful because they

Answer 18

Picked a cell very early in development

Question 19

Cells that are programmed to die, shrivel and shrink in a process called

Answer 19

Apoptosis

Question 20

Caenorhabditis elegans is an organism with exactly 959 somatic cells. This organism is

Answer 20

Nematode

Question 21

Egg cells were combined with this cell type to form the cloned sheep named dolly

Answer 21

Mammary cells

Question 22

A complete cell lineage map exists for

Answer 22

C. elegans

Question 23

What was the most significant research finding that resulted from the successful cloning of Dolly?

Answer 23

The nucleus of a fully-differentiated cell can be reprogrammed to be totipotent

Question 24

The main difference between therapeutic cloning and reproductive cloning is that

Answer 24

In therapeutic cloning, embryonic stem cells are extracted from the blastocyst, while in reproductive

Question 25

Cells differentiate through

Answer 25

Gene regulation

Question 26

Multipotent cells of the mesoderm can

Answer 26

Give rise to any cell type of mesodermal origin

Question 27

Which cells, or cell types, has the greatest developmental potential

Answer 27

Fertilized egg

Question 28

Humans with hypohidrotic ectodermal dysplasia have defects in the formation and function of their sweat glands. Males with the condition have reduced ability to sweat over their entire body. Females with the condition lose the ability to sweat only in patches of skin. Where must the gene that encodes this trait be located?

Answer 28

In the X chromosome

Question 29

Alternative splicing may be considered a mechanism of gene regulation because it

Answer 29

Results in different protein products

Question 30

The human body contains approximately 200 major cell types. They look and function differently from one another because each

Answer 30

Expresses a different set of genes

Question 31

Methylation, acetylation, and other histone modifications are important because they are associated with

Answer 31

Chromatin remodeling and thereby affect gene transcription

Question 32

Adding or removing the 5’ cap on messenger RNA helps regulate gene activity at the level of translation because the 5’ is necessary for

Answer 32

Translational initiation

Question 33

You know that Gip1 is only expressed in adult liver cells and not in the liver of embryos. You also know that Jk8 and Pa5 behave similarly on other promoters in the embryo or in the adult, in terms of whether they act as repressors or gene activators. Given the data use of which of the following mechanisms would make the most sense for regulating the Jk8 and Pa5 proteins

Answer 33

Pa5 binds to the promoter of the gene that encodes Jk8 in embryonic liver cells