Final Bio Exam

Front 1

A normal gene that if mutated can lead to cancer is called a _______.

Back 1

proto-oncogene

Front 2

A gene that causes a cell to become cancerous is called an _______.

Back 2

oncogene

Front 3

A _______ gene is a gene that encodes proteins that inhibit cell division. Such proteins normally help prevent cells from becoming cancerous.

Back 3

tumor-suppressor

Front 4

A _______ is a protein that promotes cell division. In excess, such a protein may lead to cancer.

Back 4

growth factor

Front 5

A gene that can cause cancer when present in a single copy in a cell is called an __________.

Back 5

ocogene

Front 6

Signal transduction pathways _________________________________________________.

Back 6

are mechanisms of communication that probably evolved in ancient prokaryotes.

Front 7

A homeotic gene ___________________________________________.

Back 7

serves as a master control gene that functions during embryonic development by controlling the developmental fate of groups of cells.

Front 8

Enhancers are ____________________________________.

Back 8

DNA sequences to which activator proteins bind.

Front 9

The development of colon cancer occurs slowly, and colon cancer is more frequently seen in the elderly than the young. This is most likely because _______________________________.

Back 9

four or more somatic mutations must occur to give rise to the cancer, which takes time.

Front 10

Mutations in the proto-oncogene ras and the tumor suppressor gene p53 _________________.

Back 10

disrupt normal regulation of the cell cycle.

Front 11

Small pieces of RNA that can regulate translation of mRNA are called _______.

Back 11

microRNA

Front 12

Which of the following mammals has not yet been cloned and brought through the complete gestation cycle?

Back 12

human

Front 13

The carcinogen known to cause the most cases and types of cancer is _______.

Back 13

tobacco

Front 14

A similar protein is found in both a bacterial cell and a single-celled eukaryote. However, the prokaryote seems to produce a much higher amount of the protein. A detailed investigation of the control mechanisms of this protein in both organisms would include which of the following?

Back 14

the mechanisms of transcriptional control

Front 15

The cloning of Dolly the sheep ___________________________________.

Back 15

demonstrated that the nuclei from differentiated mammalian cells can retain their full genetic potential.

Front 16

Alternative RNA splicing has revealed inaccuracies in the one gene - one polypeptide hypothesis. Why?

Back 16

Transcription of the same gene can lead to the production of different mRNAs.

Front 17

Adult stem cells have limited therapeutic potential _________________________________.

Back 17

because their developmental potential is limited to certain tissues.

Front 18

To initiate a signal transduction pathway, a signal binds to a receptor protein usually located in the _____________.

Back 18

plasma membrane

Front 19

The lac operon of E. coli is ________ when the repressor is bound to lactose.

Back 19

active

Front 20

In female mammals, the inactive X chromosome in each cell _______________.

Back 20

becomes a Barr body.

Front 21

After translation is complete, the insulin polypeptide is activated by _____.

Back 21

the cutting of the initial translation product to yield two shorter chains joined together by sulfur linkages

Front 22

The coding regions of a gene (the portions that are expressed as polypeptide sequences) are called
_______.

Back 22

exons