Chapter 11 Flashcards Preview

PCC Biology > Chapter 11 > Flashcards

Flashcards in Chapter 11 Deck (28):
1

Activators

A protein that switches on a gene or group of genes by binding to DNA.

2

Adult Stem Cells

A cell present in adult tissues that generated replacements for nondividing differentiated cells.

3

Alternative RNA splicing

A type of regulation at the RNA-processing level in which different mRNA molecules are produced from the same primary transcript, depending on which RNA segments are treated as exons and which as introns.

4

Carcinogens

A cancer-causing agent, either high energy radiation or a chemical.

5

Cellular Differentiation

Specialization in the structure and function of cells that occurs during the development of an organism; results from selective activation and deactivation of the cells' genes.

6

Complementary DNA (cDNA)

A DNA molecule made in vitro using mRNA as a template and the enzyme reverse transcriptase.

7

DNA microarray

A glass slide containing thousands of different kinds of single-stranded DNA fragments arranged in an array. Tiny amounts of DNA fragments, representing different genes, are attached to the glass slide. These fragments are tested for hybridization with various samples of cDNA molecules, thereby measuring the expression of thousands of genes at one time.

8

Silencers

A eukaryotic DNA sequence that inhibits the start of gene transcription.

9

Therapeutic Cloning

The cloning of human cells by nuclear transplantation of therapeutic purposes, such as the replacement of body cells that have been irreversibly damaged by disease or injury.

10

Operator

In prokaryotic DNA, a sequence of nucleotides near the start of an operon to which an active repressor can attach. The binding of the repressor prevents RNA polymerase from attaching the promoter and transcribing the genes of the operon.

11

Operon

A unit of genetic regulation common in prokaryotes ; a cluster of genes with related functions along with the promoter and operator that control their transcription

12

Promoter

A specific nucleotide sequence in DNA, located at the start of the gene, that is the binding site for RNA polymerase and the place where transcription begins

13

Proto-oncogene

A normal gene that can be converted to a cancer causing gene

14

Regeneration

The regrowth of body parts from part of an organism

15

Repressor

A protein that blocks the transcription of a gene or operon

16

Reproductive Cloning

Using a somatic cell from a multicellular organism to make one or more genetically identical individuals

17

Signal Transduction Pathway

A series of molecular changes that convert a sign on the surface of a target cell to a specific response on the interior of the cell

18

X Chromosome Inactivation

In female mammals, the Inactivation one of the X chromosome in each somatic cell. Once X Inactivation occurs in a given cell, all decedents of that cell will have the same copy of the X chromosome inactivated. (inactivation of an unexpressed gene)

19

embryonic stem cells(ES Cells)

any of the cells in the early animal embryo that differentiate during development to give rise to all the kinds of specialized cells in the body

20

Enhancers

a eukaryotic cell DNA sequence that helps stimulate transcription of a gene some distance from it. An enhancer functions by means of a transcription factor called an activator, which binds to it and the rest of the transcription apparatus.

21

gene expression

the process whereby genetic information flow from genes to proteins, the flow of genetic information from genotype to phenotype: DNA to RNA to Protein

22

gene regulation

the turning off and on of specific genes within a living organism

23

growth factors

a protein secreted by certain body cells that stimulates other cells to divide

24

homeotic genes

a master control gene that determines the identity of a body structure of a developing organism, presumably by controlling the developmental fate of groups of cells. (In plants such genes are called organ identity genes

25

nuclear transplantation

a technique in which the nucleus of one cell is placed into another cell that already has a nucleus or which the nucleus had previously been destroyed. the cell is then stimulated to grow, producing an embryo that is a genetic copy of the nucleus donor

26

oncogene

a cancer causing gene, usually contributes to malignancy by abnormally enhancing the amount of activity of a growth factor made by the cell

27

transcription factors

in eukaryotic cell, a protein that functions in initiating or regulating transcription. Transcription factors bind to DNA or other proteins that bind DNA

28

tumor-suppressor genes

a gene whose product inhibits cell division, thereby preventing uncontrolled cell growth