Biology - Dna

Front 1

In 1952 Alfred Hershey and Martha Chase provided conclusive evidence that DNA is the genetic material by using which of the following experimental methods?

Back 1

Examining T2 bacteriophages

Front 2

A bacteriophage is

Back 2

A virus that attaches to a bacterial cell

Front 3

The DNA molecule is made up of subunits, or building blocks called:

Back 3

Nucleotides

Front 4

Which one of the following represents the correct complementary base pairing pattern in the DNA molecule?

Back 4

A-T, G-C

Front 5

The "backbone" of the DNA molecule is composed of:

Back 5

Sugars, Phosphates, and Deoxyribose

Front 6

The currently accepted model for the mode of replication of the DNA molecule is the _____ model.

Back 6

Semi-conservative

Front 7

The researcher(s) who conducted the experiment that allowed for the discovery of the currently accepted model of replication of the DNA molecule was(were):

Back 7

Matthew Meselson and Franklin Stahl

Front 8

The first step in the replication of the DNA molecule involves:

Back 8

Separating the two helices from each other

Front 9

What factor(s) is(are) responsible for the first step in the replication of the DNA molecule?

Back 9

The enzyme helicase is present

Front 10

Complementary bases in the DNA molecule are joined to each other by:

Back 10

Hydrogen bonds

Front 11

Regions in the DNA molecule where replication begins are called:

Back 11

Origins

Front 12

The region where DNA replication is progressing is called a:

Back 12

Replication fork

Front 13

What is a gene?

Back 13

A gene is a sequence of DNA nucleotides that codes for a specific molecular product.

Front 14

What kinds of molecular products do genes produce?

Back 14

Often the product is a kind of a protein that we call an enzyme.

Front 15

mRNA stands for?

Back 15

Messenger RNA

Front 16

This type of RNA carries the genetic information from the nucleus to the ribosomes.

Back 16

mRNA or messenger RNA

Front 17

rRNA stands for?

Back 17

Ribosomal RNA

Front 18

This type of RNA is the site of protein synthesis and, with specific proteins, makes up the structure of the ribosome.

Back 18

rRNA

Front 19

tRNA stands for?

Back 19

Transfer RNA

Front 20

This type of RNA carries amino acids to the ribosome during the process of protein synthesis.

Back 20

tRNA

Front 21

The genetic experiments of Beadle and Tatum, using the red bread mold Neurospora, demonstrated that

Back 21

Mutations can inhibit the production of specific protein metabolites

Front 22

The molecule that occupies an intermediate role to DNA and protein is

Back 22

RNA

Front 23

The group of three nucleotides in a nucleic acid that specify a certain protein is called a(n)

Back 23

Codon

Front 24

Because all but one of the amino acids (tryptophan) have more than one codon by which they can be specified we say that the genetic code is

Back 24

Degenerate

Front 25

At the start of RNA production an enzyme called _____ attaches to the DNA molecule at a place called the _____.

Back 25

RNA polymerase, promoter region

Front 26

The product of transcription is _____ which then undergoes _____.

Back 26

An RNA transcript, RNA processing

Front 27

The movement of the mRNA molecule through the ribosome is called

Back 27

Translocation

Front 28

What facilitates the removal of the polypeptide chain from the ribosome at the conclusion of translation?

Back 28

An enzyme releasing factor

Front 29

Jacob and Monod conducted experiments on the bacterium E. coli in which they demonstrated that genes could be turned on and off. The model that they proposed to explain this phenomenon is called

Back 29

operon

Front 30

DNA where repressor can bind

Back 30

Operator

Front 31

DNA that codes for enzymes

Back 31

Structural gene

Front 32

DNA where RNA polymerase binds

Back 32

Promoter

Front 33

The trp operon in E. coli is called a(n) _____ because it is normally in the "on" condition in the cell.

Back 33

Repressible operon

Front 34

The lac operon in E. coli is called a(n) _____ because it is normally in the "off" condition in the cell.

Back 34

Inducible operon

Front 35

The term that describes the principle that any cell, under the right conditions, may be induced to perform as any other cell in the body is called

Back 35

Totipotency

Front 36

Regions of DNA that are highly condensed and appear to be relatively inactive are called

Back 36

Heterochromatin

Front 37

A group of histone proteins with their associated DNA is called a(n)

Back 37

Nucleosome

Front 38

Very thick chromosomes that are formed when the chromosome replicates many times without daughter strands separating is called a(n)

Back 38

Polytene chromosome

Front 39

Some cells require the operation of a large number of ribosomes. In order to have a sufficient number of ribosomes present there is a special region of DNA in the nucleus, called the _____, that codes for the production of ribosomes.

Back 39

Nucleolus

Front 40

Proteins that regulate transcription in eukaryotic cells are called

Back 40

Transcription factors

Front 41

Which of the gene control mechanisms is indicated by the following list of terms? Introns, exons, mature mRNA

Back 41

Posttranscriptional control

Front 42

Mature mRNA molecules that remain inactive in the cell until specific conditions appear is an example of

Back 42

Masked mRNA

Front 43

After translation the protein may be modified by specific folding patterns of the polypeptide chain, adding other polypeptide chains to form a complex protein, removal of specific sections of the molecule, or adding specific molecules. This process is called

Back 43

Protein activation

Front 44

Protein degradation is accomplished by

Back 44

Proteasomes

Front 45

A permanent change in the sequences of bases in the DNA molecule is called a(n)

Back 45

Mutation

Front 46

The following is an example of a(n) _____.

THE CAT ATE THE RAT → THE ATA TET HER AT_

Back 46

Frameshift mutation

Front 47

A proto-oncogene is

Back 47

A gene that, if mutated, can lead to cancer

Front 48

Enzymes that cut the DNA molecule at specific nucleotide sequences are called

Back 48

Endonucleases