Chapter 7 (from quizlet)

Question 1

what did the experiment by Fred Griffith in 1928 with the R and S strains of Streptococcus pneumoniae demonstrate?

Answer 1

Genetic material from one strain could be transferred to another strain

Question 2

What did the experiment by Avery, MacLeod, and McCarty in 1944 with the R and S strains of Streptococcus pneumoniae demonstrate?

Answer 2

DNA was the genetic material in cells

Question 3

The Hershey and Chase experiment was able to conclusively demonstrate the DNA (not protein) was the genetic material. They were able to distinguish DNA from protein since labeled___incorporated into DNA while_____ incorporated into proteins.

Answer 3

phosphorous; sulfur

Question 4

The Watson and Crick model showed that in the DNA molecule..

Answer 4

purines paired with pyrimidines and the strands align anti-parallel to one another

Question 5

The Watson-Crick model of DNA shows that the base adenine pairs with what?

Answer 5

thymine while cytosine pairs with guanine

Question 6

What is the main difference between Bacteria and Archae chromosomal DNA when compared to Eukarya chromosomal DNA?

Answer 6

Bacteria and Archaea are cicrular while Eukarya is linear

Question 7

Replication of the bacterial chromosome begins at how many locations?

Answer 7

one

Question 8

Replication termination in E. Coli involves which 2 proteins?

Answer 8

Tus protein and topoisomerase II.

Question 9

What is the term for a special sequence at the end of the chromosome in eukaryal cells?

Answer 9

a telemore

Question 10

A gene can best be described as a segment of DNA that…

Answer 10

is transcribed as well as the associated regulatory regions

Question 11

What are micro RNAs?

Answer 11

small regulatory, RNAs

Question 12

For the initiation of transcription in bacteria, RNA polymerase binds to what region on the gene?

Answer 12

promoter

Question 13

What is the sigma factor of the RNA polymerase holoenzyme responsible for?

Answer 13

recognition of the promoter region

Question 14

Most bacterial promoters consist of what two regions?

Answer 14

pribnow (-10) and -35 region

Question 15

Transcription termination in eukaryal cells is more complex than in bacterial cells as the RNA molecule undergoes further processing before becoming a functional mRna; describe this process

Answer 15

capping the 5’ end with 7-methyl guanosine, adding apoly-A sequence at the 3’ end and removing internal sequences called introns

Question 16

What is a codon?

Answer 16

3 bases on the mRNA that is read by the ribosome in the 5’ to 3’ direction

Question 17

Initiation of translation in bacteria starts with the binding of the 30S ribosomal subunit to the mRNA molecule. The ribosomal binding site nearer the ___end of the mRNA molecule and is called the ___

Answer 17

5’; Shine-Dalgarno sequence

Question 18

The mRNA of bacterial cells is often polycistronic. What is polycistronic?

Answer 18

It contains the code for multiple peptides

- coding for more than one protein

Question 19

What would a signal peptide be used for?

Answer 19

to move protein to the outside of the cell

Question 20

What term is used for a point mutation that results in a change in the amino acid specificity of the codon?

Answer 20

missense

Question 21

What is the point mutation that results in changing a codon from an amino acid codon to a stop codon?

Answer 21

nonsense

Question 22

What results from a deletion of base pairs such that the amino acid sequence is disrupted from the point downward?

Answer 22

frameshift mutation

Question 23

What does Rho-independent termination of transcription in bacteria involve?

Answer 23

the formation of a hairpin loop followed by a poly U sequence

Question 24

Messenger RNA (mRNA) can be best described as a molecule that contains the code for a:

Answer 24

polypeptide

Question 25

What best differentiates DNA and RNA?

Answer 25

RNA is single-stranded and DNA is double stranded, RNA contains ribose and DNA contains deoxyribose, RNA contains the base uracil in place of thymine, which is in DNA

Question 26

What are the main enzymes responsible for replication of DNA in eukaryal cells?

Answer 26

DNA pol ε and DNA pol δ

Question 27

What is true regarding replication of the bacterial chromosome?

Answer 27

replication occurs in a bidirectional manner from the origin of replication, the primase adds a short RNA primer to serve as a starting point for the DNA polymerase to add to new bases, DNA replication is a semi-conservative process where one strand serves as a template for the synthesis of a complementary strand, the incoming nucleotide triphosphate is covalently attached to the free 3’ hydroxyl