Micro Chapter 8

Question 1

What is a polynucleotide?

Answer 1

multiple nucleotides twisted together

Question 2

How many hydrogen bonds are there between A and T?

Answer 2

two

Question 3

How many hydrogen bonds are there between G and C?

Answer 3

three

Question 4

What is the purpose of hydrogen bonds?

Answer 4

provide stable

structure

Question 5

What is a gene?

Answer 5

• segment of DNA

- functional product

Question 6

What is the purpose of the Antiparallel nature of DNA?

Answer 6

• allows bases to be close to each other

Question 7

What does DNA Helicase do?

Answer 7

• enzyme

- “unzips” DNA for replication

Question 8

What is DNA Gyrase?

Answer 8

• stabilizes the helix

Question 9

Describe replication of the leading strand

Answer 9

• uses DNA polymerase

- results in 5’–>3’ old strand and 3’–>5’ new strand

Question 10

Describe replication of the lagging strand

Answer 10

• RNA polymerase acts as primer
• DNA polymerase adds new nucleotides in short fragments (Okazaki segments)
• DNA ligase seals the gap

Question 11

Describe how replication is different in bacteria cells

Answer 11

• only one strand of DNA
• DNA is circular
• has origin of replication and replication termination point

Question 12

What is the difference between transcription and replication?

Answer 12

• Transcription is the replication of DNA that results in RNA
• only results in one strand because RNA is single stranded

Question 13

Describe Eukaryote RNA splicing

Answer 13

• removal of introns and joining of exons in eukaryotic mRNA, tRNA or rRNA
• accomplished with the help of spliceosomes, which remove introns from the genes in RNA

Question 14

What is a splicosome composed of?

Answer 14

-a mixture of protein and small RNA molecules.

Question 15

How does Leukemia effect transcription?

Answer 15

• causes short interfering RNA to combine with mRNA and a polymer which causes cell death
• cell too mutated with these genes

Question 16

Describe Translation

Answer 16

• tRNA’s anticodon matches with mRNA’s start codon
• more tRNA come and bond to the following chain in the sequence and as they do so their matching amino acids join to the previous amino acid (MET) forming a polypeptide chain

Question 17

Describe the structure of tRNA

Answer 17

• one end has an amino acid (usually MET) and the other has an anticodon (usually UAC)
• the ends always “match” each other ie. each amino acid always has the same anticodon matched to it

Question 18

What is the difference between a prokaryotic genome and a eukaryotic genome?

Answer 18

-prokaryotic- genetic material floats free in cell, mostly coding DNA, double stranded circular DNA called plasmids