Module 10 - 4

Question 1

What are the primary enzymes for synthesizing nucleic acids?

Answer 1

DNA and RNA polymerases

Question 2

What are the substrates for nucleic acid synthesis?

Answer 2

Nucleotide triphosphates

Question 3

In what direction do all polymerases synthesize nucleic acids?

Answer 3

5’ to 3’

Question 4

Where are incoming residues added during nucleic acid synthesis?

Answer 4

3’ end of the growing strand

Question 5

What is the criteria for selecting incoming residues during nucleic acid synthesis?

Answer 5

Complimentary to the template strand

Question 6

What is Polymerase Chain Reaction (PCR)?

Answer 6

Amplification of short regions of DNA

Question 7

What does PCR take the advantage of?

Answer 7

the ability for each DNA strand to serve as a template for production of a complimentary

Question 8

How is new DNA made through PCR?

Answer 8

Heat stable enzymes

Question 9

What did PCR revolutionize?

Answer 9

Molecular biology, and diagnostics, and forensics

Question 10

DNA in eukaryotes need to be packaged into what?

Answer 10

Higher order structure due to the amount

Question 11

What is the first level of DNA packaging in eukaryotes?

Answer 11

Formation of nucleosomes

Question 12

What are nucleosome beads?

Answer 12

DNA histone complexes on a string of double stranded DNA

Question 13

What are nucleosomes?

Answer 13

structural unit for packaging chromatin; consisting of a DNA strand around a histone core

Question 14

What are histones?

Answer 14

DNA packaging proteins

Question 15

Characteristics of histones?

Answer 15

Highly conserved and positively charged

Question 16

What are the five histone proteins?

Answer 16

H1, H2A, H2B, H3, and H4

Question 17

What is the composition of a nucleosome?

Answer 17

Two molecules of each H2A, H2B, H3, H4 and 146 base pairs of DNA

Question 18

What is the role of H1 in a nucleosome?

Answer 18

Binds the region of linker DNA

Question 19

How are histones modified to regulate their interaction with DNA?

Answer 19

Reversibly modified

Question 20

What is a gene?

Answer 20

Segment of DNA containing information for production of a biological product

Question 21

How can the size of a gene be estimated?

Answer 21

From the size of the corresponding protein

Question 22

What is the relationship between nucleotides, codons, and amino acids?

Answer 22

3 nucleotides = 1 codon = 1 amino acid

Question 23

Where are genes contained?

Answer 23

Within chromosomes

Question 24

How many chromosomes do viruses and bacteria have?

Answer 24

Single chromosome

Question 25

What is the difference between bacterial and eukaryotic genomes?

Answer 25

Bacterial genomes are closed, circular, and have no introns, while eukaryotic genomes are linear, have introns, and are divided among numerous chromosomes.

Question 26

What is a plasmid?

Answer 26

A non-chromosomal DNA that may contain additional genetic information, such as antibiotic resistance.

Question 27

What is the problem with replicating the ends of eukaryotic chromosomes?

Answer 27

Eukaryotic chromosomes are linear and have repeating sequences called telomeres at the ends.

Question 28

What are introns?

Answer 28

Non-coding regions that interrupt genes in eukaryotic genomes.

Question 29

Do all organisms have the same number of chromosomes?

Answer 29

No, different organisms have different numbers of chromosomes.

Question 30

What is the difference in size between bacterial and eukaryotic genomes?

Answer 30

Bacterial genomes have millions of base pairs, while eukaryotic genomes have billions of nucleotides.

Question 31

What is the difference in chromosome organization between bacterial and eukaryotic genomes?

Answer 31

Eukaryotic chromosomes are organized and have a characteristic set of genes, while bacterial genomes have no internal interruptions.

Question 32

What is the additional DNA found in some organelles?

Answer 32

Mitochondria and chloroplasts may contain additional DNA distinct from that of the nucleus.

Question 33

What is the function of telomeres?

Answer 33

They are repeating sequences at the ends of eukaryotic chromosomes that protect against the loss of genetic information during replication.