DNA and RNA (Lec 6)

Question 1

Messenger RNA (mRNA)

Answer 1

Synthesized using DNA template as single strand. Contain ribose instead of Deoxyribose. Together with tRNA, transfers genetic information from DNA to proteins

Question 2

Monocistronic

Answer 2

Strand of mRNA with only a single coding gene

Question 3

Polycistronic

Answer 3

Strand of mRNA with multiple coding genes

Question 4

Palindromic Sequences

Answer 4

Allow mRNA to form Cruciforms and Hairpins

Question 5

DNA Denaturing

Answer 5

DNA denatures in pH or temperature that lay outside a specific range. Covalent bonds remain intact, Hydrogen bonds do not, causing separation of DNA strand

Question 6

Annealing

Answer 6

Process of reversing denaturation

Question 7

Denaturation of Large DNA Molecules

Answer 7

Not uniform, because:

• A-T bonds are double bonds (2H), requires more energy to break
• C-G bonds are triple bonds (3H), require less energy to break

Question 8

DNA Replication Properties

Answer 8

3 Fundamental Rules of Replication:

1. Replication is Semi-conservative
2. Replication begins at an origin and continues bi-directionally
3. Synthesis of new DNA occurs in the 5’->3’ direction and is semi-discontinuous

Question 9

DNA Synthesis (5’ and 3’ directions)

Answer 9

Template DNA: 3’ -> 5’

New DNA: 5’ -> 3’

Question 10

DNA Degredation

Answer 10

DNases: degrade DNA
RNases: degrade RNA

Question 11

Exonucleases

Answer 11

Cleave bonds that remove nucleotides from the ends of DNA

Question 12

Endonucleases

Answer 12

Cleave bonds within a DNA sequence