Chapter 5.5, 16.1, 16.3 - Nucleic Acid

Question 1

Two types of nucleic acid

Answer 1

1. Deoxyribonucleic Acid (DNA)

2. Ribonucleic Acid (RNA)

Question 2

Function of DNA (2)

Answer 2

1. Storage and hereditary information

2. Blueprints for synthesis of proteins

Question 3

Function of RNA (3)

Answer 3

1. Helps regulate protein synthesis
2. Participants directly in protein synthesis
3. Transmits the instructions for making specific proteins

Question 4

DNA in prokaryotes (5)

Answer 4

1. Usually one large circular DNA molecule (chromosome)
2. Can be several smaller circular DNA molecules (plasmids)
3. DNA is not enclosed in the membrane
4. Associated with proteins
5. Condensed (super coiled) into a nucleotide

Question 5

DNA in eukaryotic cells (3)

Answer 5

1. Nucleus
2. Mitochondria
3. Chloroplasts

Question 6

Structure of Nucleic Acid

Answer 6

Monomers = nucleotides

see drawing in notes

Question 7

Structure of Nucleotides (2)

Answer 7

1. Phosphate attaches to 5’ carbon on sugar
2. OH Groups on 3’ carbon required for polymerization of nucleotides

*notes! (Important points from lecture)

Question 8

Nucleic Acids (4)

Answer 8

1. Polymers of nucleotides
2. Polymerization = dehydration reaction
3. Nucleic Acid polymer has directionality 5’3’

*notes and slides

Question 9

Structure of Nucleic Acid and DNA

Answer 9

SEE NOTES:)

Question 10

Complementary base pairing

Answer 10

1. Nitrogenous bases pair with each other and are held together by hydrogen bonds
2. A with T (pyrimidines)
3. G with C (purines)

Question 11

Structure of RNA (3)

Answer 11

1. RNA is a single stranded polymer
2. Has secondary structure due to intrastrand complementary base pairing
3. Transfer RNA and Ribosomal RNA

Question 12

DNA as Genetic Material (3)

Answer 12

1. Structure of DNA is important for transmitting genetic info when cells reproduce
2. Linear sequence of nucleotides is passed to new cells and form parent offspring
3. Each strand serves as a template to order nucleotides in new complementary strands

Question 13

Genes (5)

Answer 13

1. Discrete units of hereditary information
2. Are specific segments of DNA
3. Are specific linear sequences of nucleotides in DNA
4. Occupy distinct regions of chromosome
5. Provide instructions for making specific proteins

Question 14

Packaging of DNA in Nucleus (4)

Answer 14

1. Histone proteins bind to DNA via positively charged amino acids e.g. chromatin
2. DNA wound around histones (nucleosome)
3. Interactions between nucleosomes (chromatic coiled into fibers)
4. Looping of fibers further condensed into chromosomes

SEE SLIDES

Question 15

Heterochromatin

Answer 15

1. Inactive

2. Some regions are packed tightly

Question 16

Euchromatin

Answer 16

1. Active

2. Some regions are less compacted

Question 17

Histones

Answer 17

Proteins responsible for the first level of DNA packing in chromatin