Genomic DNA and Nucleic Acids

Question 1

Euchromatin

Answer 1

light staining
gene-rich
actively expressed
open

Question 2

Heterochromatin

Answer 2

dark staining
gene-poor
compacted

Question 3

Methylation

Answer 3

Turns off genes. 70% of CpG pairs are methylated (CG pairs next to each other on same strand)
Causes chromatin to condense
“irreversible” long-term change

Question 4

Histone H1

Answer 4

linker Histone, assists in higher order packaging

Question 5

What charge do Histone Proteins have

Answer 5

Basic. Cuz of basic amino acid histone tails. Lysine residues are acetylated to loosen Heterochromatin to Euchromatin

Question 6

HAT

Answer 6

Histone Acetyltransferase. Add acetyl group to Lysine to loosen Euchromatin

Question 7

LINES

Answer 7

Long Interspersed Nucleotide Elements
-Type of Interspersed Repetitive Repeats
20% of Human Genome
-Transposon that moves through RNA intermediate
-6000 nt long

Question 8

SINES

Answer 8

Short Interspersed Nuclear Elements
Type of Interspersed Repetitive Repeats
13%
AKA Alu repeats. 
inactive
280 nt long

Question 9

Retrovirus like elements

Answer 9

Type of Interspersed Repetitive Repeats

• 8%
• inactive
• Loooong terminal repeats end units
• 1.5-11 kBP long

Question 10

DNA Transposon Fossils

Answer 10

-inactive
3%
80-3000 bp

Question 11

Satellite DNA

Answer 11

Type of Tandem Repeat DNA
AKA alpha DNA
makes centromere
171 BP
3-5%

Question 12

Minisatellite DNA

Answer 12

Type of Tandem Repeat

1. variable nucleotide repeats are used for fingerprinting. Multiple alleles of each locus, based on copy #
2. Telomeric DNA

Question 13

Microsatellite DNA

Answer 13

Type of Tandem Repeat
clusters are shorter
repeat 13 bp or less
also used in DNA fingerprinting

Question 14

How are Transposons involved in Gene Regulation?

Answer 14

“juping genes” help facilitate evolution via mutation but also causes disease.
These recombination events lead to turning on or off genes