Genomes And Chromosomes

Question 1

When was the human genome completely sequenced?

Answer 1

March 2022, it took so long because the repetitive areas were usually skipped

Question 2

What makes up 1 standard cell?

Answer 2

1 standard cell= 2 genomes= 6 billion base paired=46 chromosomes

Question 3

What percent of the genome encodes protein?
What makes up the rest of the genome?

Answer 3

1.5% of the genome encodes for protein
50% is repetitive and the other 50% is unique

Question 4

What is the repeated sequences of Genome?

Answer 4

Segment duplications
Simple repeats DNA only transposon
Retro Transposon (gets made into RNA)
SINEs (short intersperse nuclear elements) <500
LINEs (long intersperse nuclear elements)>500

Question 5

What is in the unique sequence of genome

Answer 5

Non repetitive DNA that is neither introns nor exons (promoters)
Protein encoded exons
Intros

Question 6

Hybridization- FISH

Answer 6

Diagnostic technique to detect if specific sequences are present

1. Probe DNA
2. Label with fluorescent
3. heat and separate

Question 7

Chromatin

Answer 7

Single, long, linear DNA molecule in a chromosome

Question 8

Levels of chromatin organization

Answer 8

Double helix
Beads-on-a string forms of chromatin (the beads are core histones with red dna strings)
Chromatin fibre of packed nucleosomes
Chromatin fibre folded into loops with help of non-his tone clamp
Entire chromatin

Question 9

Structure of nucleosome

Answer 9

They are made of 4 core histones which are small proteins rich in lysine and arginine.
The core proteins are 2H2A, H2B, H3, H4

Question 10

What is the difference between heterochromatic and Euchromatin

Answer 10

Heterochromatic regions are areas where gene expression is suppressed (Barr body)
Euchromatic regions are where genes are expressed