2ry

Question 1

Melting temperature

Answer 1

The temperature that produces loss of 50% of DNA helical form

Question 2

What is the part of DNA that gets transcripted into an rna

Answer 2

Gene (coding DNA)

Question 3

What are the exons and introns

Answer 3

Exons: coding region
Introns:non coding region

Question 4

What is the genome

Answer 4

Total DNA content in the chromosome of a cell

Question 5

Function of the non coding DNA

Answer 5

Contains genes for RNA molecules

Question 6

Haploid human genomes DNA

Answer 6

In germ cells( eggs and sperm)»3m DNAbase

Question 7

Diploid genomes DNA

Answer 7

In somatic cells ( 6m DNAbase)

Question 8

The DNA in prokaryotic cells

Answer 8

One single double stranded supercoiled circular chromosome +plasmids

Question 9

What are the plasmids

Answer 9

Small circular extrachromosomal DNA molecules

Question 10

What does chromatin consist of

Answer 10

1. Very long double stranded DNA molecules
2. Equal mass of histon protiens
3. Small amount of non histone proteins
4. Small quantity of RNA

Question 11

E.g on non histone proteins

Answer 11

Transcriptional factors , polymerases, hormone receptor, nuclear enzymes

Question 12

When we can see chromatin under light microscope

Answer 12

When it’s undergoing meta phase of cell division

Question 13

What is the q arm

Answer 13

Long arm structure

Question 14

What is p arm

Answer 14

Short arm structure

Question 15

Types of chromosome

Answer 15

1. Metacentric
2. Submetacentric
3. Acrocentric
4. Telocentric

Question 16

Histone proteins are rich in what amino Acids

Answer 16

Lysine & arginine

Question 17

From where do DNA gets their negative charge

Answer 17

The presence of phosphate groups

Question 18

Role of histones

Answer 18

1. DNA supercoiling
2. Regulation of gene expression

Question 19

The centromere is rich in what

Answer 19

A-T (easy to break )

Question 20

Centromere is connected to a specific protiens to form what

Answer 20

Kinetochore ( connected to mitotic spindle )

Question 21

Chromatids telomeres are characterized by the presence of what

Answer 21

Specific repeated num of bases sequence (TTAGGG)n

Question 22

Nucleosomes is consist of

Answer 22

DNA wrapped around 8 histones

Question 23

How the DNA is wrapped around histones

Answer 23

Left handed(1.75)turns

Question 24

Linker or spacer DNA function

Answer 24

Connects the different nucleosomes like beads on a string

Question 25

Where H1 histones are connected

Answer 25

On linker DNA

Question 26

First level of supercoiling

Answer 26

Packing ratio of 10>>supercoiling around histones to form nucleosomes (10 nm fibril)

Question 27

Second level of supercoiling

Answer 27

Require H1 histone>>packing ratio of 50 >>solenoid(contains 6 nucleosomes)>>30 nm fiber

Question 28

Third level of supercoiling

Answer 28

Packing ratio of 8000>>30 nm fiber coil into twisted loop >>attached to a protien >>rosettes(contains 6 loops)>>rosettes form coils (30 rosettes)>>every 10 coils>>chromatid