6.2 Role of chromosomes and DNA

Question 1

What is a chromosome?

Answer 1

a thread-like structure composed of DNA and proteins

Question 2

What are chromosomes composed of?

Answer 2

DNA and protein (histones)

Question 3

What is DNA and what does it stand for?

Answer 3

Deoxyribonucleic acid (DNA) contains four bases which form the major parts of the chromosome and containes coded genetic instructions

Question 4

What are the 4 bases?

Answer 4

Adenine, Thymine, Cytosine, Guanine

Question 5

What is a nucleosome?

Answer 5

A section of supercoiled DNA around
histones
when combined with other nucleosomes, it forms tightly compact DNA

Question 6

What is a chromatin?

Answer 6

mass of genetic material composed of DNA and histones that condense to form chromosomes

Question 7

What is the difference in shape of chromosomes between eukaryotic and prokaryotic cells?

Answer 7

Eukaryotic has linear while prokaryotic have circular

Question 8

Why is DNA in prokaryotic cells less condensed?

Answer 8

They do not contain histones in the supercoiling process

Question 9

What happens if DNA is not packaged properly?

Answer 9

-Will not physically fit in cell, loss of genetic info
-Cell will not be able to distribute DNA during cell division so daughter cells will not recieve correct genetic info

Question 10

Why is it good to condense DNA?

Answer 10

It allows a lot of genetic info to be stored in the cell