Unit: 1 - The structure and organization of DNA

Question 1

What is DNA made up of?

Answer 1

DNA consists of two strands of repeating units called nucleotides. Nucleotides are composed of phosphate, deoxyribose sugar and a base.

Question 2

What are the four bases found in DNA?

Answer 2

There are four bases in DNA: (A) adenine, (T) thymine, (G) guanine and (C) cytosine. Each nucleotide has a different base.

Question 3

What is the base pairing rule for the bases in DNA?

Answer 3

These bases follow the base pairing rules: A always pairs with T, and G always pairs with C. The bases are held together by hydrogen bonds.

Question 4

What’s the form of DNA?

Answer 4

DNA takes the form of a double helix.

Question 5

DNA is made up of two antiparallel strands. This means the strands run in opposite directions to each other

Answer 5

What are the two strands called that makes up DNA?

Question 6

What shapes can a molecule of DNA take form of?

Answer 6

DNA is a double-stranded molecule that can either be circular or linear

Question 7

What are prokaryotes?

Answer 7

Prokaryotes are organisms which lack a true membrane-bound nucleus

Question 8

Give an example of a prokaryote?

Answer 8

Bacteria are an example of a prokaryote

Question 9

Where’s the DNA of a prokaryote located?

Answer 9

Their DNA is found in the cytoplasm of the cell.

Question 10

What type of chromosome shape does a prokaryote have?

Answer 10

Prokaryotes have a large circular chromosome. They may also have smaller rings of DNA called plasmids.

Question 11

What are the smaller rings of DNA in prokaryotes called?

Answer 11

Plasmids

Question 12

What’s an eukaryote?

Answer 12

Eukaryotes are organisms which have a membrane bound nucleus that stores their genetic material

Question 13

Give an example of a eukaryote?

Answer 13

Animals, plants and fungi are examples of eukaryotes.

Question 14

Which eukaryote has linear chromosomes?

Answer 14

Circular plasmids may also be found in yeast (a fungus), which is classified as a eukaryote

Question 15

What shape does an eukaryote’s DNA take form of?

Answer 15

In eukaryotes, DNA is found tightly coiled into linear chromosomes

Question 16

Where’s the DNA of an eukaryote stored?

Answer 16

DNA is also found within mitochondria (mtDNA) where it forms circular chromosomes

Question 17

Where else is DNA stored in plant cells?

Answer 17

DNA can also be found within the chloroplasts of plant cells

Question 18

Describe DNA in chloroplasts compared to the mitochondrial DNA?

Answer 18

It is usually larger than mitochondrial DNA and takes the form of circular chromosomes containing the genes involved in the photosynthetic process

Question 19

What protein is packaged with linear chromosomes?

Answer 19

Packaged with histones