DNA structure and replication

Question 1

What does DNA stand for

Answer 1

Deoxyribonucleic acid

Question 2

What is DNA made of

Answer 2

DNA is made of small molecules called nucleotides

Question 3

What are the three nucleuotides called

Answer 3

A Phosphate group
A Deoxyribose sugar
A Nitrogenous base

Question 4

How are nucleotides arranged

Answer 4

Nucleotides are arranged in a spiral structure called a double helix

Question 5

What does the sugar and phosphate make up in DNA

Answer 5

They make up the sides of the ladder

Question 6

What do nitrogenous bases make up in DNA

Answer 6

They make up the steps of the ladder

Question 7

What are all four Nitrogenous Bases

Answer 7

Adenine
Thymine
Guanine
Cytosine

Question 8

How do Nitrogenous Bases pair up

Answer 8

Adenine (A) Pairs with Thymine and Cystoside (C) pairs with Guanine

A - T
C - G

Question 9

What are the three stages of DNA replication

Answer 9

Step one : Straightening and seperation (Unzipping)

Step two : Constructing copies

Step three : Checking for mistakes (proofreading)

Question 10

How does stage 1 of DNA replication occur

Answer 10

The double helix untwists
Enzyme separates the nitrogenous bases exposing them

Question 11

How does stage 2 of DNA replication occur

Answer 11

Free nucleotides connect to the exposed nitrogenous bases following the pairing rules AT and CG. This forms 2 identical DNA strands

Question 12

How does stage 3 of DNA replication occur

Answer 12

two double helixes are formed and they are both proofread by enzymes

Any mistakes are corrected