DNA

Question 1

relationship between chromosomes, DNA, genes

Answer 1

chromosomes is condensed DNA, genes are short sections of DNA

Question 2

why does DNA need to replicate

Answer 2

• to produce new cells, pass genetic information to ‘daughter’ cells
• for growth + general replacement when other cells die
• to heal injuries

Question 3

shape of DNA

Answer 3

made up of two strands, twisted into a double helix

Question 4

four types of nitrogenous bases

Answer 4

• adenine
• guanine
• thymine
• cytosine

Question 5

function of helicase in DNA replication

Answer 5

to unzip the DNA; creating a replication fork of DNA stands after they are separated

Question 6

function of primase in DNA replication

Answer 6

creates an RNA primer, which takes bases and matches their corresponding DNA bits

Question 7

function of polymerase III in DNA replication

Answer 7

creates new DNA/adds DNA bases from 5 to 3 end

Question 8

difference between leading strand and lagging strand

Answer 8

leading strand: DNA made continuously after primer; goes from 5 to 3
lagging strand: goes from 3 to 5; DNA must be made in Okazaki fragments

Question 9

Okazaki fragment

Answer 9

a small section of DNA, created on the lagging strand before two primers

Question 10

function of polymerase 1in DNA replication

Answer 10

uses exonuclease activity to remove primers and fill gaps with DNA bases

Question 11

function of ligase in DNA replication

Answer 11

seals up DNA strands and makes it one continuous strand of DNA

Question 12

nitrogenous bases

Answer 12

ACTG, is the ‘information’

Question 13

sugar phosphate backbone

Answer 13

two of them, creates the ‘rails’ of the DNA

Question 14

base pairings

Answer 14

C + G, A + T

Question 15

DNA groups

Answer 15

deoxyribose sugar, phosphate, nitrogenous bases

Question 16

nucleotide

Answer 16

basic building block of DNA: made up of phosphate, deoxyribose sugar, and a nitrogenous base bound together