DNA, Genes and Chromosomes 4A

Question 1

Nuclear eukaryotic DNA structure

Answer 1

Linear DNA which exists as chromosomes which are found in the nucleus
The DNA molecule is associated with histones

Question 2

Mitochondria and chloroplast DNA in eukaryotes

Answer 2

circular, shorter than DNA in the nucleus and not associated with histones

Question 3

Prokaryotic DNA structure

Answer 3

Carry DNA as chromosomes but it is circular and shorter than eukaryotic DNA not associated with histones.

Question 4

How does prokaryotic DNA condense

Answer 4

By supercoiling

Question 5

What is a gene

Answer 5

A sequence of DNA bases that either codes for a polypeptide or functional RNA.

Question 6

How many bases code for one amino acid and what is this called

Answer 6

3
A triplet

Question 7

How is a polypeptide made

Answer 7

DNA is copied into mRNA - first stage of protein synthesis

Question 8

What is function RNA

Answer 8

RNA other than mRNA which perform special tasks during protein synthesis

Question 9

What is a genome

Answer 9

The complete set of genes in a cell

Question 10

What is a cell’s proteome

Answer 10

the full range of proteins that the cell is able to produce

Question 11

Define an intron

Answer 11

The sections of DNA in a sequence that do not code for polypeptides

Question 12

Define an exon

Answer 12

The sections of a gene that do code for an amino acid

Question 13

When are introns removed

Answer 13

During protein synthesis so they do not affect the amino acid order

Question 14

Define non-coding repeats

Answer 14

Regions of multiple repeats outside of genes

Question 15

Define an allele

Answer 15

All the different forms of a gene

Question 16

Define homologous pair

Answer 16

both chromosomes are the same size and have the same genes although they could have different alleles

Question 17

Define locus

Answer 17

fixed position on the allele