topic 7

Question 1

What is the definition of gene mutations

Answer 1

the change in nucleotide bases

Question 2

what is a genome

Answer 2

the whole genetic material of an organism

Question 3

what is an allele

Answer 3

different form of the same gene
- changes the base sequence of nucleotide
-means the amino acid sequence changes and forms a different protein

Question 4

What is a diploid and haploid cell?

Answer 4

Diploid- contains 2 set of chromosomes
Haploid- contains 1 sets of chromosomes

Question 5

What’s a homologous chromosome

Answer 5

Chromosomes which carry the same genes in the same loci
-has the same characteristics

Question 6

What are the non functional protein mutations?

Answer 6

Deletion- deleters bases meaning amino acid sequence cant be formed as triplet no longer matches. Also results in a frame shift
-adition
adding more bases causes different triplet
Duplication-one or more bases are repeated
-frame shift

Question 7

Where might /when/ might gene mutation occur

Answer 7

spontaniously
During Dna replication
x rays

Question 8

What does a gene mutation do

Answer 8

means that the nucleotide bases change so a different protein may be formed or make non functional ones

Question 9

What might the change of amino acids change the positions of

Answer 9

the hydrogen and ionic bonds of a protein as a new one is being produced so primary structure has changed and therefore the tertiary structure.

Question 10

Where do alleles differ

Answer 10

the nucleotide bases.

Question 11

What’s the purpose of mitosis

Answer 11

.Creates identical chromosomes to parents
.Growth and repair
.Identical diploid cells
.to produce genetically similar cells

Question 12

What’s the first stage of mitosis

Answer 12

Interphase
-preparation of nuclear division
-Dna is doubled
-Cell membrane structures are replicated
-more apt is produced
-increase of protein synthesis

Question 13

What’s the second stage of mitosis

Answer 13

prophase
-chromosomes form 2 sister chromatids, which are joined by the centromere
-Nucleur membrane breaks down
-centrioles move to opposite ends of the poles

Question 14

What’s the third stage of mitosis

Answer 14

metaphase

• Sister chromatids are aligned in the centre via spindle fibres
  -spindle fibres are made from protein

Question 15

What’s the 4th stage of mitosis

Answer 15

Anaphase
- spindle fibres pull the cromoatids to opposite poles and split

Question 16

What’s the 5th stage of mitosis

Answer 16

Telophase
-sister chromatids uncoil
-nucleur membrane reforms
-two cells are genetically identical to each other

Question 17

What’s the last stage of mitosis

Answer 17

Cytokenisis
-cytoplasm splits in two
-two new cells form as a cell surface membrane.

Question 18

Why does meiosis produce gametes

Answer 18

cell divides twice so 4 cells are produced. These cells contain half of the chromosomes so they are haploid cells . These are gametes.

Question 19

What’s the difference between mitosis and meiosis

Answer 19

Mitosis divides once , mitosis 2 times
Mitosis same cells . Meosis diff
Mitosis 2 diploid,meosis 4 haploid

Question 20

What’s the first stage of meiosis

Answer 20

Late interphase
-dna doubled
-atp produced
-organells replicated

Question 21

First proper stage of meiosis

Answer 21

Meosis I
The homologous chromosomes split into 2