Inheritance, Variation and Evolution

Question 1

What is Asexual reproduction

Answer 1

Involves one parent
no mixing of genetic information
daughter cells are produced by mitosis, offspring will have same genes so they are clones
eg-strawberry and daffodils

Question 2

What is Sexual reproduction

Answer 2

2 parents
Gametes fuse at fertilisation (involves meiosis)
one chromosomes comes from each parent

DIPLOID-FULL SET-46 chromosomes
HALOID-1/2 SET-23 chromosomes

Question 3

What is Meiosis?

Answer 3

sex cells are produced by cell division in the ovaries and testes

Question 4

Describe the Structure of DNA?

Answer 4

DNA is a polymer made up of repeating units called nucleotide
each nucleotide consists of :
- a sugar
-a phosphate
-a base A and T, C and G

Question 5

What is Protein synthesis?

Answer 5

It occurs in a tiny structure called ribosomes. To make protein these structure use the code in the DNA

Question 6

What is a mutation?

Answer 6

A change in the DNA structure is called a mutation
A few mutation that cause the protein to have a different shape;
if it is an enzyme, the substrate will not fit in the active site
if it is structural protein ,it may lose its strengt

Question 7

What is Polydactyl?

Answer 7

-Having and extra finger or toe caused by a dominant allele

Question 8

Genotypes

Answer 8

BB -Homozygous dominant
Bb-Heterozygous
bb-Homozygous recessive

Question 9

What is a gene?

Answer 9

Stretch of DNA codes for characteristics

Question 10

What is a gamete and chromosome?

Answer 10

Gamete -sex cell

chromosomes-bundled up DNA

Question 11

What is the difference between dominant and recessive?

Answer 11

Dominant-only need 1 gene to express the characteristic

Recessive-needs 2 identical recessive genes to express characteristic

Question 12

What is the difference between homozygous and heterozygous?

Answer 12

homozygous-genes are the sae

heterozygous-genes are different

Question 13

What is a phenotype and a genotype?

Answer 13

Phenotype-collection of characteristics that you have

genotype-what genes you have

Question 14

What is cystic fibrosis?

Answer 14

Affects the lungs and builds up mucus in the respiratory system which cannot be removed naturally
caused by recessive allele

Question 15

Do all parts of DNA code for protein?

Answer 15

NOT ALL PARTS OF DNA CODE FOR PROTEINS

-Non-coding parts switch genes on and off so the can/cannot make specific proteins

Question 16

What is the process of Protein synthesis?

Answer 16

1) A section of DNA is converted to RNA
2) Single strand of RNA leaves the nuclease
3) RNA binds to a ribosome. Codes for each amino acid in the sequence

Question 17

How des Meiosis begin?

Answer 17

1) Cell with 2 pairs of chromosomes (diploid cell)

2) Each chromosome replicates itself

Question 18

What happens after they replicate?

Answer 18

3) Chromosomes part company and move to opposite poles

4) Cell divides for the first time

Question 19

What are the last stages of meiosis?

Answer 19

5) Copies now separate and the second cell division takes place
6) Four haploid cells each with half the number of chromosomes of the parent cell