Genetics revision PART 2 TEST

Question 1

What is the subunit called that makes up DNA

Answer 1

Nucleotide

Question 2

Name the four base pairs and state the base paring rule

Answer 2

Adenine pairs with Thymine
Cytosine pairs with Guanine

Question 3

What is mitosis

Answer 3

division of diploid somatic cells into 2 identical cells, for growth and repair

Question 4

what is meiosis

Answer 4

Is the process by which the gonads produce haploid gametes. (Sex cells)

Question 5

Contrast mitosis and meiosis

Answer 5

Mitosis only involves one cell division and produces two daughter cells.

Where as Meiosis involves two cell divisions but produces 4 duaghter cells.

Question 6

Are the daughter cells identical or different to the parent cells.

Answer 6

In mitosis the duaghter cells are identical to the parent cells.
In meosis the daughter cells are different to the parent cells.

Question 7

What is an allele?

Answer 7

Allelles are versions of a gene that code for a same trait

Question 8

how many chromsomes in a human body cell

Answer 8

46

Question 9

is a body cell haploid or diploid

Answer 9

diploid

Question 10

Contrast between genotype and phenotype

Answer 10

Genotype refers to the genetic characteristics of an organism . Examples of genotype are eye colour and height

Phenotype refers to physical characteristics or traits like appearances

Question 11

define genotype

Answer 11

the combination of alleles inherited for a particular characteristic.

Question 12

define phenotype

Answer 12

outward expression, appearance, description of a characteristic

Question 13

Homozygous

Answer 13

a genotype in which the two alleles are identical, (BB bb)

Question 14

Heterozygous

Answer 14

a genotype in which the two alleles are different (Bb)

Question 15

how many pairs of homologous chromsomes do human females have

Answer 15

23 homologous

Question 16

how many pairs of homolgous pairs do males have

Answer 16

22 homolougous

Question 17

what is the function of a punnet square

Answer 17

is used to predict the outcome of a genetic cross

Question 18

what information do u need when completring a punnet square

Answer 18

genotype of parents

Question 19

why do sex linked traits occur in males more than females

Answer 19

because males don’t have another X chromosome to make the recessive gene
females need 2 of the recessive allele males need only 1

Question 20

what is a sex linked gene

Answer 20

Genes located on sex chromsome

Question 21

x linkage

Answer 21

genes located on the x chrsomome