Inheritance

Question 1

Chromosomes

Answer 1

made of DNA, which contains genetic information in the form of
genes.

Question 2

A gene is a

Answer 2

a length of DNA that codes for a protein.

Question 3

An allele is an

Answer 3

alternative form of a gene.

Question 4

female chromosomes

Answer 4

XX

Question 5

male chromosomes

Answer 5

XY

Question 6

The sequence of bases in a gene determines the

Answer 6

sequence of amino acids used to make a specific protein.

Question 7

Different sequences of amino acids give

Answer 7

different shapes to protein molecules.

Question 8

DNA controls cell function by

Answer 8

controlling the production of proteins, including
enzymes, membrane carriers and receptors for neurotransmitters

Question 9

How protein is made:

Answer 9

the gene coding for the protein remains in the nucleus
messenger RNA (mRNA) is a copy of a gene
mRNA molecules are made in the nucleus and move to the cytoplasm
the mRNA passes through ribosomes
the ribosome assembles amino acids into protein molecules
the specific sequence of amino acids is determined by the sequence of bases in
the mRNA

Question 10

Most body cells in an organism contain the same genes, but many genes in a
particular cell are not

Answer 10

expressed because the cell only makes the specific proteins it
needs. For instance, the cells in salivary gland don’t need to make protease but they
have the gene for it which is not expressed because the cell doesn’t need it.

Question 11

A haploid nucleus

Answer 11

is a nucleus containing a single set of chromosomes

Question 12

A diploid nucleus

Answer 12

is a nucleus containing two sets of chromosomes

Question 13

In a diploid cell,

Answer 13

there is a pair of each type of chromosome and in a human diploid
cell there are 23 pairs.

Question 14

Mitosis

Answer 14

nuclear division giving rise to genetically identical cells

Question 15

Role of mitosis

Answer 15

in growth, repair of damaged tissues, replacement of cells and
asexual reproduction.

Question 16

Process of mitosis

Answer 16

The exact replication of chromosomes occurs before mitosis.
During mitosis, the copies of chromosomes separate, maintaining the chromosome
number in each daughter cell.

Question 17

Stem cells is unspecialised cells that divide

Answer 17

by mitosis to produce daughter cells that
can become specialised for specific functions.

Question 18

Meiosis is involved in the

Answer 18

production of gametes

Question 19

Meiosis

Answer 19

reduction division in which the chromosome number is halved from
diploid to haploid resulting in genetically different cells

Question 20

Inheritance

Answer 20

transmission of genetic information from generation to generation

Question 21

Genotype

Answer 21

the genetic make-up of an organism.

Question 22

Phenotype

Answer 22

the observable features of an organism.

Question 23

Homozygous

Answer 23

having two identical alleles of a particular gene

Question 24

Two identical homozygous individuals that

Answer 24

breed together will be pure-breeding.

Question 25

Heterozygous

Answer 25

having two different alleles of a particular gene.

Question 26

A heterozygous individuals will not be

Answer 26

pure-breeding.

Question 27

dominant allele

Answer 27

is an allele that is expressed if it is present in the genotype

Question 28

recessive allele

Answer 28

an allele that is only expressed when there is no dominant allele
of the gene present in the genotype.

Question 29

Codominance

Answer 29

a situation in which both alleles in heterozygous organisms
contribute to the phenotype

Question 30

A sex-linked characteristic

Answer 30

a feature in which the gene responsible is located on a
sex chromosome and that this makes the characteristic more common in one
sex(usually male) than in the other.

Question 31

example of sex linkage.

Answer 31

Red-green colour blindness