Inheritance

Question 1

heredity

Answer 1

The

inheritance of such characteristics is called heredity

Question 2

gentics

Answer 2

The

inheritance of such characteristics is called heredity

Question 3

chromosome

Answer 3

A chromosome is a thread of DNA, made up of a string of

genes

Question 4

gene

Answer 4

A gene is a length of DNA that codes for a protein

Question 5

what is inside chromosome

Answer 5

Inside a nucleus are thread-like structures called
chromosomes which can be seen most clearly at the
time when the cell is dividing.

Question 6

centromere

Answer 6

Each chromosome
has certain characteristics when ready to divide: there
are two chromatids, joined at one point called a
centromere

Question 7

Each chromatid is a string of

genes,

Answer 7

coding for the person’s characteristics

Question 8

A human body (somatic) cell nucleus contains

Answer 8

46 chromosomes

Question 9

The

only pair that do not necessarily match is chromosome

Answer 9

chromosome

pair 23: the ‘sex chromosomes’

Question 10

The Y chromosome is

much smaller than the

Answer 10

x chromosome

Question 11

sex chromosomes

Answer 11

Whether you are a male or female depends on the

pair of chromosomes called the ‘sex chromosomes’

Question 12

In females, the two sex chromosomes, called

Answer 12

the X chromosomes, are the same size as each

other XX

Question 13

In males,he two sex chromosomes are of

Answer 13

different sizes. XY

Question 14

mitosis

Answer 14

Mitosis is nuclear division giving rise to genetically

identicalcells.

Question 15

why is mitosis importance

Answer 15

The processes of growth, repair and replacement

of cells all rely on mitosis.even if an organism is asexual

Question 16

meiosis

Answer 16

Meiosis is nuclear division, which gives rise to cells that are
genetically different.

Question 17

The process of meiosis takes place in

Answer 17

the gonads
of animals (e.g. the testes and ovaries of mammals,
and the anthers and ovules of fl owering plants). the cells formed are gametes.

Question 18

an allele

Answer 18

is a version of a gene

Question 19

Genotype

Answer 19

Genotype is the genetic make-up of an organism in terms of

the alleles present.

Question 20

phenotype

Answer 20

Phenotype is the features of an organism

Question 21

homozygous

Answer 21

Homozygous means having two identical alleles of a
particular gene e.g. TT, where T is tall. Note that two
identical homozygous individuals that breed together will
be pure-breeding

Question 22

heterozygous

Answer 22

Heterozygous means having two different alleles of a
particular gene e.g. Tt. Note that a heterozygous
individual will not be pure breeding.

Question 23

types of allele’s

Answer 23

An allele that is expressed if it is present is dominant.
An allele that is only expressed when there is no dominant
allele of the gene present is recessive.

Question 24

co-dominant

Answer 24

If both genes of an allelomorphic pair produce their
effects in an individual (i.e. neither allele is dominant
to the other) the alleles are said to be co-dominant