Natural selection

Question 1

Alleles

Answer 1

different versions of the same gene

Question 2

asexual reproduction

Answer 2

reproduction which requires only one parent; results in clones

Question 3

Cancer

Answer 3

a disease which occurs as the result of cell changes that lead to uncontrolled growth and division

Question 4

Clone

Answer 4

an organism which is genetically identical to its parent

Question 5

continuous variation

Answer 5

variation which can take any value between a minimum and a maximum

Question 6

Discontinuous variation

Answer 6

characteristic which falls into distinct groups

Question 7

dominant allele

Answer 7

version of a gene whose characteristics is always expressed if present in the genotype

Question 8

environmental variation

Answer 8

variation caused by the environment

Question 9

fertilisation

Answer 9

joining together of two gametes

Question 10

gametes

Answer 10

Sex cells

Question 11

genetic cross

Answer 11

technique used to show the possible characteristics of an offspring

Question 12

genetic variation

Answer 12

variation caused by an organism’s genetic material

Question 13

genome

Answer 13

all the genetic material present in an organism

Question 14

genotype

Answer 14

the combination of alleles present in an organism

Question 15

mutation

Answer 15

change in the sequence of DNA bases

Question 16

Punnett square

Answer 16

diagram used to show the possible genetic makeup of offspring, based on a mother’s and a father’s genes

Question 17

recessive allele

Answer 17

version of a gene whose characteristic is only expressed if two copies are present in the genotype

Question 18

sexual reproduction

Answer 18

reproduction requiring two parents, which results in variation

Question 19

variation

Answer 19

differences within a species