Sexual reproduction and meiosis

Question 1

diploid (2n)

Answer 1

a cell with a nucleus containing two full sets of chromosomes

Question 2

haploid (n)

Answer 2

a cell with a nucleus containing one complete set of chromosomes

Question 3

zygote

Answer 3

the cell formed when two haploid gametes fuse at fertilisation

Question 4

fertilisation

Answer 4

the fusing of the haploid nuclei from two gametes to form a diploid zygote in sexual reproduction

Question 5

polyploidy

Answer 5

a cell or an organism with more than two sets of chromosomes

Question 6

gonads

Answer 6

the sex organs in animals

Question 7

ovaries

Answer 7

the female sex organs in both animals and plants; they produce the female gametes called ovules in plants and ova in animals

Question 8

anthers

Answer 8

male sex organs in plants that produce the male gametes contained in the pollen

Question 9

ovules

Answer 9

the haploid female gametes in plants

Question 10

pollen

Answer 10

the spore which contains the haploid male gametes of plants

Question 11

testes

Answer 11

the male sex organs in animals that produce the male gametes: sperm

Question 12

spermatozoa (sperm)

Answer 12

the haploid male gametes in animals

Question 13

ova

Answer 13

the haploid female gametes in animals (singular= ovum)

Question 14

microspores

Answer 14

the result of meiosis in plants that develop into the spore (pollen) containing the male gametes

Question 15

megaspores

Answer 15

the result of meiosis in plants that develop into the female gametes, ovules

Question 16

homologous pairs

Answer 16

matching pairs of chromosomes in an individual which both carry the same genes, although they may have different alleles

Question 17

crossing over (recombination)

Answer 17

the process by which large multi-enzyme complexes cut and re-join parts of the maternal and paternal chromatids at the end of prophase 1, introducing genetic variation

Question 18

chiasmata

Answer 18

the points where the chromatids break during recombination

Question 19

mutation

Answer 19

a permanent change in the DNA of an organism

Question 20

independent assortment (random assortment)

Answer 20

the process by which the chromosome derived from the male and female parent are distributed into the gametes at random