Reproduction

Question 1

what is asexual reproduction

Answer 1

not involving gametes

Question 1

what is sexual reproduction

Answer 1

reproduction that involves gametes(sex cells) sperm and egg, pollen and ovum

Question 2

define haploid cells and give examples

Answer 2

having a single set of chromosomes in the cell. e.g. gametes

Question 3

define diploid cells and give examples

Answer 3

having two complete sets of chromosomes in cells. e.g. animal cells minus gametes

Question 4

sexual reproduction process

Answer 4

• gametes produced by meiosis
• male gamete transferred to female gamete
• fertilisation - sperm fuses with the egg / pollen fuses with ovum
• zygote develops
• zygote divides by mitosis to form a new organism

Question 5

asexual reproduction process

Answer 5

Diploid cells divide by mitosis. offspring genetically identical to parents. Asexual reproduction types: bulbs, runners, cuttings

Question 6

how gametes are produced

Answer 6

meiosis. meiosis produces non identical and have half the chromosomes of the original

Question 7

advantages of asexual and sexual reproduction

Answer 7

asexual:
in stable environments as offspring and parents have identical adaptations. Faster and more energy efficient.
sexual:
in changing environments produces some offspring which are better adapted than parents

Question 8

fertilisation

Answer 8

sperm approach egg and penetrate. nucleus of sperm enter the egg and fuse with nucleus of egg. fertilisation membrane forms to prevent other sperm from entering.

Question 9

internal vs external fertilisation

Answer 9

internal e.g mammals and birds. fertilisation in the female body. male ejaculate sperm into female. good as no outside interference

external e.g fish
females lay eggs in water and males release sperm in the water as well. fertilisation takes place outside the human body. often some mating behaviour to ensure the male and female are in the same place