S3 Biology- Unit 2.1: Reproduction and Survival

Two types of reproduction

asexual and sexual

amount of parents needed for sexual reproduction

2

amount of parents needed for asexual reproduction

1

which type of reproduction needs sex cells

sexual

in asexual reproduction the offspring is a _ of the parent

clone

name two pros of asexual reproduction

rapidly increases population, very fast

name two cons of asexual reproduction

no genetic variation, can't tolerate changes to the environment

name a plant asexual reproduction occurs in

strawberries

two types of natural asexual reproduction

vegative and natural propagation

how does asexual reproduction happen in plants

new plants grow from parts of the parent plant

Sex cells are called what?

gametes

what do the parents have that produce sex cells in sexual reproduction

sex organs

in sexual reproduction what do the parents provide

a set of chromosomes/genetic information

pro of sexual reproduction

genetic variation

Why is genetic variation important?

species can adapt to new environments and disease is less likely to affect all individuals. this means the species can survive longer

Cons of sexual reproduction

you need to find a mate because one person can't reproduce and it takes a lot longer than asexual reproduction the

How do fish reproduce?

fish sperm meets eggs in the water

How do humans reproduce?

sperm from testicles travelling up the sperm duct and being placed in the vagina by the penis to them travel and fertilise the egg in the oviduct

what do the nuclei of male and female sex cells have to do in order to produce new offspring

fuse

male gametes are called (plants and animals)

sperm and pollen

female gametes are called (plants and animals)

eggs and ovules

How does genetic variation occur?

genetic information mixing during fertilisation

what is the stage before an embryo

zygote

what is external fertilisation

Fertilisation where a male organism's sperm fertilising a female organism's egg outside of the female's body. (like in water)

what organism does external fertilisation

fish

external fertilisation produces _ amount of gametes

enormous

cons of external fertilization

eggs receive no protection, wasteful and less chance of a successful baby

what is internal fertilisation

occurs when males release sperm in the female body

wha organisms do internal fertilisation

land mammals

does internal fertilisation produce more or less gametes than external

much less

pros of internal fertilization

more efficient, less waste, fertilization is more likely and baby is more protected

what are the parts of the male reproductive organs

urethra, prostate, penis, testes and sperm duct

What does the urethra do?

carries sperm and urine out of the body

what does the penis do

allows sperm and urine to leave the body

what do the testes do

produce sperm and testosterone

What does the prostate do?

produces semen

what are the parts of the female reproductive organ

ovaries, vagina, oviduct, uterus and cervix

what do the ovaries do

contains egg cells

What does the vagina do?

allows sperm to enter during sex

What does the oviduct do?

site of fertilization

What does the uterus do?

where fertilised ovum develops into a baby