Asexual and Sexual reproduction Flashcards
What is asexual reproduction?
Asexual reproduction is the production of offspring without involving sex cells (gametes)
What are the 5 different ways asexual reproduction organisms reproduce?
1) binary fission
2) fragmentation
3) vegetative propagation
4) budding
5) spores
What is binary fission? Who uses binary fission?
Separation of the body into two new seperate bodies. Single celled organisms e.g bacteria.
What is fragmentation? who uses fragmentation?
where a fragment of the parent breaks off and develops into an entirely new individual. larger more complex animals e.g starfish.
What is vegetative propagation? who uses vegetative propagation?
when they grow from cuttings or runners out from their bodies. multi cellular plants e.g strawberries
What is budding? Who uses budding?
Involves the development of small ‘buds’ that enlarge and break off to become new individuals. e.g hydra
What is spores? who uses spores?
that are easily dispersed via wind away from the parent organism, usually found under their leaves. Fungi and plants e.g mushroom and ferns
What are the advantages in asexual reproduction?
- energy efficient
- produce large numbers of offspring very rapidly
What are the disadvantages in asexual reproduction?
- They are genetically identical ‘clones’ of the parent therefore, have a higher risk of not surviving severe environmental changes
- Such populations may face extinction
what is sexual reproduction?
Sexual Reproduction involves the union (fertilisation) of sex cells (gametes) to form a zygote (a single fertilised cell).
How to describe fertilisation?
the action or process of fertilising an egg or a female animal or plant, involving the fusion of male and female gametes to form a zygote.
What are the 2 types of fertilisation?
1) internal fertilisation
2) external fertilisation
What is internal fertilisation?
fertilisation occurs inside the female reproductive system
What is external fertilisation?
fertilisation occur outside the female reproductive system …..often in a watery environment
What are the two major types of gametes?
1) ova
2) sperm
What are the organs called that produce these gametes?
gonads
What are the female and male gonads called?
1) male gonads which produce sperm are called testes
2) female gonads which produce ova are called ovaries
What are the advantages in sexual reproduction?
- show great variation (diversity) of characteristics in their offspring.
- variation is an advantage in a changing environment
What are the disadvantages in sexual reproduction?
- energetically very expensive
- Parents expend energy finding and attracting mates
- parents must also produce gametes and ensure that the gametes are brought together at the right time
What is the fertilised egg called straight after fertilisation?
Zygote
What is the zygote called after the cells start to divide?
Embryo
