B1.7.2 - Reproduction Flashcards
How many forms of reproduction are there?
Two
What’s sexual reproduction?
the fusion of 2 gametes (male and female). The mixture of genetic information = variety in offspring!
What’s asexual reproduction?
NO fusion of gametes and only 1 individual is needed as the parent. No mixing of genetic info so NO VARIATION IN OFFSPRING.
How many chromosomes does each gamete contain?
23, half the number found in all other body cells
What happens when the male and female gamete fuse?
It becomes a zygote! This becomes an embryo with a full set of 46 chromosomes! Half from mum, half from dad!
What are genetically identical individuals known as?
Clones
How can new plants be produced quickly and cheaply?
By taking cuttings from older plants
What are modern cloning techniques?
- tissue culture
- embryo transplants
- adult cell cloning
What is the cloning technique of tissue culture? (asexual)
It’s using small groups of cells from part of a plant
What are embryo transplants? (asexual)
Splitting apart cells from a developing animal embryo before they become specialised, then transporting the identical embryos into host mothers
What’s a host mother?
A mother that births a baby but didn’t have sex
like the Virgin Mary but more sciencey
What are the 5 steps of adult cell cloning? (asexual)
- nucleus removed from UNfertilised egg cell
- nucleus from adult body cell inserted into egg cell
- electric shock activates cell division to form embryo cells
- embryo (whilst cell ball) inserted into womb of adult female
- BABY! (identical to animal that donated body cell)
What are genes from chromosomes of humans and other organisms cut out with?
enzymes!
and they’re transferred to cells of other organisms
Why are genes transferred to cells of animals, plants or microorganisms at early stages?
So they develop with desired characteristics!
What can new genes be transferred to, related to plants?
CROP PLANTS!
