B1.7 Flashcards
What is variation?
The difference between individuals of the same species
What two things can affect variation?
~ Genetic causes
~ Environmental causes
What are clones?
Genetically identical individuals
What method is used to clone plants?
Tissue culture
~ Group of cells taken from plant
~ Cells are put in agar jelly
~ Cells grow to plants which are then placed in soil
What methods are used to clone animals?
Embryo transplants
~ Two ‘best’ animals mate
~ The embryo is split into balls of smaller cells
~ Individual small balls of cells are placed in the womb of host mothers
Adult cell cloning
~ Skin cell is taken from ‘best’ animal and nucleus is taken out
~ Egg cell is taken from another animal, nucleus is removed, and nucleus from the ‘best’ animal is placed in this egg cell
~ This new egg cell is given an electric shock and placed in a host mother
How many parents does asexual reproduction require?
1
Which type of reproduction produces identical copies of the parent (clone)?
Asexual
Which type of reproduction requires fertilisation of gametes?
Sexual
What do genes do?
Produce proteins which control our features
What are some characteristics that are caused by both genes and your environment?
~ Weight
~ Height
~ Metabolism
What is genetic engineering?
The transfer of genes from one living thing to another
What is sexual reproduction?
~ Fusion of male and female gametes
~ Egg and sperm pass on genes
~ Offspring will have variation
What is asexual reproduction?
~ Involves one parent and no gametes
~ No mixing of genes
~ Offspring are clones
What are the two types of variation?
Genetic and environmental
Why may crops be genetically modified?
~ To improve the crop yield
~ To improve resistance to pests or herbicides
