Natural selection and breeding Flashcards
what is intraspecific variation?
intraspecific variation is variation between animals from the same species
what is interspecific variation?
interspecific variation is variation between different species.
selective breeding
where humans breed plants or animals to exhibit particular characteristics(AKA artificial selection).
allele?
each form of a gene
characteristic?
a distinguishing trait, quality or property
embryo?
the body of an organism in its early stage development from a zygote. made up of unspecialised cells.
zygote?
a diploid cell resulting from the fusion of two haploid gametes
somatic cell?
cells that make up an organism which are not gametes, germ cells of stem cells.
gamete
sex cells(ova/sperm)
enucleate?
to remove the nucleus from the cell
mitosis
a type of cell division where 2 identical diploid cells are formed. used to make non reproductive cells.
surrogate
carries a foetus conceived by another female organism
natural selection
the process whereby organisms better adapted to their environment tend to survive and produce more offspring
adaptation
the process by which an organism or species becomes better suited to the environment.
clone
a genetically identical cell or organism
process of cloning
a nucleus is taken from a body cell(somatic cell). this nucleus is put into an enucleated ovum cell. The cell is given a mild electric shock to help it divide in a process called mitosis. a ball of cells is produced(embryo).. it is then placed into the uterus of the surrogate mother.
reasons for selective breeding
-usefulness
-appearance
disease resistance in food crops
animals which produce more meat and milk
Advantages of cloning
Increase in population of endangered animals.
Animals that find it difficult to breed can produce off spring.
Improves/ increase food supply
Disadvantages of cloning.
Reduction in genetic variation
Unable to adapt to new environments.
problems with selective breeding
genetic mutations
defects in plants/ animals
reduces variety
will all selectively bred animals look the same?
no because;
depends on environments
diff. types of soils
nitrates- protein for growth
water- photosynthesis(🌿)
wind-reduced height of plant
magnesium-chlorophyll for 🌿
selective breeding in plants(steps)
- decide characteristics
2.select the plants that have this characteristic. - use cotton bud to collect pollen from selected plants.
4.uncover stigmas. brush pollen onto them. - cover plant
6.some pollen grains grow tubes. pollen cell nuclei move down and fuse with egg nuclei(fertilisation)
7.let it develop
8.collect plant and seed
9.wait for seed to grow into plant.
10 repeat!!!!!!
