Variation, Reproductio And New Technology Flashcards
The chromosome threads carry the …….
Genes
In the nuclei of ……….. there is only a ………… Set of chromosomes
Gametes
Single
When are genes passed on?
During sexual reproduction
What do genes control?
Different characteristics in offspring
What is asexual reproduction?
Reproduction not involving the fusion of gametes. Al, genetic material comes from one parent and the offspring are identical
What are identical copies made by asexual reproduction called?
Clones
What is sexual reproduction?
Involves fusion of gametes and mixing of genetic information
Why is variation important?
Gives offspring better chance of surviving difficult conditions
Why may there be differences in characteristics of individuals of the same species?
Different genes have been inherited
Conditions in which they developed
A combination of genetic and environmental causes
How may human development be affected during pregnancy?
If the mother
Smokes
Drinks alcohol
Baby may have a small birth weight
The weaker plants may have the ……. Genes as the healthier plants but cannot grow if deprived of ………
Same
Nutrients
What is good about cloning in plants?
Cheap
Effective
What is tissue culture?
Taking small groups of cells from a plant and growing them in special conditions
What is a quick cheap way of cloning plants?
Taking cuttings
What is used to clone animals?
Embryo transplants
Explain embryo transplanting
in this process an embryo with unspecialised cells is split into smaller groups of cells each group are genetically identical cells is transplanted and allowed to develop
Why is it more difficult to clone animals than plants?
Animal embryos must be split into groups of cells and then each group must be transplanted into a host mother. It takes longer for embryos to develop
What happens in adult cell cloning?
The nucleus of an adult cell replaces the nucleus of an egg cell
Explain adult cell cloning
The nucleus is removed from an unfertilised egg cell
The nucleus is removed from the adult cell and placed in the egg cell
The egg is given an electric shock which causes the cell to divide
The embryo is identical to the adult cell
Benefits of cell cloning
Development which have been engineered to produce valuable proteins in their milk which have uses in medicine
Cloning saves animals from extinction
Disadvantages of cell cloning
Concerns about ethics
Limits variation. Problems for natural selection
Concerns about using the technique in future
What is genetic engineering
Changing the genetic makeup of an organism
What is genetic engineering used for?
Transfer a gene from one organism to the other
How does genetic engineering work?
A gene is cut out of chromosomes using an enzyme. The gene is then placed. In the chromosome of another organism
