Reproduction Flashcards
What happen in sexual reproduction?
The joining (fusion) of male and female gametes. The mixture of the genetic information from the two parents leads to variety I’m the offspring
What happen in asexual reproduction?
No fusion of the gametes takes place and only one individual is needed as the parent. There is no mixing of genetic information and so no genetic variation in the offspring (except from in mutation). These genetically individuals are known as clones
How can plants be produced quickly and cheaply?
By taking a cutting from older plants. These new plants are genetically identical to the parent plant
What are the moderne cloning techniques?
Tissue culture
Embryo transplant
Adult cloning
What is tissue cloning cloning?
Using small groups of cells from part of a plant
What is embryo transplant cloning?
Splitting apart cells from a developing animal embryo before the become specialised, then transplanting the identical embryos into host mothers
What is adult cell cloning?
The nucleus is removed form an unfertilised egg cell. The nucleus from the adult body cell, e.g. a skin cell, is then inserted into the egg cell. An electric shock then causes the egg cell to begin to divid to form embryo cells. These embryo cells contain the same genetic information as the adult skin cell. When the embryo has developed into a ball of cells, it is inserted into the womb of an adult female to continue its development
In genitc engineering, how can the genes be ‘cut out’ from the chromosomes of humans or other organisms?
By using enzymes and transferred to cells of other organisms
Where and when can genes be transferred to?
The cells in animals, plants or microorganism at early stages in their development so that they develop with the desired characteristics
What can be do with new genes?
They can be transferred to crop plants
Crop that have had their genes modified in this way are called genetically modified crops (GM crops)
What is an example of a genetically modified pant?
Ones that art resistant to insect attack or to herbicides
What do genetically modified crops generally show?
Increased yields
What are the concerns about genetically modified crops?
The effect on population of wild flowers and insects, and uncertainty about the effects of eating GM crops on the man health
What are the two types of reproduction?
Sexual reporduction
Asexual reproduction