AQA GCSE Biology B1.6 Genetic Variation and its control

Katie Nunn
Mind Map by Katie Nunn, updated more than 1 year ago
Katie Nunn
Created by Katie Nunn over 5 years ago


GCSE Biology Mind Map on AQA GCSE Biology B1.6 Genetic Variation and its control, created by Katie Nunn on 12/02/2014.

Resource summary

AQA GCSE Biology B1.6 Genetic Variation and its control
1 Inheritance
1.1 The information that results in plants and animals having similar characteristics to their parents is carried by genes, which are passed on in gametes from which the offspring develop
1.1.1 The nucleus of a cell contains chromosomes. The chromosomes carry the genes that control the characteristics of the body. Different genes control the development of different characteristics of an organism Differences in the characteristics of individuals of the same kind may be due to differences in: The genes that they have inherited The conditions in which they have developed or a combination of both
2 Reproduction
2.1 There are 2 forms of reproduction:
2.1.1 Sexual Reproduction~ the fusing of male and female gametes The mixture of the genetic information from two parents leads to variation in the offspring This is important for survival as some characteristics may give offspring a better chance of survival.
2.1.2 Asexual reproduction ~ no fusion of gametes and only one individual is needed as the parent There is no mixing of genetic information and so there is no variety in offspring. These genetically identical individuals are known as clones
3 Cloning
3.1 Modern cloning techniques include:
3.1.1 Tissue Culture ~ Taking small groups of cells from a part of a plant and growing them under special conditions. Taking cuttings from older plants and growing them. Embryo transplants ~ An embryo with unspecialised cells is split into smaller groups of cells, then the identical embryos are transplanted into host mothers. Adult cell cloning The nucleus of an adult cell e.g a skin cell is removed. The nucleus from an unfertilised egg cell (ovum) is removed The nucleus from the adult body cell is inserted into the empty ovum A small electric shock causes the egg cell to begin to divide to form an embryo The embryo cells contain the same genetic info as the adult skin cell (as its nucleus was used) When the embryo has developed into a ball of cells it is placed into the womb of an adult female to continue its development Dolly the sheep was produced by adult cell cloning in 1997 Benefits of it are: Could produce genetically engineered cloned animals to have valuable proteins in their milk. These have uses in medicine. Could be used to save animals from extinction Disadvantages of it are: Concerns about the ethics of it Cloning limits the variation in a population (limits the gene pool) Could cause problems for natural selection if the environment changes Concerned about using the technique to clone humans in the future
4 Genetic Engineering
4.1 Involves changing the genetic makeup of an organism
4.1.1 In genetic engineering genes from humans and other organisms are 'cut out' using enzymes. The gene is then placed in the chromosome of another organism. Genes can also be transferred into the cells of animals, plants or microorganisms in an early sate of development so that they develop with desired characteristics New genes can be transferred to crop plants. Crops that have their genes modified in this way are called Genetically modified crops (GM crops) GM crops may be insect or herbicide-resistant and usually have increased yields.
Show full summary Hide full summary


Biology B1.1 - Genes
B1.1.1 Diet and Exercise Flash Cards
Using GoConqr to study science
Sarah Egan
Biology AQA 3.1.3 Osmosis and Diffusion
Biology- Genes, Chromosomes and DNA
Laura Perry
Biology- Genes and Variation
Laura Perry
Biology AQA 3.1.3 Cells
GCSE AQA Biology 1 Quiz
Lilac Potato
Biology AQA 3.2.5 Mitosis
GCSE AQA Biology - Unit 2
James Jolliffe
Enzymes and Respiration
I Turner