Inheritance
Explains what you need to know for Biology 1 section 3 for for your exam.
- Created by: Owain
- Created on: 02-01-13 17:31
View mindmap
- Inheritance
- Chromosomes
- Made up of DNA
- DNA carries the code for putting the amino acids together in a protein
- Different proteins give organisms different characteristics
- DNA carries the code for putting the amino acids together in a protein
- Genes
- Made up of DNA
- DNA carries the code for putting the amino acids together in a protein
- Different proteins give organisms different characteristics
- DNA carries the code for putting the amino acids together in a protein
- Genes have different forms called ALLELES
- Found in pairs inside the nucleus
- Made up of DNA
- Found in pairs inside the nucleus
- Made up of DNA
- Genetic terms
- Genotype - This is the combination of alleles that an organism has.
- Phenotype - The appearance of an organism caused by a gene
- Allele
- Genes have different forms called ALLELES
- Homozygous - This is where 2 of the same allele has joined
- Recessive - This is the allele that does not show itself in the organism unless there are 2 of them
- Heterozygous - This is where 2 different alleles have joined
- Dominant - This is the allele that shows itself in the organisms
- Gametes
- Sex cells - sperm and egg
- Contains one allele of each gene
- They only recieve half the number of chromosomes
- When fertilisation occurs two gametes join to form a zygote with a full number of chromosomes and two alleles
- Contains one allele of each gene
- When fertilisation occurs two gametes join to form a zygote with a full number of chromosomes and two alleles
- Gregor Mendel
- His work
- Used large numbers of pea plants in his experiments
- He recorded his observations carefully
- He repeated his experiment many times
- He analyzed his results using statistics
- deducted that characteristics are passed from generation to generation by factors passed on in gametes
- Published his work in1866 and sent it to many universities but it was not recognised
- His work was rediscovered in the early 20th century and scientists started to replicate his work
- His work
- Genetic modification
- This means taking genes and putting them into another organism and putting them in another organism
- Herbicide resistant soya beans
- Herbicide = Weedkiller
- Herbicide resistant = Not killed by herbicides
- Why? = Can spray a whole field and it will only kill weeds
- Advantages
- Less competition for space and nutrients
- Soya beans grow bigger
- Bigger yield
- More food
- More income for farmer
- Disadvantages
- Genes could be passed on to wild plants and they could become resistant to the herbicide
- Long term effects on enviroment is unknown
- Long term effects on human health unknown
- Trials = Large scale trials to check for effect on human health
- How?
- DNA of soya plant cut open
- Gene for herbicide resistance put into DNA of soya plant
- Gene for herbicide resistance cut out of DNA of plant not killed by herbicide
- Chromosomes
Comments
No comments have yet been made