Please enable JavaScript.
Coggle requires JavaScript to display documents.
Genetic Diagrams - Coggle Diagram
Genetic Diagrams
-
-
Pedigree analysis
Doctors can use a pedigree analysis chart to show how genetic disorders are inherited in a family. They can use this to work out the probability that someone in a family will inherit a condition. A pedigree analysis is usually undertaken if families are referred to a genetic counsellor following the birth of an affected child.
The pedigree analysis chart is used to show the relationship within an extended family. Males are indicated by the square shape and females are represented by circles. Affected individuals are red and unaffected are blue. Horizontal lines between males and females show that they have produced children.
This analysis shows both male and female are affected, and every generation has affected individuals. There is one family group that has no affected parents or children, but the remaining two families have one affected parent and affected children too.
-
-
If the organism has two of the same alleles then it is known as homozygous- this can be dominant or recessive.
If the organism has two different alleles then this is known as heterozygous- here the dominant trait will be expressed.
- Chromosome- a long coiled up strand of DNA in the shape of an X
- Gene- a section of DNA that codes for a particular protein.
- Genome- the entirety of an organisms genes.
- Allele- the different version of the same gene.
- Dominant- occurs more often/ will be displayed over a recessive trait.
- Recessive- will only be displayed if there's two of it.
- Genotype- the biological expression of a trait/ the DNA of a trait.
- Phenotype- the physical expression of a characteristic.
- Gamete- a sex cell eg. sperm or egg.
- Zygote- fertilised egg cell.
Sex is determined at fertilisation because the sperm will carry either an X chromosome or a Y chromosome. The egg is always X. There is a 50% chance of it being a girl or a boy due to the sperm, what the sperm carries will determine the sex of the zygote. If it's XX then it's a girl and if it's XY then it's a boy. The chances of each can be shown here:
The inheritance of a single characteristic is called monohybrid inheritance. You can use different diagrams to show this such as punnett squares, genetic diagrams and pedigree diagrams.