Patterns of inheritance Flashcards
1
Q
What is chlorosis
A
When plant leaves appear yellow due to a lack of chlorophyll
2
Q
What are the environmental causes of chlorosis
A
- Lack of light
- Mineral deficiencies (iron and magnesium)
- Viral infections
3
Q
Genotype vs Phenotype
A
- Genotype= the genetic make up of an organism
- Phenotype= the observable characteristics of an organism
4
Q
Homozygous vs heterozygous
A
- homo= 2 identical alleles, either homozygous recessive or homozygous dominant
- hetero= 2 different alleles for a characteristic, dominant allele expressed
5
Q
Genes coding for continuous and discontinuous variation
A
- continuous controlled by many genes= polygenes
- discontinuous controlled by 1 or 2 genes
5
Q
What is monogenic inheritance
A
- the inheritance of a single gene
- shown in punnet squares
6
Q
What is co-dominance, how is it written
A
-2 alleles are equally dominant, both expressed in the phenotype
- 1 letter to represent genes, other letters at top right to represent alleles
7
Q
What alleles are dominant and recessive for blood group
A
- A and B are co-dominant
- O is recessive
8
Q
What are sex linked genes
A
- characteristics that are determines by genes carried on the sex chromosomes
9
Q
Cause, symptoms of haemophilia
A
- sex linked genetic disorder
- blood clots too slowly
- caused by an absence of protein blood clotting factor VIII
- affects males only- inherit the recessive, faulty allele and no dominant one as only 1 X chromosome
10
Q
What is dihybrid inheritance
A
- shows the inheritance of 2 genes on the same chromosome
11
Q
Expected ratio of dihybrid inheritance
A
9:3:3:1
12
Q
What is linkage
A
- when different genes are located on the same chromosome
13
Q
What is autosomal linkage
A
- when genes that are linked are found on 1 of the other pairs of chromosomes
14
Q
What is a recombinant offspring
A
- organisms have different combinations of alleles to both their parents
