Genetics Flashcards
What does autosomal recessive mean?
A genetic condition can occur when the child inherits ONE copy of a mutates gene from EACH parent
What does autosomal dominant mean?
ONE copy of a mutated gene from ONE parent can cause the genetic condition
What is co-dominance in relation to the ABO blood group?
Both A and B are dominant in relation to O
A can have the genotype AA or AO
B can have BB or BO
An O allele is recessive to both A and B
What is meiosis?
Final step in gamete production
Involves 2 distinct cell divisions
Produces 4 daughter cells with half the number of chromosomes of the parent cell
What is mitosis?
A type of cell division that results in 2 daughter cells each having the same number and kind of chromosomes at the parents nucleus
The daughter cells are clones of each other
What is the difference between mitosis and meiosis?
Mitosis - cell division which produces 2 identical, diploid body cells
Meiosis - form of division which produces 4 non-identical, haploid sex cells or gametes
What is an allele?
Different version of the same gene.
What does homozygous mean?
2 identical forms of the gene
What does heterozygous mean?
2 different forms of the gene
Examples: one normal allele and one mutated allele or 2 different mutated alleles
What is a locus?
The site or location of a specific gene on a chromosome
What is a genotype?
The arrangement of alleles that are to do with a certain trait
Examples: PP, Pp, pp
What is a phenotype?
An organisms observable characteristic - height, hair colour
What is co-dominance?
Both alleles show dominance
Example: people with AB blood type have one A allele and one B allele and both alleles are expressed at the same time
What are homologous chromosomes?
2 chromosomes in a pair - normally one inherited from the mother and one from the father
What is a mutation?
A change in 1 or more genes
