Chapter 10:Inheritance Flashcards
What are the two types of chromosomes on which genes occur?
Autosomes (non-sex) chromosome and sex chromosomes
How do inherited genes occur?
Single autosomal gene inheritance
What is single autosomal gene inheritance?
In diploid cells, alleles occur in pairs. One chromosome is inherited from the female parent via egg and the other via sperm from the male parent. The alleles dominance determines to phenotype expressed. Figure 10.1.2
What is parental generation (P)?
The two parental organisms breed in experiment
What is first filial generation (F1)?
The first generation of offspring produced from (P)
What is incomplete dominance?
When an organism had a different phenotype of its purebred parents as one gene is not dominant over the other.
What is codominant?
When both genotypes are fully expressed e.g. cattle having a mixture of black and white
What is sex-linked inheritance?
A gene located on a sex chromosome
How does sex-linked inheritance occur?
In diploid organisms where the chromosomes are hemizygous (only a single copy of a gene)
How does sex-linked inheritance affect offspring?
Figure 10.1.9
What is X-linked recessive?
A phenotypical expression determined by a recessive allele on the x-chromosome
When can a female express the gene?
When both x-chromosomes have the gene, otherwise they are a carrier
What is x-linked dominance?
A phenotypical expression determined by a dominant allele on the x-chromosome
When can a female express an x-linked dominance allele?
Always, but males expressing the gene cannot pass to their sons.
What is multiple allelic inheritance?
When three or more alleles are present. figure 10.1.10
