A&P Seeley 3.4

Sex cells

The genes for a given trait

The expression of the genotype

Alternate forms of genes

If the two alleles for the trait are identical

If the two alleles for the trait are different

All the cells of the body except the gametes

The normal number of chromosomes in a somatic cell

The normal number of chromosomes in a gamete

Chromosome pairs

Each member of a homologous pair

Consists of all the genes found in the haploid number of chromosomes from one parent

A location on a chromosome where each gene of the genome occupies

Alleles exist in multiple forms

• aka mutated allele or polymorphism
• A different form of an allele

An autosomal recessive trait with multiple alleles

Two alleles at the same locus are expressed so that separate, distinguishable phenotypes occur at the same time

The dominant allele does not completely mask the effects of the recessive allele in the heterozygote

A disorder of a gene on chromosome 11

A homozygous recessive condition where two abnormal alleles are present and much lower than normal amount of b-globulin polypeptide chains are synthesized

A deficiency of hemoglobin in the blood

One normal allele and one abnormal allele are present

Results from the interaction of many genes

Traits affected by genes on the sex chromosome

Gametes are produced that have one homolog from each of the homologous pairs of chromosomes

Agents that cuase mutations