CSU Life 102 Chapter 14-Genetics

What is a phenotype?

Expression of alleles

Who described the laws of inheritance?

Mendel

What is a polygenic trait?

Multiple genes causing a phenotype

If a couple is homozygous recessive for one trait can the offspring have a dominant phenotype for that trait?

No

Phenotype

Physical appearance

Epistasis

When a gene @ one locus alters the phenotypic expression of a gene @ a second locus

How can a trait skip a generation?

When alleles are recessive but still in the gene pool

Pleiotrophy

When genes have multiple phenotypic effects

Complete Dominance

When phenotypes of heterozygotes and dominant homozygote are identical

What is a genotype?

Alleles of individual carriers

Pedigree

A family tree

What is a pleiotropic trait?

A gene causing many phenotypes

Sickle Cell Disease

A genetic disorder caused by substitution of a single amino acid in hemoglobin protein in RBCs

Genotype

Actual genes

Quantative Characters

Characters that vary in population along a continuum

What is heterozygous?

Different alleles for the same genes

Mendel discovered basic principles of heredity by breeding...

Garden peas

3 reasons humans aren't good subjects for genetic research

Generation time is too long, parents produce few offspring and breeding experiments are unacceptable

What do tests for identifying carriers do?

Help people make educated decisions about reproducing

What are the laws that came from Mendel's work?

Segregation, Independent Assortment, Dominance

3 Advantages of using garden peas

Short generation time, large numbers of offspring, mating could be controlled

Incomplete Dominance

The property of being expressed or inherited as a semidominant gene or trait