Genes and Alleles

DNA definition

Contains the specific instructions that make each type of living creature unique

What are phenotypes?

the appearance of an organism based on its genotype plus environmental factor

What are alleles?

the different forms of a gene; could be dominant or recessive

What are genotypes?

the genetic makeup of an organism

What does this allele grouping tell us: TT

two dominant alleles (Homozygous)

What does this allele grouping tell us: tt

two recessive alleles (homozygous)

What is the definition of hybrid?

When an organism has one dominant allele and one recessive allele

What is the definition of purebread?

When an organism has two of the same alleles for a trait

How are genes and alleles related?

an allele is a variant form of a gene. For each gene, parents pass one one allele.

examples of phenotype

hair color, eye color, height

Who is Gregor Mendel?

father of genetics who worked with pea plants to learn the basic patterns of inheritance.

What is the nucleus?

A small egg shaped structure inside the cell that contains chromosomes and genes

Examples of genotypes

AA, Aa, aa

What are chromosomes?

Thread-like structures found in the nucleus of a cell that contains all DNA

What does this allele grouping tell us: Tt

a dominant and recessive allele, the offspring will show the dominant trait (heterozygous)

What is a gene?

a stretch of DNA on a chromosome with instructions for one trait

DNA stands for

deoxyribonucleic acid

What are recessive alleles?

variation of a gene that will not show up when other alleles are present

What are dominant alleles?

variation of a gene that will show up even when other alleles are present