7th gr Science

Heredity

The passing of traits from parent to offspring

egg

Female sex cell

self-pollination

The transfer of pollen from one flower to another flower on the same plant.

mutation

any change in the DNA of a gene or chromosome

RNA

carries the codes for making proteins

The genetic traits are located in the

chromosomes

Mendel found that two genetic factors --one from the sperm cell and one from the egg cell

control each trait.

genotype

the two alleles that control the phenotype of a trait

incomplete dominance

when the offspring's phenotype is a combination of the parents' phenotypes

Punnett Square

a model used to predict possible genotypes and phenotypes of offspring

gene

a section on a chromosome that has genetic information for one trait

pedigree

A chart or "family tree" that tracks which members of a family have a particular trait

codominance

A condition in which both alleles for a gene are fully expressed

heterozygous

An organism that has two different alleles for a trait

homozygous

An organism that has two identical alleles for a trait

Genetics

The study of how traits are passed from parent to offspring

alleles

Different forms of a gene

sperm

Male sex cell

hybrid

Offspring of crosses between parents with different traits

DNA

a complex molecule that contains the code for an organism's genetic information

dominant trait

a genetic factor that blocks another genetic factor

recessive trait

a genetic factor that is blocked by the presence of a dominant factor

In polygenic inheritance, traits are determined by

more than one gene and have many possible phenotypes.

cross-pollination

occurs between flowers of two different plants

polygenic inheritance

occurs when multiple genes determine the phenotype of a trait

phenotype

physical expressions of the gene. like brown or curly

Mendel

scientist who studied pea plants to figure out genetic information that applies to all organisms

Mendel's experiments with pea plants showed

that some traits are dominant and others are recessive

An organism's nucleotide sequence can change through

the deletion, insertion, or substitution of nitrogen bases.

Geneticists use Punnett Squares to predict

the possible genotypes and phenotypes of offspring.