Chapter 10: Sexual Reproduction & Genetics

Genes

DNA segments that are arranged on the chromosomes to control the production of proteins

Homologous Chromosomes

chromosomes that make up a pair, one chromosome from each parent

Gametes

Sex cells that have half the number of chromosomes.

haploid

A cell with "n" number of chromosomes.

fertilization

the process by which one haploid gamete combines with another haploid gamete. A cell will contain a total of 2n chromosomes as a result of fertilization.

diploid

A cell that contains 2n number of chromosomes

meiosis

A type of cell division that reduces the number of chromosomes; therefore it is referred to as the reduction division.

crossing over

the process during which chromosomal segements are exchanged between a pair of homologous chromosomes

genetics

the science of heredity.

homozygous

An organism w/ two traits of the same alleles for a particular trait

heterozygous

an organism with 2 different alleles for a particular trait

genotype

The organism's allele pairs (the letters).

phenotype

the observable characteristic or outward expression of an allele pair (physical trait).

law of segregation

Mendel's law states that 2 alleles for each trait separate during meiosis. During fertilization, 2 alleles for that trait unite.

hybrid

organism heterozygous for a specific trait.

law of independent assortment

States that a random distribution of alleles occurs during gamete formation. Genes on seperate chromosomes sort independtly during meiosis.

genetic recombination

the new combination of genes produced by crossing over and independent assortment

polyploidy

the occurence of one or more extra sets of all chromosomes in an organism

recessive

Mendel's name for a specific trait hidden or masked in the F1 generation

dominant

Mendel's name for a specific trait that appeared in the F1 generation

allele

alternative form that a single gene may have for a particular trait