Genetics Vocabulary Spring 2014 Venable Biology

The passing of traits from parents to offspring Genetics and Heredity The study of heredity The passing of traits from parents to offspring

Gamete – sex cell; examples are sperm, egg, pollen, ovule Meiosis / Gametes The making of sex cells Gamete – sex cell; examples are sperm, egg, pollen, ovule

A fertilized egg ; two gametes become one Zygote A fertilized egg ; two gametes become one

Fertilization / Pollination The fusing or uniting of two gametes (into 1 cell) ; forms a zygote or seed When pollen reaches the stigma of the female pistil of a flower

Stamen / Pistil Male reproductive part of the flower ; made of the anther (holds pollen) and filament Female reproductive of the flower ‘ made of the stigma (sticky top portion), style, and ovary

Strands of genetic information found in the nucleus of a cell Chromosomes Strands of genetic information found in the nucleus of a cell

Haploid / Diploid n; ½ the number of chromosomes than the normal body cell (somatic cell) ; number of chromosomes in the gametes of an organism ; ex. 23 in human 2n; two full sets of chromosomes in a normal body cell; ex. 46 in human

Allele An alternative form of a gene (one member of a pair) that is located at a specific position on a specific chromosome ; each for a particular trait For example, the gene for seed shape in pea plants exists in two forms, one form or allele for round seed shape (R) and the other for wrinkled seed shape (r).

Trait Characteristics inherited from two parents ; A genetically determined characteristic or condition

Genes An allele that codes for a particular trait ; Genes are segments of DNA located on chromosomes. Genes exist in alternative forms called alleles.

Genotype / Phenotype Gene combination that determines a trait ; the genetic makeup of an organism The physical trait created by the genotype ; an organism's expressed physical traits

Allele that is seen of present ; represented with a capital letter Dominant / Recessive Allele that is seen of present ; represented with a capital letter Allele that is masked / not seen unless paired with another recessive allele ; lower case letter Dominant Alleles: T, G, A, B Recessive Alleles: t, g, a b

“The Father of Genetics” Gregor Mendel Austrian monk who studied the garden pea plant (7 different traits studied); “The Father of Genetics”

Homozygous / Heterozygous Genotype were both alleles paired up are identical ; ex. TT, tt Genotype were both alleles paired up are opposite ; ex. Tt

Sex Chromosomes The 23rd pair of paired chromsomes in an human somatic cell (The 1-22 pair are referred to as AUTOSOMES). The sex chromsomes may be X or Y ; human males all have a 23rd pair that is XY, females are XX

Karyotype A visual map of all the chromsomes of a person / organism ; karyotyping is a test to examine chromosomes in a sample of cells, which can help identify genetic problems as the cause of a disorder or disease. This test can: Count the number of chromosomes Look for structural changes in chromosomes

Punnett Square Tool used in genetics to predict the outcome of two parents offspring ; a type of grid used to show the gametes of each parent and their possible offspring; a type of grid that can indicate all the possible outcomes of a genetic cross

Pedigree Tool used to show the passing of disorders within a family in genetics / it is an account of the descent of a person or family traced through a series of generations