Biology

Front 1

diploid

Back 1

diploid number 2n=46 total number of chromosomes in a nucleus of each cell.

Front 2

activities associated with steps of meiosis

Back 2

meiosis reduces chromosome number to 1n, meiosis I; prophase I, homologues in synapsis (bivalents), crossing over occurs; metaphaseI, homologous pairs line up at equator;, anaphase, homologous pairs separate/split; telophase, homologous pairs reach opposite poles/division-end up with 2 cells; interkinesis; meiosis II; prophase II, no crossing over; metaphase II, middle; anaphase II, split; telophase II, divide; meiosis yields 4 haploid gametes (sperm cells)

Front 3

chromosomes

Back 3

structure consisting of DNA complexed with proteins that transmits genetic information from the previous generation of cells and organisms to the next generation.

Front 4

heterozygous, homozygous dominant and recessive

Back 4

heterozygous-possessing unlike alleles for a particular trait; homozygous dominant-possessing two identical alleles for a particular trait that is dominant; recessive-allele that exerts its phenotypic effect only in the homozygote, its expression is masked by a dominant allele.

Front 5

test cross

Back 5

cross between an individual with the dominant phenotype and an individual with the recessive phenotype. The resulting phenotypic ratio indicates whether the dominant phenotype is homozygous ro heterozygous.

Front 6

number of chromosomes in human gametes

Back 6

haploid sex cell contains 23 chromosomes

Front 7

G. Mendel

Back 7

Father of Genetics, discovered 2 laws governing inheritance 1. law of segregation and 2. law of independent assortment

Front 8

genotype and phenotype

Back 8

genotype-genetic makeup of an individual ex. Tt,tt, Tt; phenotype-outward appearance ex. short, tall, straight, curly

Front 9

karyotype

Back 9

tool which amounts to a picture of a person's chromosomes arranged in pairs according to their size, shape and general appearance in mitotic metaphase.

Front 10

nondisjunction

Back 10

Failure of homologous chromosomes or daughter chromosomes to separate during meiosis I and Meiosis II.

Front 11

incomplete dominance

Back 11

inheritance pattern in which th eoffspring has anintermediate phenotype, as when a red-flowered plant and a white-flowered plant produce pink-flowered offspring.

Front 12

codominance

Back 12

inheritance pattern in which both alleles of a gene are equally expressed.

Front 13

Tay Sachs disease

Back 13

is a disease that occurs in about one in 3,600 Jewish people that results from a lack of the enzyme hexosaminidase A and the subsequent storage of its substrate, a glycosphingolipid, in lysosomes.

Front 14

cystic fibrosis

Back 14

most common lethal genetic disease among Cuacasians in the United States, In these children, the mucus in the bronchial tubes and pancreatic ducts is particularly thick and viscous because the chloride ions fail to pass through plasma membrane channel proteins in the cells.