Term | Definition |
Gametes | special cells used in sexual reproduction |
somatic cell | all diploid cells that are not gametes |
zygote | fertilized eggs formed form the joining of the gametes |
prophase1 | chromatin makes copy of itself & begins to coil up |
metaphase 1 | homologous pairs of chromosomes line up together at the miidle of the cell |
Anaphase 1 | homologous chromosomes move to opposite end |
telophase 1 | spindle fiber disappear & cell divides from cytokinesis |
Prophase 2 | centriole doubles
spindle fiber forms |
metaphase 2 | chromosomes line in middle |
Anaphase 2 | Individual chromatids move to opposite ends |
Telophase 2 | -2 daughter cells divides into 4 new daughter cells
-each new daughter cell has 23 chromosomes
-this is 1/2 the number of original parent cell |
phenotype | observable characteristic of an individual resulting from the interaction of its genotype with the environment |
genotype | an organisms allele pairs |
haploid | cell with half the number of chromosomes (n) as a diploid (2n) cell |
fertilization | process by which haploid gametes combine , forming a diploid cell with 2n chromosomes , with n chromosomes from the female parent and n chromosomes from the male parent |
diploid | having two copies of each chromosome (2n) |
meiosis | reduction division process ,occurring only in reproductive cells , in which on diploid cell produce 4 haploid cells that are not genetically identical |
crossing over | exchange of chromosomal segments between a pair of homologous chromosomes during propase 1 of meiosis |
genetics | science of heredity |
allele | alternative form that a single gene may have for a particular trait |
dominant | Mendel's name for a specific trait that appeared in the F1 generation |
recessive | Mendel's name for a specific trait hidden or masked in the F1 generation |
homozygous | organism with two of the same alleles for a specific trait |
heterozygous | organism with two of different alleles for a specific trait |
law of segregation | Mendel's law stating that two alleles for each trait separate during meiosis |
hybrid | organism heterozygous for a specific trait |
law of independent assortment | Mendel's law stating that a random distribution of alleles occurs during the formation of gametes |
genetic recombination | new combination of genes produces by crossing over and independent assortment |
polyploidy | having one or more extra set of all chromosomes |
somatic stem cells | found throughout the body during development, they multiply to replenish dying cells and replace damage tissue |
stem cells | unspecialized cells that are characteristically of the same family type |