Genetics and Oogenesis

Flashcards for exam review.

Gene

Sum of all genes.

Allele

Alternate forms of a gene.

Genotype

Genetic makeup (all the genes) of an individual.

Phenotype

Physical characteristics of an individual (e.g., height, color, hair type, inherited disease).

Dominant Allele

Expressed by a capital letter; the gene expresses itself.

Recessive Allele

Expressed by a lowercase letter; the gene fails to express itself in the presence of a dominant allele.

TT

Tall (example of homozygous dominant).

Tt

Tall (example of heterozygous dominant).

tt

Short (example of homozygous recessive).

Oogenesis

The creation of an ovum.

First Stop in Oogenesis

Prophase I

Second Stop in Oogenesis

Metaphase II, triggered by fertilization.

Oogonium

Diploid germ cell (2n=46).

Primary Oocyte

Diploid cell (2n=46).

Secondary Oocyte

Haploid cell (n=23) destined to become the egg.

Polar Bodies

Byproducts of meiosis in oogenesis; they disintegrate.

Egg

Haploid cell (n=23).

Zygote

Diploid cell (2n=46) formed after the sperm nucleus enters the egg.