Biology Lecture Flashcards

These flashcards cover key vocabulary terms from the biology lecture, focusing on genetics, inheritance, cell processes, and population genetics.

Allele

A variant form of a gene that can produce different traits.

Genotype

The genetic constitution of an individual; the pair of alleles for a given gene.

Phenotype

The observable physical or biochemical characteristics of an organism, determined by both genetic makeup and environmental influences.

Homozygous

Having two identical alleles for a particular gene.

Heterozygous

Having two different alleles for a particular gene.

Diploid

A cell or organism that has two sets of chromosomes, one from each parent.

Haploid

A cell or organism that has one set of chromosomes, typical of gametes.

Meiosis

The process of cell division that leads to the formation of gametes, reducing the chromosome number by half.

Spermatogenesis

The process of sperm cell development and maturation in males.

Oogenesis

The process of egg cell development and maturation in females.

Codominance

A form of inheritance where both alleles in a heterozygote are fully expressed, resulting in a phenotype that is neither dominant nor recessive.

Incomplete dominance

A form of inheritance where the phenotype of a heterozygote is intermediate between the phenotypes of the two homozygotes.

Polygenic inheritance

A form of inheritance in which multiple genes determine a phenotype.

Pleiotropy

The phenomenon where a single gene influences multiple phenotypic traits.

Linkage

The tendency of genes that are located close to each other on a chromosome to be inherited together.

Genetic drift

A random change in allele frequency in a population, often having a more significant effect in small populations.

Gene pool

The total collection of genes and alleles present in a population.

Tumor-suppressor genes

Genes that protect a cell from cancer by controlling cell division and repairing DNA.

Proto-oncogenes

Normal genes that, when mutated, have the potential to cause cancer.

Checkpoint

A control mechanism in the cell cycle that ensures the proper division of the cell.

Nondisjunction

The failure of homologous chromosomes or sister chromatids to separate properly during cell division, leading to an abnormal number of chromosomes.