Mitosis, Meiosis, and Mendelian Genetics

This flashcard set covers the vocabulary and core concepts of cell division (Mitosis and Meiosis) and Mendelian Genetics as presented in Lab 7.

Chromosomes

Coiled strands of DNA and protein that carry gene information.

Homologous Pairs

A pair of chromosomes, one from Mom and one from Dad, that contain the same genes but not necessarily identical alleles.

Diploid (2n)

Cells containing two copies of each chromosome; humans have 23 of these homologous pairs.

Karyotyping

A method used to determine if an individual has the correct number of chromosomes.

Haploid (1n)

Cells containing one copy of each chromosome (no pairs), typical of human sex cells.

Mitosis

The process of cell division every somatic cell goes through to make an exact copy of itself.

Somatic cells

General body cells that undergo mitosis.

Interphase

The phase between mitotic phases when DNA replicates; cells spend most of their time in this stage.

Sister Chromatids

Identical halves of a replicated chromosome connected by a centromere.

Centromere

The structure that connects two sister chromatids in a replicated chromosome.

Prophase

The stage of mitosis where the nuclear membrane breaks down and spindles (animal cells) or microtubules (plant cells) start to form.

Metaphase

The stage of mitosis where chromosomes line up along the metaphase plate (an imaginary plane).

Anaphase

The stage of mitosis where chromosomes break at centromeres and sister chromatids move to opposite ends of the cell.

Telophase

The mitotic stage where the nuclear membrane reforms, nucleoli reappear, replicated chromosomes arrive at poles, and chromosomes unwind into chromatin.

Cytokinesis

The final stage where the cell is cleaved in two via a cleavage furrow in animal cells or a cell plate in plant cells.

Meiosis

A special kind of division used to produce gametes with half the amount of DNA ($1n$), resulting in four non-paired cells.

Gametes

Eggs and sperm cells produced via meiosis.

Nondisjunction

An error that can occur during meiosis resulting in an incorrect distribution of chromosomes in eggs or sperm.

Alleles

Different versions of a gene, which can be dominant or recessive.

Homozygous Alleles

Two alleles for a gene that are the same (e.g., $AA$ or $aa$).

Heterozygous Alleles

Two alleles for a gene that are different (e.g., $Aa$).

Genotype

The genetic combination of alleles (e.g., $PP$, $Pp$, or $pp$).

Phenotype

The physical trait expressed by an organism, such as flower color.

Dominant Allele

An allele that dominates in a heterozygote and determines the phenotype.

Punnett Square

A genetic tool used to predict the probability of passing specific genetic information to offspring.