Unit 5 Vocabulary - Cell Division

DNA

The nucleic acid within a cell that contains instructions (genes) for cellular life

Gene

A section of DNA that codes for a specific trait

Chromosome

DNA condensed and wound up

Chromatid

One side of a chromosome that is identical to the other side - it has been replicated in preparation for cell division

Centromere

The portion of the chromosome in between the two chromatids

Nucleus

The organelle in eukaryotes that contains DNA

Somatic

relating to the body (somatic cells are all cells of the body other than reproductive cells)

Gamete

A reproductive cell, also known as a sex cell (sperm and egg cells)

Diploid

A cell that has a whole set of chromosomes, each of which are paired (23 pairs = 46 total in a human)

Haploid

A cell that contains only one set of chromosomes, unpaired (23 in humans)

Zygote

The fertilized egg cell - the first diploid cell that forms when two gametes (sperm and egg) meet in fertilization

Mitosis

The process where a single cell divides into two genetically identical cells - body cells (somatic cells) being made

Karyotype

An arrangement of a person’s chromosomes organized into homologous pairs

Homologous

identical - in terms of chromosomes, homologous pairs would be matching chromosomes that have identical genes that code for the same traits - one chromosome from mom, one from dad

Autosome

A chromosome that is not a sex chromosome (pairs 1-22)

Meiosis

The process where a single cell divides into four genetically unique cells with half the number of chromosomes of the parent cell - sex cells being made

Trisomy

A condition in which an extra copy of a chromosome is present in the cell nuclei, causing developmental abnormalities

Monosomy

A condition in which the cell nucleus is missing a copy of a chromosome, resulting in 45 chromosomes rather than the typical 46.

Duplication

A genetic mutation where a section of a chromosome is copied, resulting in an extra copy of that chromosomal region

Deletion

A genetic mutation where a chromosome has a missing segment of DNA.

Offspring

product of the reproductive process of humans, animals, and plants

Spermatogenesis

The production or development of mature sperm cells

Oogenesis

The production or development of mature egg cells

Nondisjunction

The failure of one or more pairs of chromosome pairs to separate normally during nuclear division

Sexual Reproduction

The production of new organisms by the combination of genetic information of two individuals of different sexes

Asexual Reproduction

A method of reproduction where a new individual is produced from a single parent, resulting in offspring that are genetically identical to the parent

Cytokinesis

The process by which the cytoplasm of a cell divides into two separate daughter cells

Stem Cell

Cells that can develop into many different types of cells in the body because they can access all of the DNA instructions

Cell Specialization

The process by which a cell develops specific structures and functions to perform a particular role within an organism

Cell Cycle

the series of events a cell undergoes as it grows, replicates its DNA, and eventually divides into two cells

Interphase

The resting phase between cell division, during which the cell grows, replicates its DNA, and prepares for cell division.

Cancer

uncontrolled cell division

Tumor

A mass of tissue that forms when cells grow and divide too much or don’t die when they should

Metastasis

The process by which cancer cells break away from the original tumor and spread to other parts of the body