Cell Cycle, Mitosis, Meiosis, and Chromosomal Disorders

Comprehensive vocabulary flashcards covering the cell cycle, mitosis, meiosis, gametogenesis, chromosomal abnormalities, and cancer.

Cell Cycle

The sequence of events from the time a cell first arises as a result of cell division until the time when that cell divides.

Interphase

The 'resting stage' where the cell is not dividing, lasting for at least 90% of the cell cycle.

G1 phase

The first gap phase of interphase characterized by normal cell functions, cell growth, organelle duplication, and protein synthesis.

S phase

The synthesis stage of interphase during which DNA replication and histone synthesis occur.

G2 phase

The second gap phase of interphase involving protein synthesis and the replication of centrosomes (centrioles).

Apoptosis

Genetically programmed death of cells.

Mitosis

The nuclear division of somatic cells that produces two daughter cells genetically identical to the parent cell.

Prophase

The mitotic phase in which nucleolus and nuclear membrane disappear, chromosomes condense into sister chromatids connected at centromeres, centrosomes migrate, and spindle fibers form.

Metaphase

The mitotic phase during which spindle microtubules attach to centromeres and chromosomes align at the metaphase plate of the cell.

Anaphase

The mitotic phase in which centromeres split, sister chromatids separate, and chromosomes move toward opposite ends of the cell.

Telophase

The mitotic phase where chromosomes reach opposite poles, uncoil or decondense, nuclear envelopes form, nucleoli reappear, and spindle fibers disappear.

Cytokinesis

The division of cytoplasm to form two identical daughter cells, accomplished via a cleavage furrow in animal cells and a cell plate in plant cells.

Meiosis

The nuclear division of sex cells resulting in four unique haploid daughter cells, creating gametes and maintaining chromosome number across generations.

Synapsis

The pairing of homologous chromosomes to form a tetrad during prophase I of meiosis.

Spermatogenesis

The process of sperm production resulting in four haploid sperm cells from a diploid primary spermatocyte.

Oogenesis

The process of egg production resulting in one haploid ovum and three polar bodies from a diploid primary oocyte.

Aneuploidy

The gain or loss of whole chromosomes, which is the most common chromosomal abnormality caused by nondisjunction.

Nondisjunction

The failure of homologous chromosomes or sister chromatids to separate correctly during meiotic cell division.

Monosomy

A condition in which a zygote is missing one chromosome, which is lethal and prevents development to birth.

Trisomy

A condition in which a zygote possesses three copies of a chromosome, which is lethal except for chromosomes 13, 18, and 21.

Klinefelter's Syndrome

A chromosomal disorder characterized by XXY sex chromosomes in sterile males who may exhibit female physical characteristics.

XYY Syndrome

A chromosomal disorder involving an extra Y chromosome in males, who exhibit normal development, above-average height, and delayed mental maturation.

Metafemales

Females with XXX sex chromosomes who exhibit normal sexual characteristics, tall stature, and potential learning difficulties.

Down Syndrome

A genetic condition caused by Trisomy 21, resulting in mental retardation and physical defects such as heart disorders.

Turner's syndrome

A missing chromosome disorder (45, XO) in females lacking one X chromosome, characterized by short stature, webbed neck, underdeveloped ovaries, sterility, and mental retardation.

Cancer

A disease resulting from a malignant tumor characterized by abnormal cell growth, tissue invasion, and metastasis.