Cell Cycle, Mitosis, and Regulation Flashcards

A set of vocabulary flashcards reviewing the cell cycle, phases of mitosis, chromosome terminology, regulatory proteins, tumor suppressors, and cancer therapeutics based on the lecture notes.

Centrioles

Cellular structures made up of microtubules that are duplicated in the G2 phase and form the mitotic spindle during prophase.

Cell cycle

The summary of events that occur throughout a cell's lifetime, from 'birth' until the passing of the cell or cell replication.

Interphase

The longest phase of the cell cycle where the cell spends most of its time growing, metabolizing, performing normal cell functions, and preparing for cell division.

Mitotic phase

The phase of the cell cycle during which cell replication occurs.

Apoptosis

Programmed cell death where a cell sacrifices itself if it fails cell cycle checkpoints.

G1 phase

The stage of interphase where the cell grows, makes organelles and proteins, and performs normal cell functions.

S phase

The stage of interphase where DNA replication occurs so that new cells have DNA identical to the old cells.

G2 phase

The stage of interphase involving additional growth, synthesis of organelles and proteins, duplication of centrioles, and final preparation for division.

G0 phase

A state reserved for special cells, such as muscle and nerve cells, where they remain without replicating.

Quiescent cells

Cells that remain in a non-dividing state and do not replicate.

Labile cells

Cells that are continuously capable of replication, such as skin cells.

Mitosis

The process of taking two sets of DNA and dividing them so each new cell receives a set of DNA.

Cytokinesis

The division of the cytoplasm, organelles, and proteins, and creation of new cell membranes to produce distinct new cells.

Prophase

The first phase of mitosis where chromatin condenses into chromosomes (sister chromatids), the nuclear envelope fragments, the nucleolus disappears, and centrioles form the mitotic spindle.

Chromatin

Uncondensed DNA arranged like 'beads on a string' that winds up into condensed chromosomes during prophase.

Sister chromatids

Duplicated chromosomes produced for mitosis.

Metaphase

The phase of mitosis where the mitotic spindle attaches to chromatids at the centromere and chromatids align along the cell's equator.

Centromere

The central region of chromatids where the mitotic spindle attaches during metaphase.

Anaphase

The phase of mitosis in which the spindle pulls chromatids apart to opposite poles of the cell.

Telophase

The phase of mitosis that reverses prophase: chromatids decondense into chromatin, the nucleolus reappears, and the nuclear envelope reforms.

Somatic cells

General body cells that undergo mitosis and contain 46 chromosomes (23 from mom and 23 from dad).

Gametes

Sex cells (egg and sperm) containing 23 chromosomes that result in 4 unique daughter cells.

Diploid

Cell state having 2 sets of chromosomes (46 total in human somatic cells).

Haploid

Cell state having 1 set of chromosomes (23 total in human gametes).

Cyclin-dependent kinase (CDK)

An enzyme that adds phosphate groups ($\text{PO}_4^{3-}$) to molecules to help regulate the cell cycle.

Cyclin D

A regulatory protein produced in response to growth factors that binds to CDK4 to help cells exit interphase.

pRb (Retinoblastoma protein)

A tumor suppressor protein and regulator of cell division that, once activated by CDK4, allows the cell to leave G1 phase and enter S phase.

p53

A tumor suppressor protein that scans DNA for errors before replication, inducing p21 production when errors occur or promoting apoptosis if errors cannot be fixed.

p21

A tumor suppressor protein induced by p53 that prevents cells from leaving G1 phase by blocking cyclin-CDK4 and pRb activation.

TP53 gene

The gene encoding the p53 protein; frequent mutations lead to loss of p53 function and allow abnormal cells to proceed through the cell cycle.

Benign tumor

A slow-growing, localized, encapsulated tissue growth that does not spread.

Malignant tumor

A fast-growing, irregular tumor that metastasizes and spreads to other parts of the body.

Angiogenesis

The creation of new blood vessels, controlled by p53 and utilized by cancer cells to acquire nutrients and oxygen.

Radiation therapy

A localized, non-specific cancer treatment that damages DNA and disrupts cell membranes of both cancer and normal body cells in the targeted area.

Chemotherapy

A systemically administered cancer treatment that specifically targets actively dividing cells (spindle cells) and affects labile cells.