Cell Reproduction, Senescence, and Death

Flashcards to review key concepts on cell reproduction, senescence, and death.

Cell Cycle

A series of phases that a cell goes through leading to its division and replication.

Cyclins

Regulatory proteins that control the progression of the cell cycle.

CDKs (Cyclin-Dependent Kinases)

Enzymes activated by cyclins to regulate the cell cycle.

Apoptosis

Programmed cell death that occurs in multicellular organisms.

Senescence

The process by which cells lose the ability to divide and grow.

Tumorigenesis

The process of forming a tumor, which may involve uncontrolled cell division.

Contact Inhibition

A mechanism that prevents cells from dividing when they come into contact with neighboring cells.

G1 Phase

The first phase of the cell cycle, characterized by high metabolic activity and growth.

S Phase

The phase of the cell cycle in which DNA replication occurs.

G2 Phase

The second gap phase of the cell cycle, where the cell prepares for mitosis.

M Phase

The phase of the cell cycle that includes mitosis and cytokinesis.

p53 Protein

A critical tumor suppressor protein that regulates the cell cycle and prevents cancer.

Telomeres

The end sections of chromosomes that protect them from deterioration.

Telomerase

An enzyme that extends the telomeres of chromosomes.

Checkpoint

Regulated transitions in the cell cycle that can block progression under certain conditions.

G1/S Checkpoint

The point in the cell cycle where cells commit to DNA synthesis.

G2/M Checkpoint

The checkpoint that ensures DNA is replicated before mitosis.

M/G1 Checkpoint

The checkpoint that ensures chromosomes are properly separated before cell division.

Cytokinesis

The division of the cytoplasm to form two separate daughter cells after mitosis.

Growth Factors

Extracellular signals that promote cell division and growth.

CDK Inhibitors

Proteins that inhibit the activity of cyclin-dependent kinases.

Ras Protein

A proto-oncogene involved in transmitting signals within cells, often mutated in cancers.

Oncosis

A type of cell death caused by severe cellular injury.

Necrosis

Uncontrolled cell death due to external factors such as infection or injury.

MAP Kinases

Enzymes that are part of signaling cascades regulating cellular processes.

E2F-1

A transcription factor that promotes the expression of genes required for DNA synthesis.

pRb (Retinoblastoma Protein)

A key regulator of the cell cycle that prevents excessive cell growth.

INK4 Family

A group of CDK inhibitors that include proteins like p15, p16, p18, and p19.

Cyclin A

A cyclin that plays a pivotal role in regulating the cell cycle during the S phase.

Cyclin D

A cyclin that is important for the G1 phase and the G1/S transition.

Cyclin E

A cyclin that is critical for the entry into the S phase.

Cdc2 (CDK1)

A cyclin-dependent kinase that is essential for the initiation of mitosis.

Spindle Checkpoint

A mechanism that prevents the separation of chromosomes until they are properly attached to the spindle.

Nucleus

The cellular structure containing the genetic material.

Cytosol

The fluid component inside cells, excluding organelles.

Transcription Factors

Proteins that help regulate the transcription of specific genes.

DNA Repair

The collection of processes by which a cell identifies and corrects damage to its DNA.

Hypoxia

A condition in which the body or a region of the body is deprived of an adequate oxygen supply.

Ubiquitin

A small protein that tags other proteins for degradation.

Tumor Suppressor Genes

Genes that protect a cell from one step on the path to cancer.

Cell Cycle Regulation

The mechanisms that control the progression of the cell cycle and prevent cancer.

Signal Transduction

The process by which cells respond to external signals.

Kinase

An enzyme that catalyzes the transfer of phosphate groups.

Cellular Response

The reaction of cells to signals from their environment.

Raf Kinase

A protein kinase that plays a crucial role in transmitting growth signals.

GAP

GTPase-activating protein, which stimulates the GTP hydrolysis by GTP-binding proteins.

Fibroblast Growth Factor (FGF)

A growth factor involved in angiogenesis, wound healing, and embryonic development.