Cell Cycle and Division

Flashcards covering vocabulary related to the cell cycle and its regulation.

Cell Cycle

The series of events that take place in a cell leading to its division and duplication.

M phase

The phase of the cell cycle during which mitosis and cytokinesis occur.

Interphase

The longer phase of the cell cycle where the cell grows and DNA is replicated.

S phase

The part of interphase where DNA replication occurs.

Mitosis

The process of nuclear division in eukaryotic cells.

Cytokinesis

The process during which the cytoplasm of a parental cell is divided into two daughter cells.

Cyclin

A protein that regulates the cell cycle by activating cyclin-dependent kinases (Cdks).

Cdk (Cyclin-dependent kinase)

A family of protein kinases that are involved in regulating the cell cycle.

G1 phase

The first gap phase in interphase where the cell grows and synthesizes proteins before DNA replication.

G2 phase

The second gap phase in interphase where the cell prepares for mitosis.

Checkpoints

Regulatory points in the cell cycle where the cell can halt progression to fix errors or damage.

Apoptosis

Programmed cell death that occurs in multicellular organisms.

Cohesins

Proteins that hold sister chromatids together until they are ready to be separated during mitosis.

Condensins

Proteins that assist in packing DNA into chromosomes during mitosis.

Proteolysis

The breakdown of proteins into smaller polypeptides or amino acids.

Mitogen

A substance that stimulates cell division.

p53

A protein that regulates the cell cycle and functions as a tumor suppressor.

Rb (Retinoblastoma protein)

A protein that acts as a cell cycle regulator by inhibiting progression from G1 to S phase.

Cdc28

A cyclin-dependent kinase involved in cell cycle control in budding yeast.

Ubiquitin ligase

An enzyme that tags proteins with ubiquitin for degradation in the proteasome.

G1/S-Cdk complex

The complex that initiates progression from G1 to S phase, made of a cyclin and Cdk.

S-Cdk complex

The complex that promotes DNA replication during the S phase.

M-Cdk complex

The complex that triggers cell entry into mitosis.

What is the cell cycle?

The cell cycle is a series of regulated events that occur in a cell, leading to its division and duplication. It consists of four main phases: G1 (gap 1) phase where the cell grows and performs normal functions; S (synthesis) phase where DNA is replicated; G2 (gap 2) phase where the cell prepares for division; and M (mitosis) phase where the cell divides into two daughter cells. After the M phase, the cycle can repeat, or the cell may enter the G0 phase, where it exits the active cycle temporarily

What factors influence the regulation of the cell cycle?

Factors that influence the cell cycle include growth factors, nutrients availability, cell size, and DNA integrity.

How do growth factors affect the cell cycle?

Growth factors are signaling proteins that promote cell growth, division, and survival by activating specific cellular pathways.

What role do cyclins play in the cell cycle?

Cyclins are proteins that regulate the cell cycle by activating cyclin-dependent kinases (CDKs), which drive the progression through different phases of the cell cycle.

What is the function of cyclin-dependent kinases (CDKs)?

CDKs are enzymes that, when activated by cyclins, phosphorylate target proteins to advance the cell cycle.

What is apoptosis, and how does it relate to the cell cycle?

Apoptosis is programmed cell death that can occur if a cell detects irreparable damage during cell cycle checkpoints.

How does DNA damage checkpoint impact the cell cycle?

The DNA damage checkpoint halts the cell cycle, allowing for repair of damaged DNA or triggering apoptosis if repair is not possible.