Biology: Cell Cycle, Mitosis, and Cancer Review

Flashcards covering the stages of sexual reproduction, the cell cycle, detailed phases of mitosis, cytokinesis differences, cell cycle regulation, and the characteristics of cancer cells based on lecture notes.

Sexual reproduction

Increases biodiversity by combining genetic material from two parents, resulting in offspring with unique genetic combinations.

G1 phase (Gap 1)

Phase where the cell grows, performs normal functions, accumulates materials, and checks if environment conditions are suitable for DNA replication.

S phase (Synthesis)

The phase of the cell cycle where DNA replication occurs and chromosomes are duplicated.

G2 phase (Gap 2)

Phase where the cell continues to grow, synthesizes proteins, and prepares for mitosis by checking duplicated chromosomes for errors.

M phase

Includes mitosis (nuclear division) and cytokinesis (division of the cytoplasm).

Prophase

The longest phase of mitosis where chromatin condenses into visible chromosomes, the nuclear envelope breaks down, and the mitotic spindle begins to form.

Prometaphase

Phase where the nuclear envelope fully dissolves and spindle fibers attach to the kinetochores of the chromosomes.

Metaphase

Phase where chromosomes align at the equatorial plane called the metaphase plate and are attached to spindle fibers from opposite poles.

Anaphase

The shortest phase of mitosis where sister chromatids are pulled apart toward opposite poles as the centromeres split.

Telophase

Phase where chromatids reach the poles and de-condense into chromatin while the nuclear envelope reforms around each set of chromosomes.

Cytokinesis

The process of the cytoplasm dividing to form two daughter cells.

Cleavage furrow

An indentation formed in animal cells during cytokinesis, aided by a contractile ring of actin filaments that pinches the cell membrane.

Cell plate

A structure that forms in the middle of a plant cell during cytokinesis which eventually develops into a new cell wall.

G1 Checkpoint

Checks for sufficient nutrients, growth signals, and intact DNA to ensure the cell is ready for the S phase.

G2 Checkpoint

Ensures DNA has been completely replicated and checks for any DNA damage before the cell moves into mitosis.

M Checkpoint

Verifies that chromosomes are correctly aligned on the metaphase plate and that spindle fibers are attached properly before anaphase.

p53

Known as the "guardian of the genome," it halts the cell cycle for DNA damage repair or initiates apoptosis if damage is irreparable.

Apoptosis

A planned cell death that occurs when there are abnormalities, such as DNA damage or viral infection, helping to prevent the spread of cancer.

Proto-oncogenes

Genes that promote cell division and act as "on switches"; they can become cancer-causing oncogenes when mutated.

Cyclins

Proteins that regulate the progression of the cell cycle by activating Cdks.

Tumor Suppressor Genes

Genes like p53 and p27 that prevent uncontrolled cell division by acting as "off switches."

Metastasis

The process by which cancer cells spread from the primary tumor to distant parts of the body to form secondary tumors.

Histone

A group of proteins that form the nucleosome structure of a eukaryotic chromatin.

Nucleosome

A unit made up of DNA in a eukaryotic nucleus that looks like a string of beads.

Chromatin

The network of DNA strands and proteins in the nucleus of the cell.

Chromosome

The structure that sends genetic material from one parent to the child cell.

Chromatid

one of the two identical halves of a replicated chromosome

Centriole

The cell structure that organizes the mitotic spindle during animal cell division.

Centrosome

The microtubule organizes the center of cells

Centromere

The constricted region on a chromosome that ensures accurate separation of chromosomes.

Kinetochore

The assembly of proteins that attaches to the centromere of a chromosome.

Stem cell

A cell that continues to be able to divide and is needed to repair injuries, such as red bone marrow stem cells.

Binary Fission

The division of prokaryotic cells where the cell separates with a cell wall and plasma membrane to form two daughter cells.