Unit 4 Extra Credit (AP Bio)

Cell Cycle

Cell cycle

the process through which cells replicate and make two new cells

Interphase

the crucial, longest phase of the cell cycle where a cell grows, carries out normal functions, and prepares for division by duplicating its DNA and organelles

G₁ Phase

the first stage of interphase in the eukaryotic cell cycle

S Phase

the part of interphase where DNA replication occurs

G₂ Phase

the final stage of interphase, where the cell grows, synthesizes proteins and organelles, and checks for DNA damage to prepare for successful cell division

Mitosis

the process where a single parent cell divides to produce two genetically identical daughter cells

Prophase

the first stage of mitosis (and meiosis), where the cell prepares for division by condensing duplicated DNA into visible chromosomes, forming the mitotic spindle to separate them, and beginning to break down the nuclear envelope

Metaphase

a crucial stage in cell division where condensed chromosomes, each consisting of two sister chromatids, align perfectly along the cell's equator, ensuring equal distribution to daughter cells

Anaphase

the stage in cell division where sister chromatids separate and move to opposite ends of the cell

Telophase

the final stage of nuclear division where two new nuclei form around the separated sets of chromosomes at opposite ends of the cell, the chromosomes uncoil back into chromatin, the spindle fibers disappear, and the nucleoli reappear

Cytokinesis

the final step in cell division where the cytoplasm splits, creating two separate, genetically identical daughter cells after mitosis or meiosis

G₀

a resting, non-proliferative state where cells exit the active cell cycle to perform normal functions or await signals, making them inactive in division but metabolically active with other cells

Proliferative

a stage where cells or tissues are actively multiplying

Non-proliferative

a stage where cells or tissues aren't actively multiplying

Chromosome

thread-like structure in cell nuclei, made of tightly coiled DNA and proteins that carry an organism's genes

Chromatid

one of two identical, duplicated strands of a chromosome, formed after DNA replication and joined at the centromere

Spindle apparatus

a crucial, dynamic microtubule structure that forms in dividing eukaryotic cells to meticulously separate duplicated chromosomes

Cyclin

regulatory proteins that control cell cycle progression by activating cyclin-dependent kinases (CDKs) at specific times

Cycin-dependent kinase

essential enzymes that control cell division and other crucial processes like transcription, metabolism, and apoptosis

Tumor suppressor

genes that regulate cell growth, division, and survival, acting as the "brakes" to prevent cells from becoming cancerous by slowing division, repairing DNA, and triggering cell death (apoptosis) when needed

Proto-oncogene/Oncogene

normal genes crucial for cell growth and division

Cancer

a group of diseases characterized by uncontrolled cell growth, invasion, and potential spread

Apoptosis

the body's controlled process for eliminating unneeded or damaged cells

Checkpoint

crucial control points that halt cell division until internal/external conditions are right, ensuring proper growth, DNA replication, and chromosome alignment to prevent errors like cancer, regulated by cyclins and CDKs

Mutation

a change in an organism's DNA sequence, occurring due to replication errors, mutagens (like radiation/chemicals), or viral infections, and can be passed down (germline) or affect only the individual (somatic)