Biology: How Life Works - Chapter 11 Study Guide

A collection of vocabulary flashcards related to DNA replication, cell division, and cancer biology, based on key concepts from Biology: How Life Works Chapter 11.

DNA replication

The process by which DNA makes a copy of itself, featuring semi-conservative replication where each new DNA double helix contains one old strand and one new strand.

Semi-conservative replication

A method of DNA replication in which each of the two new DNA molecules contains one original strand and one newly synthesized strand.

Leading strand

The continuously synthesized strand during DNA replication that runs in the 5' to 3' direction.

Lagging strand

The discontinuously synthesized strand during DNA replication, built in short segments called Okazaki fragments.

Okazaki fragments

Short segments of DNA synthesized on the lagging strand during DNA replication.

Telomeres

Repeated DNA sequences at the ends of linear chromosomes that protect the chromosome from deterioration or fusion with neighboring chromosomes.

Cyclins and CDKs

Proteins that regulate the cell cycle; cyclins activate cyclin-dependent kinases (CDKs), which phosphorylate target proteins to drive the cycle forward.

p53

A tumor suppressor gene that plays a crucial role in controlling the cell cycle and preventing cancer.

Apoptosis

Programmed cell death that is a normal process for eliminating damaged or unwanted cells.

Tumor suppressor gene

Genes that slow down cell division, repair DNA mistakes, or tell cells when to die; mutations can lead to cancer.

Oncogenes

Genes that, when mutated or expressed at high levels, can lead to cancer by promoting cell division.

Somatic cell

Any cell of a living organism other than the reproductive cells, typically diploid (2n).

Gamete

A reproductive cell that is haploid (n), which can fuse with another gamete during fertilization.

Cytokinesis

The division of the cytoplasm of a cell, resulting in two daughter cells, usually occurring after mitosis.

Homologous chromosomes

Chromosome pairs, one from each parent, that are similar in shape and size and contain genes for the same traits.

Chromatin

The complex of DNA and proteins found in eukaryotic cells that organizes and compacts DNA for cell division.

Sister chromatids

Identical copies of a chromosome that are connected by a centromere during cell division.

Centromere

The region of a chromosome where the two sister chromatids are joined.

Centrosome

An organelle that serves as the main microtubule organizing center for the cell and plays a key role in cell division.

Centriole

A cylindrical structure involved in the development of spindle fibers in cell division.

Cell cycle checkpoints

Regulatory points in the cell cycle that monitor and control the progression of the cycle, ensuring proper division.

Binary fission

A form of asexual reproduction in prokaryotes where a single cell divides into two identical daughter cells.

Interphase

The phase of the cell cycle where a cell spends most of its life, preparing for cell division; includes G1, S, and G2 phases.

Nucleosome

A structural unit of a eukaryotic chromosome, consisting of a segment of DNA wound around a core of histone proteins.