Cell Division & DNA Processing Study Guide

This set of flashcards covers key concepts related to cell division and DNA processing, summarizing essential definitions and mechanisms.

Surface Area : Volume (SA:V) Ratio

As a cell gets larger, its volume grows faster than its surface area, affecting nutrient and waste exchange.

Cell Division Purposes

Growth, tissue repair, reproduction, and maintaining genome-to-cytoplasm ratio and favorable SA:V dynamics.

Binary Fission

Division process in prokaryotes where a single circular chromosome replicates, resulting in two genetically similar daughter cells.

Mitosis

Eukaryotic somatic cell division where one diploid parent cell divides into two genetically similar diploid daughter cells.

Meiosis

Specialized cell division resulting in four genetically diverse haploid gametes; includes two divisions: Meiosis I and Meiosis II.

Interphase

The preparation phase of the cell cycle consisting of G1, S, and G2 phases.

Mitosis Stages

Prophase, Prometaphase, Metaphase, Anaphase, Telophase, followed by Cytokinesis.

Cytokinesis in Animals vs Plants

Animal cells use a contractile ring to pinch in two; plant cells form a cell plate to develop a new cell wall.

Cell Cycle Regulators

Internal regulators (like cyclins) and external regulators (such as growth factors) control the timing of cell division.

Cell Cycle Checkpoints

Control mechanisms like G1/S, G2/M, and Spindle checkpoints monitor cell integrity and readiness to proceed through the cell cycle.

Benign Tumors

Localized, slow-growing tumors that are not invasive or metastatic.

Malignant Tumors

Invasive, genetically unstable tumors that can metastasize to other organs.

Telomeres

Repetitive DNA at chromosome ends that shorten with cell division, associated with replicative senescence.

Apoptosis

Programmed cell death involving mechanisms that eliminate damaged cells; regulated by proteins like Bcl-2 and caspases.

DNA Structure

DNA is a double helix made of two antiparallel polynucleotide strands with a sugar-phosphate backbone.

Base Pairing Rules

A pairs with T (2 hydrogen bonds) and G pairs with C (3 hydrogen bonds).

Nucleotide Structure

Nucleotides consist of a deoxyribose sugar, a phosphate group, and a nitrogenous base.

Semi-Conservative Replication

Each daughter DNA helix contains one parental and one newly synthesized strand; demonstrated by the Meselson–Stahl experiment.

Enzymes in DNA Replication

Key enzymes include helicase, DNA polymerase, primase, and ligase, essential for the DNA synthesis process.

DNA Replication Timing

In eukaryotes, replication occurs during the S phase of interphase; in prokaryotes, it coincides with binary fission.