Ch. 11 Study Guide

Surface Area and Volume

• Surface Area: Total area of the cell's outer membrane.

• Volume: Space inside the cell (where organelles are located).

• As Cell Size Changes:

  • As a cell grows larger, both surface area and volume increase, but volume grows faster.

  • This leads to a decrease in the SA:Vol ratio, making it harder for the cell to exchange nutrients and waste efficiently.

• Impact on Survival:

  • A smaller SA:Vol ratio can limit the cell’s ability to sustain itself, potentially leading to division or cell death.

Asexual vs. Sexual Reproduction

• Asexual Reproduction:

  • Produces identical offspring from one parent.

  • Advantages: Fast, energy-efficient.

  • Example: Bacteria (binary fission).

• Sexual Reproduction:

  • Offspring result from two parents combining genetic material.

  • Advantages: Genetic diversity, adaptability.

  • Example: Humans, flowering plants.

Chromosome Structure and Cell Division

• Prokaryote Chromosome: Circular and simpler.

• Eukaryote Chromosome: Linear, tightly coiled around proteins (histones).

• Role in Cell Division: Chromosomes carry genetic information that is replicated and distributed to daughter cells.

Cell Cycle in Prokaryotes vs. Eukaryotes

• Prokaryotes: Simple binary fission.

• Eukaryotes: Complex cycle (G1, S, G2, M phases) involving DNA replication and mitosis.

Eukaryotic Cell Cycle & Mitosis

• Phases:

  • G1: Cell growth.

  • S: DNA replication.

  • G2: Preparation for mitosis.

  • M (Mitosis): Division of nucleus.

• Mitosis Stages:

  • Prophase, Metaphase, Anaphase, Telophase.

Cytokinesis

• Animal Cells: Cleavage furrow forms.

• Plant Cells: Cell plate develops due to the rigid cell wall.

Regulation of the Cell Cycle

• Growth Factors: Signal cells to divide.

• Cyclin and MPF: Proteins that ensure timing and order of cycle progression.

Cancer

• Definition: Uncontrolled cell division forming tumors.

• Treatments: Surgery, radiation, chemotherapy, immunotherapy.