Cell Cycle and Reproduction Quiz

Cell Cycle and Reproduction

• The cell cycle describes how cells grow, prepare for division, and become two new cells.
• This cycle ensures all cells have the same information.
• Four stages: G1, S, G2, and M.
• Errors in the cell cycle can cause uncontrolled growth (cancer).

Gap 1 (G1)

• Cell growth and protein/organelle production.
• Preparation to copy DNA.
• "Getting ready to work." phase.

Synthesis (S)

• DNA replicates.
• DNA contains instructions for cell function.

Gap 2 (G2)

• Further cell growth.
• Checks for errors in copied DNA.
• Prepares for cell division.
• Final check before cell splitting.

Mitosis (M)

• Cell divides to form two identical cells.
• Each new cell receives a full set of DNA.

Cell Structure and Organization

• Cells have organelles with specific functions.
• Nucleus: Controls cell activities; contains DNA.
  • Nucleolus: Makes ribosomes.
• Cytoplasm: Suspends organelles and enables chemical reactions.
• Cell Membrane: Controls what enters/exits the cell; phospholipid bilayer with proteins and carbohydrates.
• Cell Wall (plants only): Protects & provides rigidity; made of cellulose.
• Mitochondria: Produces energy (ATP).
• Chloroplast (plants only): Converts sunlight to sugar through photosynthesis.
• Ribosomes: Make proteins.
• Endoplasmic Reticulum (ER): Transports materials.
  • Rough ER: Makes proteins.
  • Smooth ER: Makes lipids; detoxifies harmful substances.
• Golgi Complex: Processes and packages proteins.
• Lysosomes: Break down waste and damaged cell parts.
• Vacuole: Stores food, nutrients, and waste. Larger in plant cells.
• Cytoskeleton: Provides structure, movement, and transport.

Cell Theory

• Robert Hooke coined the term "cell" (observed cork).
• Anton van Leeuwenhoek first observed living cells ("animalcules").
• Matthias Schleiden: All plants are made of cells.
• Cell theory statements:
  • All living things are composed of one or more cells.
  • The cell is the basic unit of structure and function.
  • All cells come from pre-existing cells.

Cellular Diversity

• Unicellular organisms: One cell; all life processes happen in one cell; small & simple; various environments (bacteria, amoeba, paramecium).
• Multicellular organisms: Many cells; cells specialized for varied tasks; work together (humans, animals, plants, fungi); larger and more complex.

Prokaryotic vs. Eukaryotic Cells

• Prokaryotic: Simple; no nucleus or membrane-bound organelles. (e.g., Bacteria, Archaea)
  • DNA floats freely.
• Eukaryotic: Complex; nucleus and membrane-bound organelles; (e.g., Animal cells, plant cells, fungal cells)
  • DNA is inside a nucleus.

Cellular Reproduction

• Mitosis (Asexual): Single cell divides into two identical daughter cells; for growth, repair, and asexual reproduction. Steps: Interphase, Prophase, Metaphase, Anaphase, Telophase, Cytokinesis.

• Meiosis (Sexual): Produces sex cells (sperm and egg); reduces chromosome number by half. Steps: Interphase, Meiosis I (Prophase I, Metaphase I, Anaphase I, Telophase I), Meiosis II (Prophase II, Metaphase II, Anaphase II, Telophase II).

Plant and Animal Cells

• Plant cells: Cell wall (cellulose); chloroplasts; larger vacuoles.
• Animal cells: No cell wall; no chloroplasts; smaller or no vacuoles; centrioles.

Compound Microscope

• Essential tool for viewing cells, bacteria, etc.
• Multiple lenses to magnify.
• Parts: Eyepiece, Objective Lenses, Stage, Stage Clips, Arm, Base, Coarse Adjustment Knob, Fine Adjustment Knob, Diaphragm, Condenser, Light Source.
• Total magnification = eyepiece magnification × objective lens magnification.

Test your knowledge on the cell cycle and its stages, including G1, S, G2, and M. This quiz explores cell division, DNA replication, and the importance of errors in this process. Understand how cells organize and function within their structure.