Cell Biology Quiz

Prokaryotic Cells

Lack a nucleus and membrane-bound organelles.
Examples include Bacteria and Archaea.
DNA is found in a nucleoid region within the cell.
Simple structure features a plasma membrane, cell wall, and may have flagella or pili.
Generally smaller than eukaryotic cells.

Eukaryotic Cells

Contain a nucleus and membrane-bound organelles.
Examples include Animal cells, Plant cells, Fungal cells, and Protist cells.
DNA is contained within the nucleus.
Complex structure includes organelles such as mitochondria, endoplasmic reticulum, and Golgi apparatus.

Specific Cell Types

Animal Cells

Lack a cell wall, have irregular shapes, and often contain lysosomes and centrioles.
Key organelles include:
- Nucleus for storing genetic information.
- Mitochondria for ATP production.
- Endoplasmic Reticulum (ER) for protein (rough ER) and lipid (smooth ER) synthesis.
- Golgi Apparatus for modulating, sorting, and packaging proteins and lipids.
- Lysosomes for digesting macromolecules and cellular debris.

Plant Cells

Characterized by a rigid cell wall, chloroplasts, and a large central vacuole.
Key organelles include:
- Chloroplasts as the site for photosynthesis.
- Cell Wall for structural support and protection.
- Large Central Vacuole for maintaining turgor pressure and storing nutrients and waste products.

Fungal Cells

Similar to plant cells but have a cell wall made of chitin instead of cellulose.
Key organelles include:
- Nucleus for housing genetic material.
- Vacuoles for storing nutrients and waste.
- Cell Wall composed of chitin.

Protist Cells

A diverse group exhibiting characteristics of animal, plant, or fungal cells.
Notable examples:
- Amoebas: Unicellular and move using pseudopodia.
- Paramecia: Unicellular and move using cilia.
- Algae: Photosynthetic organisms with chloroplasts.

Specialized Cell Types

Specialized cells have unique structures and functions to perform specific roles within an organism, differing morphologically and biochemically from non-specialized cells.

Examples of Specialized Cells

Nerve Cells (Neurons)
- Function: Transmit electrical impulses throughout the nervous system.
- Structure includes axons (carry signals away), dendrites (receive signals), and synaptic terminals (release neurotransmitters).
Muscle Cells
- Function: Facilitate movement through contraction.
- Types include:
  - Skeletal Muscle Cells: Striated, voluntary, attached to bones.
  - Cardiac Muscle Cells: Striated, involuntary, found in the heart.
  - Smooth Muscle Cells: Non-striated, involuntary, located in internal organ walls.
Blood Cells
- Types:
  - Red Blood Cells (Erythrocytes) for carrying oxygen.
  - White Blood Cells (Leukocytes) for immune responses.
  - Platelets (Thrombocytes) for blood clotting.
Epithelial Cells
- Function: Form protective layers and barriers on surfaces and organs.
- Types include:
  - Squamous Epithelium: Thin, flat cells for skin and blood vessels.
  - Cuboidal Epithelium: Cube-shaped cells for ducts and glands.
  - Columnar Epithelium: Tall cells in the digestive tract for absorption and secretion.
Sperm Cells
- Function: Fertilize egg cells during reproduction.
- Structure includes:
  - Flagellum: Tail-like propelling structure.
  - Acrosome: Cap-like structure with enzymes to penetrate the egg.
Plant Cells
- Function: Perform photosynthesis and provide structural support.
- Specialized structures include:
  - Chloroplasts for capturing light energy.
  - Rigid Cell Wall for strength.
  - Central Vacuole for maintaining turgor pressure and nutrient storage.