Biology Chapter: Cell Structures

Cell Structures and Functions

• Cell Membrane: A phospholipid bilayer that regulates the entry and exit of substances in and out of the cell.
• Cell Wall: Rigid outer layer made of cellulose, providing support and protection for plant cells.
• Large Central Vacuoles: Storage organelles that serve as a source of water for plant cells.
• Chloroplast: Organelles where photosynthesis occurs, producing oxygen and glucose; exclusive to plant cells.
• Ribosomes: Small structures responsible for protein synthesis.
• Mitochondria: Known as the powerhouse of the cell, these organelles generate ATP through cellular respiration.
• Golgi Body: Functions like a post office, packaging materials for transport within the cell.

Organelles and Their Purposes

• Nucleus: Acts as the control center of the cell, housing DNA and regulating cell activities.
• Nuclear Membrane: Protects the nucleus and regulates the movement of materials in and out.
• Cytoplasm: Jellylike substance where organelles are suspended and cellular processes occur.
• Endoplasmic Reticulum (ER): Network of membranes acting as the cell's transportation system, moving materials around.
• Lysosome: Contains enzymes that break down waste and cellular debris.
• Vacuoles: Store various substances such as water, salts, proteins, and carbohydrates.

Biological Organization

• Tissue: A group of similar cells working together to perform a specific function.
• Organ: Structure consisting of different tissues coordinated to perform specific tasks.
• Organ System: Group of organs working collaboratively to perform vital bodily functions.
• Organism: Any individual living entity capable of independent life.
• Population: Group of the same species living in a defined area at the same time.
• Community: Assemblage of different species populations interacting in a specific area.
• Ecosystem: The interaction of a community with the abiotic elements (non-living) of the environment.

Key Processes

• Cellular Respiration: The process in mitochondria that converts glucose into ATP for energy use.
• Photosynthesis: Occurs in chloroplasts, where sunlight energy is converted into chemical energy (glucose).