Biology Cell Structure Complete Summary – Exam Revision Notes

Biology Cell Structure Complete Summary
Exam-Focused Revision Notes


1. Cell Theory
The Cell Theory states:
1. All living organisms are made of cells
2. Cells are the basic unit of life
3. All cells come from pre-existing cells
Scientists:
• Robert Hooke — discovered cells
• Matthias Schleiden — plants made of cells
• Theodor Schwann — animals made of cells


2. Types of Cells
Prokaryotic Cells
• No nucleus
• Smaller and simpler
• DNA floats freely
• Example: bacteria
Eukaryotic Cells
• Have nucleus
• Larger and more complex
• Contain membrane-bound organelles
• Example: plant and animal cells


3. Animal Cell Organelles

, Nucleus
• Controls cell activities
• Contains DNA
Cell Membrane
• Controls movement in and out of cell
• Selectively permeable
Cytoplasm
• Jelly-like substance
• Site of chemical reactions
Mitochondria
• Site of aerobic respiration
• Produces ATP energy
Ribosomes
• Site of protein synthesis
Endoplasmic Reticulum (ER)
Rough ER
• Has ribosomes
• Makes proteins
Smooth ER
• Makes lipids
• Detoxification
Golgi Apparatus
• Modifies and packages proteins
Lysosomes
• Contain digestive enzymes