Structure of the Cell

Introduction

• The cellular membrane defines the cell, separating it from the outside world.
• All cells contain DNA, the defining feature of living organisms.

Cell Types

• Eukaryotes: Have a nucleus (membrane around DNA)
  • Examples: Animals, plants, fungi
• Prokaryotes: No nucleus
  • Examples: Bacteria and Archaea

Eukaryotic Cell Structure

• Nucleus: Contains DNA in chromatin form.
  • Nucleolus: Dense area within the nucleus where ribosomal RNA is produced.
• Ribosomes: Translate mRNA into proteins. Composed of protein and RNA.
  • Locations: Can be free-floating or attached to the endoplasmic reticulum.

Endoplasmic Reticulum (ER)

• Rough ER: Has ribosomes attached, synthesizes proteins for membranes or secretion.
• Smooth ER: Lacks ribosomes, synthesizes lipids and hormones.

Golgi Apparatus

• Processes and packages proteins for transport within or outside of the cell.
• Proteins bud off the Golgi as vesicles.
  • Vesicles: Small, membrane-bound sacs for transporting substances.

Lysosomes and Vacuoles

• Lysosomes: Contain enzymes for digestion, mainly in animal cells.
• Vacuoles: Large vesicles for storage, similar to lysosomes in function.

Mitochondria and Chloroplasts

• Mitochondria: Powerhouse of the cell, converts sugars into ATP. Contains its own DNA.
• Chloroplasts: Site of photosynthesis in plant cells, also contains its own DNA.

Cell Wall and Cytoskeleton

• Cell Wall: Provides rigidity and strength, found in plant cells (made of cellulose).
• Microfilaments/Actin Filaments: Support the cell's shape and aid in movement.
• Centrioles: Assist with cell division, found in animal cells.

Summary

• Detailed overview of the cell structure.
• Key organelles and their functions within eukaryotic cells.