Plant Cell: Structure and Function

Cell Types

• Prokaryotic Cells
• Eukaryotic Cells
  • Plant Cells: A type of eukaryotic cell and the functional unit of plants.

Plant Cell Components and Functions

Cell Wall

• Functions as a support skeleton and shapes the cell.
• Acts as a barrier against fungi infections.
• Composed of cellulose and other complex polysaccharides and proteins.
• Withstands high osmotic pressure.

Plasma Membrane

• Made of lipids; selectively permeable.
• Regulates nutrient and mineral transport.

Cytoplasm

• Contains cytosol, cytoskeleton, and organelles.

Nucleus

• Stores most genetic information (DNA).
• Key processes: DNA replication and RNA transcription.
• Nucleolus: Located inside the nucleus. Produces and assembles ribosomes.

Endoplasmic Reticulum (ER)

• Rough ER: Coated with ribosomes, involved in protein synthesis and modification.
• Smooth ER: Involved in protein modification and lipid synthesis.

Ribosomes

• Present on the rough ER and freely in the cytoplasm.

Golgi Apparatus

• Transports, sorts, and packages proteins from the rough ER.
• Modifies proteins (e.g., glycosylation).
• Synthesizes polysaccharides for the cell wall.

Chloroplasts

• Contain chlorophyll; site of photosynthesis.
• Convert sunlight, water, and CO2 into sugars and oxygen (byproduct).

Amyloplast

• Stores starch, an important polysaccharide.

Mitochondria

• Provide energy for biochemical reactions.

Peroxisomes

• Accumulate and degrade peroxides (e.g., hydrogen peroxide).

Vacuole

• Can occupy up to 90% of cell volume.
• Maintains turgor pressure and stability.
• Digests cellular waste.

Cytoskeleton

• Composed of microtubules and actin filaments.
• Maintains cell shape and organizes organelle movement.

Conclusion

• Overview of plant cell structure and functions.
• Mention of further resources for learning about animal cells.