Pages 34-42

Introduction (pages 34-35)

• Organelles- tiny cell structures that carry out specific functions within the cell

Cell Wall (page 35)

• A rigid layer of material surrounding plant cells and some bacterial cells
• Stiffness allows plants to grow very tall, but still allows water and nutrients to pass through 

Cell membrane (pages 35-36)

• All cells have cell membranes
• In cells without cell walls, this is the outer layer
• Controls what goes in and out of the cell

Nucleus (pages 36-37)

• The “brain” of the cell

Nuclear Membrane (page 36)

• Surrounds the nucleus
• Controls what goes in and out of the nucleus

      Chromatin (page 37)

• Strands of genetic material
• Directs the functions of the cell

Nucleolus (page 37)

• Structure within the nucleus that makes ribosomes

Organelles in the Cytoplasm (pages 37-41)

• Cytoplasm is a thick, clear, gel-like fluid
• Cytoplasm is in constant motion to transport materials 

Mitochondria (page 37)

• The “power-house” of the cell which produces energy needed by the cell

Endoplasmic Reticulum (page 40)

• Passageways that carry proteins from the ribosomes to the Golgi bodies

Ribosomes (page 40)

• Found on the outer surface of the endoplasmic reticulum and in the cytoplasm
• Produce proteins

Golgi Bodies (page 40)

• Flattened sacs and tubes
• Receive proteins from the endoplasmic reticulum, package them and pass them to the rest of the cell
• Also release materials to the outside of the cell

Chloroplasts (page 40)

• Found only in plant cells and some unicellular organisms
• Capture energy from the sun and use it to produce food for the cell

Vacuoles (page 41)

• The storage area of the cell for food, water or waste
• In plant cells, vacuoles often contain water, making the cell plump

Lysosomes (page 41)

• Small, round sacs that contain chemicals to break large food particles into smaller ones
• The lysosome’s membrane keeps the chemicals inside so the rest of the cell doesn’t get dissolved

Bacterial Cells (page 41)

• Bacterial cells have:
• cell wall
• cell membrane
• ribosomes
• genetic material that floats in the cytoplasm
• Bacterial cells do not have a nucleus
• Prokaryote- a cell without a nucleus
• Eukaryote- a cell with a nucleus

Specialized Cells (page 42)

• In multi-cellular organisms, cells are specialized
• Specialized cells carry out different functions (ex. bone cells vs. blood cells)
• Red blood cells, made in the bone marrow, carry oxygen to the cells
• White blood cells, also made in the bone marrow, fight diseases.
• Neurons, or nerve cells, carry messages though out the body.