Cell Boundries

What separates the inside from the outside?

Plasma Membrane (p 196)
A flexible boundary that controls what enters and exits the cell.

Cell Wall (p 196)
An additional boundry outside the cell wall which provides support for the cell.

What type of organism would have a cell wall?

What Fills A Cell?

Cytoplasm (p 199)
A clear fluid that is outside the nucleus and inside the plasma membrane.

This fluid is a bit thinner than toothpaste gel.

Cell Control

Nucleus (p 195)
The largest organelle in the cell, which contains DNA and controls the cell functions.

Nucleolus (p198)
Found in the nucleus and produces tiny particles called ribosomes which are involved in the making of proteins.

These two structures are enclosed in a nuclear envelope which has pores to allow material to pass back and forth.

Functions of Various Organelles:
Assembly of Material

Ribosome (p 198)
Assembles proteins for the cell.

Endoplasmic Reticulum (p 199)
A folded system of proteins that provides a site for chemical reactions and chemical synthesis.
Serves as a reaction "workbench."

Functions of Various Organelles:
Storage

Golgi Apperatus (p 200)
Stores and refines proteins for latter use by the plasma membrane and other organelles.

Vacuoles (p 200)
Stores food, water, or waste from the cell.
Special vacuoles expel water in one cell organisms.

Functions of Various Organelles:
Storage Cont.

Lysosome (p 201)
The cell’s "recycling center."
Lysosomes contain digestive enzymes that break down unwanted things and release new building materials.

Functions of Various Organelles:
Energy

Mitochondria (p 201)
The "batteries" of the cell.
A mitochondria stores energy by producing energy storing molecules.

Functions of Various Organelles:
Energy

Chloroplasts (p 202)
Transform light to energy into chemical energy in "green plant" cells.

Chloroplasts contain a molecule called cholophyll (p 202), this traps light and gives plants their green color.

Energy is stored as sugars and starches.

Plastids (p 202)
Storage organelles in plants.

Structures For Support

Cytoskeleton (p 203)
A network of thin elements that support a cell like a tent.

Microtubules (p 203)
Thin hollow cylinders of protein.

Microfilaments (p 203)
Thin solid protein fibers.

Structures For Locomotion

Cilia (p 204)
Numerous hair-like projections that beat in a wave to move a cell.
Picture "The Wave" in a stadium.

Flagella (p 204)
Longer projections that move with a whip like a motion.

These structures have many functions.

Cell Organization

From Small to Large

Unicellular

Multicellular

Tissues

Organs

Organ Systems