Looking Inside Cells Chapter 2 Section 4

Introduction Organelles Tiny structures that carry out specific functions within the cell Compare to organs in your body…

Cell Wall Rigid layer of nonliving material that surrounds the cells of PLANTS Function: helps to protect and support the cell Made of cellulose Animal cells DO NOT have cell walls

Cell Membrane In cells with cell walls, the cell membrane is located just inside the cell wall In other cells, the cell membrane forms an outside boundary Function: controls what substances come into and out of a cell

Parts of the Nucleus Nucleus Acts as the “brain” of the cell The cell’s control center, directs cell’s activities Nuclear envelope Nucleus is surrounded by this membrane Materials pass in and out of the nucleus through pores in this structure Chromatin Contains instructions that direct the functions of a cell Thin strands, contain genetic material Nucleolus Where ribosomes are made

The Nucleus

Organelles in the Cytoplasm The region between the cell membrane and the nucleus Clear, thick, gel-like fluid Many organelles are found in the cytoplasm

Mitochondria Convert energy in food molecules to energy the cell can use to carry out its functions “powerhouse”

Endoplasmic Reticulum Passageways carry proteins and other materials from one part of the cell to another Mail truck

Ribosomes Function as factories to produce proteins Sometimes attached to the endoplasmic reticulum or float in cytoplasm

Golgi Bodies Receive proteins and other newly formed materials from the endoplasmic reticulum, package them, and distribute them to other parts of the cell Mail room

Chloroplasts Capture energy from sunlight and use it to produce food for the cell Only in plant cells

Vacuoles Storage area of cells (food and other materials) Plants cells have ONE large vacuole Animal cells have many small vacuoles, or none at all

Lysosomes Small, round structures containing chemicals that break down certain materials in the cell “garbage truck”

Specialized Cells In many-celled organisms, the cell are often quite DIFFERENT from each other Cells are specialized to perform specific functions Cells ---- Tissues ---- Organs ---- Organ Systems