Cell Structure & Function http://koning.ecsu.ctstateu.edu/cell/cell.html

Cell Theory All living things are made up of cells. Cells are the smallest working units of all living things. All cells come from preexisting cells through cell division.

Definition of Cell A Cell is the smallest unit that is capable of performing life functions.

Examples of Cells Amoeba Proteus Plant Stem Bacteria Red Blood Cell Nerve Cell

Prokaryotic Eukaryotic Two Types of Cells Prokaryotic Eukaryotic

Prokaryotic Cells Do not have structures surrounded by membranes Few internal structures One-celled organisms, Bacteria http://library.thinkquest.org/C004535/prokaryotic_cells.html

Eukaryotic Cells Contain organelles surrounded by membranes Most living organisms Plant Animal http://library.thinkquest.org/C004535/eukaryotic_cells.html

“Typical” Animal Cell http://web.jjay.cuny.edu/~acarpi/NSC/images/cell.gif

“Typical” Plant Cell http://waynesword.palomar.edu/images/plant3.gif

Cell Organelles

Cell Organelles Organelle= “little organ” Found inside eukaryotic cells ONLY

Cell Membrane Double layered boundary of the cell Outer membrane of cell that: holds the cell together controls movement in and out of the cell Found in both Plant and Animal Cells Key Term: Semi-permeable Acts like a filter or screen - some things pass through, others cannot

Cell Wall Found in Plant and Bacterial cells Rigid, protective barrier Located outside of the cell membrane This is an actual microscopic image. Colors are added digitally to enhance the different parts.

Cytoplasm Gel-like fluid that fills the cell Surrounded by cell membrane Constantly moving around the cell Contains all of the cell’s organelles

Nucleus Control Center of the Cell Contains DNA The easiest organelle to see under a microscope Usually one per cell

Mitochondria “Powerhouse of the cell” Makes Energy for the cell through the process of Cellular Respiration Has its own type of DNA

Chloroplast Found only in plant cells Contains the green pigment chlorophyll The place where Photosynthesis is performed. Site of food/sugar (glucose) production

Vacuoles Large central vacuole usually in plant cells Many smaller vacuoles in animal cells Storage container for water, food, enzymes, wastes, pigments, etc.

Endoplasmic Reticulum A.k.a. “ER” Transports materials throughout the cell “Highway of the cell” 2 Types: Rough ER: studded with ribosomes; it makes proteins Smooth ER: does not have ribosomes

Quick Review Which organelle is the control center of the cell? Which organelle holds the cell together? Which organelles are not found in animal cells? Which organelle helps plant cells make food? What does E.R. stand for?

Enjoy these photos and diagrams of the cell organelles!

This bacteria cell has no membrane-bound nucleus but has a CELL WALL

ER!

…the Cell Wall

The green bubbles are the Chloroplasts filled with Chlorophyll

Mitochondria!

The nucleus with other structures…