Introduction to Cells

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.

Fill in the Blank

Name a type of cell

Examples of Cells

Amoeba Proteus

Plant Stem

Red Blood Cell

Nerve Cell

Bacteria

Two Types of Cells

•Prokaryotic
•Eukaryotic

Prokaryotic

• Do not have

structures
surrounded by
membranes

• Few internal

structures

• One-celled

organisms,
Bacteria

http://library.thinkquest.org/C004535/prokaryotic_cells.html

Eukaryotic

• 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

http://waynesword.palomar.edu/images/plant3.gif

“Typical” Plant Cell

Cell Parts

Organelles

Open Ended

Can you name any organelles?

Surrounding the Cell

Cell Membrane

• Outer membrane of cell

that controls movement
in and out of the cell

• Double layer

http://library.thinkquest.org/12413/structures.html

Cell Wall

• Most commonly found

in plant cells &
bacteria

• Supports & protects

cells

http://library.thinkquest.org/12413/structures.html

Inside the Cell

Nucleus

• Directs cell activities
• Separated from cytoplasm by nuclear

membrane

• Contains genetic material - DNA

Nuclear Membrane

• Surrounds nucleus
• Made of two layers
• Openings allow

material to enter and
leave nucleus

http://library.thinkquest.org/12413/structures.html

Chromosomes

• In nucleus
• Made of DNA
• Contain instructions

for traits &
characteristics

http://library.thinkquest.org/12413/structures.html

Nucleolus

• Inside nucleus
• Contains RNA to build

proteins

http://library.thinkquest.org/12413/structures.html

Cytoplasm

• Gel-like mixture
• Surrounded by cell membrane
• Contains hereditary material

Endoplasmic Reticulum

• Moves materials around

in cell

• Smooth type: lacks

ribosomes

• Rough type (pictured):

ribosomes embedded in
surface

http://library.thinkquest.org/12413/structures.html

Ribosomes

• Each cell contains

thousands

• Make proteins
• Found on ribosomes

& floating throughout
the cell

http://library.thinkquest.org/12413/structures.html

Mitochondria

• Produces energy through

chemical reactions –
breaking down fats &
carbohydrates

• Controls level of water and

other materials in cell

• Recycles and decomposes

proteins, fats, and
carbohydrates

http://library.thinkquest.org/12413/structures.html

Golgi Bodies

• Protein 'packaging

plant'

• Move materials within

the cell

• Move materials out of

the cell

http://library.thinkquest.org/12413/structures.html

Lysosome

• Digestive 'plant' for

proteins, fats, and
carbohydrates

• Transports undigested

material to cell
membrane for removal

• Cell breaks down if

lysosome explodes

http://library.thinkquest.org/12413/structures.html

Vacuoles

• Membrane-bound

sacs for storage,
digestion, and waste
removal

• Contains water

solution

• Help plants maintain

shape

http://library.thinkquest.org/12413/structures.html

Chloroplast

• Usually found in plant

cells

• Contains green

chlorophyll

• Where photosynthesis

takes place

http://library.thinkquest.org/12413/structures.html

Poll

How are you feeling about your knowledge of cells so far?

• I am an expert! Cell Master!

• I feel confident that I know some things

• I am unsure

• I am so lost