Unit 3: Biology Date:____________________

2.1 Plant and Animal Cells

Cell Theory

• States that:

– All living things are made up of one or more cells

– The cell is the smallest unit of life

– All cells come from other cells- they do not come from non-living matter

Cells are Alive!

• All cells have to perform the same basic activities to stay alive

• use energy

• store materials

• bring materials inside from environment

• get rid of waste

• move substances to where they are needed

• Reproduce

There are 2 major types of cells:

-Animal - Plant

Organelles:

• Cells have specialized parts (“little organs”) that carry out specific functions

• they all work together

Unit 3: Biology Date:____________________

Organelle Description PictureLysosome • Contain enzymes that can break down

molecules• They are like a garbage dump for the cell

Cytoplasm • Aqueous (water-based) solution inside the cell

• Organelles are suspended in here

Cell Membrane

• A thin, double layered film that separates the interior of the cell from the external environment

• Supports the cell and controls movement in and out of the cell (‘semi permeable’)

Nucleus • “control centre”- directs all cell’s activities• Contains the cell’s DNA (genetic

information) in chromosomes

Mitochondria • Produce energy for the cell via cellular respiration

• Have an inner and outer membrane• Cells that require lots of energy (ex. muscle

cells) will have more mitochondria

Endoplasmic Reticulum (ER)

• System of tubes and canals around the nucleus

Transport materials (ex. proteins and lipids through cell

Ribosomes • tiny, spherical balls that make cell’s proteins• Located in the cytoplasm but also attached

to the rough ER

Unit 3: Biology Date:____________________

Golgi Apparatus

• Several tubes- looks like a stack of flattened balloons

• Packages materials to be removed from cell• Secretes mucus

Vesicle • Membrane-covered sacs that transport/store materials in the cell.

• Also help waste exit the cell

Vacuoles • Membrane bound sacs filled with a watery solution

• Much larger in plant cells• Pressure against cell membrane push it

firmly against the cell wall- turgor pressure

Cell Wall • Plant cells only• Tough, rigid layer that surround cell- made

of cellulose• Provides support and structure

Chloroplasts • Contains all the chemicals (chlorophyll) for photosynthesis

• Have an inner and outer membrane• Looks like a stack of pancakes

Animal vs. Plant

ANIMAL PLANT

Lysosomes No lysosomes

Small vacuoles Large vacuoles

No cell wall Cell wall

No chloroplasts Chloroplasts

Rounded shape Brick shapedCell Diffusion for Growth

• materials must pass through the cell membrane to get in and out of the cell

Unit 3: Biology Date:____________________

• Diffusion: Chemicals move from an area of high concentration to low concentration

Why Diffusion?

• How chemicals move from organelle to organelle

• How oxygen gets delivered to your organs.

• How nerve cells communicate to each other

Osmosis

• Diffusion of water across the semi-permeable membrane dues to concentration differences

• water moves toward the most concentrated, away from the most dilute