Animal and Plant 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 energystore materialsbring materials in from environmentget rid of wastemove substances to where they are

neededreproduce

Cells

• There are 2 major types of cells:– Animal – Plant

Organelles

• “little organs”• Cells have specialized parts that carry out

specific functions• they all work together– Some are found ONLY in animal or ONLY in plant

cells

Lysosomes• Contain enzymes that can break down

molecules (ex. food brought in from outside cell or bacteria/viruses)

• They are like a garbage dump for the cell

Cytoplasm/ Cytosol

• 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)

on 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 moremitochondria

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

Golgi Apparatus• Several tubes- looks like a stack of flattened

balloons• Packages materials to be removed from cell• Secretes mucus

VesicleMembrane-covered sacs that transport/store materials in the cell. Also help waste exit the cell

Vacuoles• Membrane bound sacs filled with a watery

solution• In plant cells:– Much larger– Pressure against cell

membrane push it firmlyagainst 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 lysosomesSmall vacuoles Large vacuoles

No cell wall Cell wall No chloroplasts Chloroplasts Rounded shape Brick shaped

Lysosome

vacuole Ribosome

Nucleolus

Rough ER

Ribosomes

Smooth ER

Lysosome

Cell Diffusion for Growth

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

• 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

Cell Diffusion for Growth

• Osmosis– Diffusion of water across

the semi-permeable membrane dues to concentration differences

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

Purple circles = molecule