7Unit 2: Cells

Students will understand that the organs in an organism are made of cells that have structures & perform specific life functions

Vocabulary

Cell

Tissue

Organ

System

Cytoplasm

Nucleus

Osmosis

Diffusion

Membrane

Chloroplast

Cell wall

Lysosome

Endoplasmic Reticulum

Vacuole

Mitochondria

Ribosomes

Cells

How big are cells?

What is in a cell?

How are these tiny things responsible for life functions? What is it they actually do?

Are there cells with specific functions which differ from other cells?

Cells Are Awesome!

Cells Are Make of Organelles

Organelles

“Little organs”

Specialized, work together to make cell work as a whole

Organelles

Cell wall

Cell membrane

Nuclear membrane

Nucleus

Nucleolus

Mitochondria

Endoplasmic reticulum

Ribosomes

Golgi bodies

Chloroplasts

Vacuoles

Lysosomes

Cytoplasm

Plant Cells vs. Animal Cells

Different Shape Plant cells are usually

rectangular

Animal cells do not have a definite shape

Plant Cells vs. Animal Cells

Different Structures

Plant Cell

Cell wall

Chloroplast

Large vacuole

Animal Cell

No cell wall

Lysosomes

No chloroplast

Bacteria vs Plant & Animal

What makes bacterial cells different from plant or animal cells?

Size – bacteria are much smaller

Nucleus – bacteria don’t have one

Some bacteria have a cell wall

Prokaryotic vs. Eukaryotic

Prokaryotic-no nucleusBacteria

Eukaryotic-nucleusPlants, animals,

fungi

Organelles

Make a chart in your notes about organelles. List the organelles, what it does, and if it is in a plant and/or animal cell.

Cell Wall

Provides support and protection

Allows water, carbon dioxide, and oxygen to pass in and out of cell

Only in plant cells

Cell Wall

Cell Membrane Supports and protects cell

Controls what goes in and out of cell

In both plant and animal cells

Surrounds the outside of animal cells

Inside cell wall in plant cellsCell Membrane

Nucleus

Brain of cell, controls cell’s activities

In plant and animal cells

Nucleus

Nuclear membrane

Protects nucleus

Controls what moves in and out of nucleus

In plant and animal cells

Nucleolus

Contains the chromosomes, which contain DNA

Plant and animal cells

Mitochondria

Breaks down sugar molecules into energy

“mighty mitochondria makes energy”

Plant and animal cells

Endoplasmic Reticulum

Carries materials through cell

Plant and animal cells

Ribosomes

Produces proteins

Plant and animal cells

Ribosomes

Vacuole

Stores food, water, and wastes

Plants have large vacuoles

Animals have small vacuoles

Chloroplasts

Contains chlorophyll

Uses carbon dioxide, water and light energy from the sun to create food for the plant

Photosynthesis

Only in plants

Lysosomes

Breaks down food and wastes

In animal cells, sometimes in plant cells

Organelles

On pg 20, draw a plant cell and an animal cell.

Be sure to include all the organelles listed

List the name and function of the organelles

COLOR IT (30 pts)

Specialized Cells

Are all the cells in our body, or another animal’s body, identical? Do they all do the exact same thing?

In multi-celled organisms, cells are most likely organized into tissues

Those tissues are organized into organs

Those organs are organized into systems

Organelles Cells Tissues Organs Systems Organism

Examples

Nucleus

Nerve Cell

Nervous Tissue

Brain

Nervous System

Human

Examples

Mitochondria

Muscle Cell

Muscle Tissue

Bicep Muscle

Muscular System

Carmelo Anthony

Movement In & Out

How do substances move into and out of a cell?

Diffusion is the movement of particles (tiny) into and out of a cell based on the “gradient”

The “gradient” means that particles travel FROM and high concentration TO a low concentration

Movement In & Out

High salt (NaCl)

Low salt

Osmosis

Diffusion or movement of WATER from an area of high concentration to an area of low concentration.

WATER ONLY

Vital to life and all living things

Active Transport

Movement of particles too large to use diffusion or osmosis

Requires assistance to get in or out

May require energy from the cell

Against the gradient

Movement In & Out

Osmosis is the diffusion of water into or out of a cell (think water-logged versus dehydration)Low water

Lots of water

Cells on the Computer

Go to: http://www.schools.utah.gov/curr/sci/secondary/7thGradeWebResources.htm

Explore through the last 7-8 activities. Some links are broken, just move to another one.

Cell Review

http://www.cellsalive.com/cells/cell_model.htm

Complete the following review questions from your book:

Pg 24: 1, 2, 4 (think back to characteristics of bacteria)

Pg 37: 1, 2

Pgs 39-41: 1-3, 5-10, 11-12, 15-17, 19, 20, 24-26