circulatory system 1-1a

Living Systems

Focus Question:

What do living organisms need to survive?

Lesson 1-1A

Needs of Living OrganismsWorld is full of living organisms

People are alive

Pets are alive

Trees, grass, flowers, and insects in the country are alive

Fish, whales, and kelp in the ocean are alive

Millions of tiny organisms living everywhere that are too small to see

Life is everywhere

Living organisms need things in order to stay alive.

What are some of the things that all organisms need?

Talk in your groups and make a list of needs shared by all organisms.

All living organisms need:

Water

Food

Gas exchange (inc. oxygen & carbon dioxide)

Waste disposal

AmoebaHave you ever heard of an amoeba?

Amoebae are organisms. But they are different from humans in many ways.

They are tiny. Need a microscope to see a single amoeba.

They live in water.

An amoeba is made of one cell

Amoeba is an example of a single-celled organisms. Most of the organisms on Earth are single-celled organisms.

AmoebaSingle-celled organisms live their whole lives surrounded by water.

Get food from the water around them.

Use gases dissolved in the water.

Eliminate their waste into the water around them.

They get everything they need for life directly from their watery environment.

Turn to page 85 in science textbook

AmoebaCell membrane surrounds the cell like skin.

Liquid cytoplasm fill the cell (mostly water)

ElodeaLeaf of water plant – seen through a microscope

Made of thousands of cells

Each cell looks like a green brick

Multicellular organismMade of more than one cell

Leaf is only two cells thick, so each cell is touching the water

Cell membrane surrounds the cell

Cytoplasm fills the cell

Green chloroplasts contain chlorophyll

Human Cell ChallengeHumans are multicellular organisms.

Don’t live in water

Made of trillions of cells

Most of the cells are deep inside our muscles, organs, and bones.

But, every cell is alive.

Every cell is receiving the resources it needs to survive

Food

Water

Gases

Waste Disposal

Human Cell ChallengeHow do human cells get the things they need to survive?

How do they get food?

How do they get water?

How do they get oxygen?

How do they get rid of waste?

Talk in your groups – share your ideas about the problem of providing for the needs of the cells

InvestigationThat beating is called a pulse

Result of blood being pushed through a blood vessel by the beating of your heart

Every time your heart beats, it pushes a pulse of blood through the blood vessels running through your body.

Why is blood being pumped through blood vessels all over your body?

Ideas -

Circulatory System

Open textbook to page 86

Pair/share reading

After reading – complete notebook sheet “Circulatory System Review”

Answer questions as best as you can before going back to the text to look up answers.

Modify our list of ideas, based on information from the reading.