The excretory system2

The Excretory System Vocabulary

Foundation Science SC 22101

IMPORTANT: Nephrons and

Lacteals

LACTEAL inside villi, NOT nephrons

We will talk about nephrons when we talk about kindeysnext time.

The Excretory System

DigestiveSystem

The Excretory System

Excretory System

DigestiveSystem

Function of the Excretory System

1) To get waste and toxins out of body.

2) Helps keep the correct amount of water and ions in the body.

Function of the Excretory System

1) To get waste and toxins out of body.

2) Helps keep the correct amount of water and ions in the body.

An ion is an atom or molecule with a positive (+) or a negative (-) charge.

Homeostasis

Homeostasis is the body keeping stable.

If you have too much of something in your body, you will NOT be in homeostasis.

Your excretory system allows your body to stay in a state of homeostasis.

Osmoregulation

Osmoregulation is moving of ions across membranes to keep the right amount of water (=to keep homeostasis).

1) Hypotonic solutions are when there are many ions inside a cell, and water will go IN.

2) Isotonic solutions are when water will neither go in or out.

3) Hypertonic solutions are when there are many ions outside a cell, and water will go OUT.

Copy Diagram in Notebooks

Water will rush into the cell, making it swell (get bigger).

Water will rush OUT of the cell.

Don’t gain or lose water

Ions

Osmosis

Osmosis is water moving from an area of higher concentration to an area of lower concentration.

Testing – 1, 2, 3…..

A fish is swimming in saltwater. Which way will water want to move (in or out of the fish)?

A fish is swimming in saltwater. Which way will the fish’s water want to move? OUT

Would the saltwater be considered hypertonic or hypotonic?

Testing – 1, 2, 3…..

A fish is swimming in saltwater. Which way will water want to move (in or out of the fish)? OUT

Would the saltwater be considered hypertonic or hypotonic?

Testing – 1, 2, 3…..

A fish is swimming in FRESHWATER. Which way will the water want to move?

Testing – 1, 2, 3…..

Testing – 1, 2, 3…..

A fish is swimming in FRESHWATER. Which way will water want to move? INTO the fish

Would the freshwater be considered hypertonic or hypotonic?

A fish is swimming in FRESHWATER. Which way will water want to move? IN

Would the freshwater be considered hypertonic or hypotonic?

Testing – 1, 2, 3…..

1) What does “homeo” mean in Greek?

2) What does “hyper” mean in Greek?

3) What does “iso” mean in Greek?

4) Which one of our vocabulary words best describes what is happening when you wipe water off your body with a towel?

5) If you get into a bathtub filled with freshwater, is the water a hypertonic or hypotonic solution compared to your body (will water go into or out of your body)?

Questions

6) Do you think a saltwater fish would live if you put it into freshwater?

7) How do you think saltwater fish get the freshwater they need?

8) What is a semi-permeable membrane?