Year 8 Science · Unit 1 · Lesson 6
Foundation Worksheet
Learning Goals
True or False? Fix the false ones
Circle T or F for each statement. If the statement is false, rewrite it correctly on the line below.
Single-celled organisms such as amoeba need a circulatory system to supply their cells with oxygen.
Correct it:
As an organism grows larger, its surface area : volume ratio decreases, which is why large animals need transport systems.
Correct it:
Diffusion alone is too slow to supply oxygen to all the cells of a large organism like a blue whale without a transport system.
Correct it:
All multicellular organisms use exactly the same type of transport system to move substances around their bodies.
Correct it:
Match each substance to its source and destination
Draw a line connecting each substance on the left to the correct source → destination description on the right. Or write the matching letter.
| Substance | Your answer | Source → Destination |
|---|---|---|
| Oxygen | A. Produced by cells during metabolism → removed by kidneys and excreted as urine | |
| Carbon dioxide | B. Absorbed in the small intestine → delivered to all body cells | |
| Glucose | C. Breathed in at the lungs → delivered to every cell in the body | |
| Water | D. Made in the liver from protein breakdown → carried to kidneys for excretion | |
| Urea | E. Absorbed from food and drink → delivered to cells, tissues and organs throughout the body | |
| Carbon dioxide (plant) | F. Produced in cells during cellular respiration → carried to lungs and breathed out |
1. Explain why a single-celled amoeba living in a pond does not need a circulatory system, but a saltwater crocodile does. Use the terms diffusion, surface area and internal cells in your answer.
2. Name three substances that must be transported in the human body. For each one, state whether it is being transported to cells or away from cells.
Wrap Up
In one sentence, what was the main idea of this lesson?