a protein that acts as a biological catalyst

the optimal internal temperature of our body, which is about 37°C

the regulation of the internal conditions to maintain optimum conditions for enzyme action and all cell functions

effectors and effects that work against each other

The importance of maintaining constant conditions in the body

Combined science

Effect of osmosis and sugar concentration on the mass of plant tissue: practical

Effect of osmosis and sugar concentration on the mass of plant tissue: analysis

Pupils will learn about factors that affect the rate of photosynthesis in plants, including temperature, light intensity and carbon dioxide concentration.

Pupils learned how substances essential for chemical reactions, and the products of the reactions, are transported into, around and out of plants, and about factors affecting the rate of water uptake by a plant.

This unit covers the importance of maintaining a constant internal environment, focusing on body temperature control, osmotic balance, and kidney function. It explains the roles of the skin, kidneys, and ADH, and emphasises data extraction, experiment techniques, and accurate data interpretation.

Coordination and control: maintaining a constant internal environment

The maintenance of a constant internal environment is known as {{}}.

True or false? All enzymes work optimally at pH 7 and 37 °C.

What name is given to enzymes whose active site has changed shape and no longer fits to its substrate?

A temperature receptor detects an increase in temperature.

A signal is sent to the coordination centre e.g. brain.

The coordination centre sends a message to the sweat glands.

Order the statements below to describe how the body responds to an increase in body temperature.

Jacob: You need to stay hydrated so that you can urinate.

Laura: We need water for chemical reactions to take place.

Sam: If you become severely dehydrated you can die.

Lucas: The kidneys control the amount of water lost through urination.

The Oak pupils are discussing the control of water levels in the body. Who is correct?

insulin which decreases blood sugar, and glucagon which increases blood sugar

thyroid stimulating hormone which increases the production of thyroxine

sweating to cool the body down, and shivering to warm the body up

the brain sending signals down a relay neurone to a motor neurone

Which of the following are antagonistic effects?

Below is a simplified diagram of an enzyme. What is shown by A?

The graph shows the rate of an enzyme controlled reaction. Point A represents the {{}} temperature for the enzyme.

The graph shows the rate of an enzyme controlled reaction. Why is the rate of reaction decreasing at point c?

If a significant increase in body temperature is sustained, it can lead to ...

Starter Quiz

Below is a simplified diagram of an enzyme. What is shown by A?