A measure of how much change occurs per unit of time.

An exothermic chemical process that transfers energy for life processes, using glucose as fuel.

The substance that fits into an enzyme’s active site.

The part of an enzyme where the substrate binds.

Explaining the effect of different substrates on the rate of cellular respiration

Combined science

Pupils will learn 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.

Pupils learned about photosynthesis in producers, including a two-stage model of the process and the requirements and products of each stage.

Aerobic and anaerobic cellular respiration

the part of an enzyme’s structure where the substrate binds

a model used to explain why each enzyme can only catalyse one reaction

a substance that binds to the active site of an enzyme 

This apparatus is used to measure the volume of gas produced by cellular respiration. Air is trapped at the top when it is set up, before it is used. This will cause {{}} error in the results.

The volume of gas produced by respiration in 5 minutes was measured. The starting volume was 3 cm$$^3$$. The final volume was 28 cm$$^3$$. What is the rate of respiration in cm$$^3$$/min?

Each substrate is respired at a different rate.

Some substrates can be respired faster than others.

The respiration rates are similar for each substrate.

The rate of respiration is higher for glucose than the other substrates.

The rate of respiration is lowest for maltose.

Which statement **best** compares the rate of respiration for these substrates?

The rate for glucose is 5 times greater than for sucrose.

The rate for glucose is 4 times greater than for sucrose.

The rate for glucose is twice that for maltose.

The rate for maltose is less than twice that for glucose.

Maltose has to be split into two glucose molecules by an enzyme.

A new enzyme has to be made to respire maltose.

Maltose molecules have to be changed in shape.

Two maltose molecules have to be joined together to make glucose.

Maltose is made of two glucose molecules joined together. What has to happen to maltose before it can be used for cellular respiration?

This apparatus is used to measure the rate of cellular respiration of immobilised yeast. Which gas will be collected in the measuring cylinder?

Add water to the conical flask and swirl.

Place the bung and delivery tube into the top of the conical flask.

Place the conical flask in the water bath.

Wait 5 minutes for the conical flask/contents to get to water bath temperature.

This apparatus is used to measure the rate of cellular respiration of immobilised yeast with different substrates. Put the method into the correct order.

glucose + oxygen  --> water + carbon dioxide

Match the type of respiration to its correct equation.

they increase the substrate collision rate.

they are permanently changed by the reaction.

they provide a site for the reaction to take place.

Enzymes are catalysts. They speed up reactions because ...

Which statement is true **only** for aerobic cellular respiration?

The glucose used in all types of respiration is produced by plants or other organisms that have chlorophyll. What process produces the glucose?

Starter Quiz