Page 143 - Knowledge Organiser Yr9 24-25

Knowledge Base: Science B2: Organisation in animals Year 9
5. Rate of Enzyme Action
5.1
Name two factors which affect the rate of enzyme action.
Temperature, pH.
5.2
What product does amylase break starch down into?
Glucose.
Practical: Does pH effect the rate at which starch is broken down by the enzyme amylase?
5.6
Why must a water bath be used
during the practical?
To control the temperature.
5.7
What is the independent variable in this investigation?
The pH.
5.8
What is the dependent variable in this investigation?
The time taken for starch to fully breakdown.
5.9
What are the control variables in this investigation?
• Volume of amylase solution
• Volume of starch solution
• Concentration of amylase solution • Concentration of starch solution
• Temperature
5.10
What is the purpose of iodine in this investigation?
To test for the presence of starch to determine if it has been broken down.
5.11
Why is continuous sampling used in this investigation?
To test for the presence of starch in a sample at regular intervals.
6. The Lungs
6.1
What structure protects the lungs?
Rib cage.
6.2
What are the structures called where gas exchange happens?
Alveoli.
6.3
Name substances that are exchanged in gas exchange at the alveoli.
Oxygen moves into the blood stream and carbon dioxide moves into the alveoli.
6.4
How do substances move between the alveoli and bloodstream?
By diffusion.
6.6
State the pathway of air from the atmosphere to the blood.
Nose/ mouth → trachea → bronchi → bronchioles → alveoli → blood.
6.7
How are lungs adapted for gas exchange?
• Breathing moves air in and out.
• Many alveoli.
• Large capillary network around the alveoli. • Alveoli and capillaries are one cell thick.
6.8
How does moving air in and out of the lungs aid the diffusion of gases?
Maintains the concentration gradient.
6.9
How does having many alveoli aid the diffusion of gases?
Provides a large surface area.
6.10
How does a large capillary network around the alveoli aid the diffusion of gases?
Maintains the concentration gradient.
6.11
How does the alveoli and the capillaries being one cell thick aid the diffusion of gases?
Provides a short diffusion path.
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