Revision Questions Flashcards
Why can enzymes be described as biological catalysts?
This is because an enzyme can increase the speed of reaction without being changed or used up
Why do enzymes only usually catalyze one reaction?
This is because the enzyme’s active site has a unique shape to fit one substrate.
What does it mean when an enzyme has been ‘denatured’?
When an enzyme has been denatured it’s active site changes shape so that the specific substrate won’t fit anymore.
Describe how you could investigate the effect of ph on the rate of amylase activity
Put iodine in a spotting tile
Heat water using Bunsen burner (35 degrees)
Syringe amylase solution and starch and buffer solution into a boiling tube
Immediately mix the contents of the boiling tube and start the stop clock
Every 30 seconds drop a fresh sample using the pipette
If the solution remains browny-orange,starch is no longer present.
List three places where amylase is made in the human body
- Salivary Glands
- The Pancreas
- The Small Intestine
What is the role of Lipase?
To break down fatty acids and glycerol
Where is bile stored?
The Gall Bladder
Name the solution that you would use to test for the presence of lipids in food samples
Sudan III
Name the tubes that split off the trachea
Bronchus
Explain the role alveoli play in gaseous exchange
This is where gaseous exchange takes place. Between the alveoli and the capillaries
Explain why the circulatory system in humans is described as a double circulatory system
This is because the heart and the lungs work together to help us breath and get rid of waste product like carbon dioxide
Why does the heart have valves?
To prevent back-flow
Name the four chambers of the heart
Right atrium, right ventricle,left atrium,left ventricle
How is resting heart rate controlled in a healthy heart?
By a natural pacemaker, in the walls of the muscle in the heart
How are the arteries adapted to take blood away from the heart?
The walls are thick and elastic so they can take high pressure blood
They contain thick layers of muscle to make the stretch and spring back
Why do red blood cells not have a nucleus?
To make more room for the haemoglobin which carries oxygen.
Give two advantages and two disadvantages of statins
Advantages
1) Reduces the risk of stroke ,coronary heart disease and heart attacks.
2) Can increase the amount of good cholesterol
Disadvantages
1) Long term drug that has to be taken regularly
2) Can have negative side effects
What is the difference between biological and mechanical replacement heart valves?
Replacement biological valves are from other humans or other mammals but mechanical replacement valves are man made.
What is meant by non- communicable disease?
Can’t be spread between people or between animals . They last a long time and get worse slowly.
Give an example of where different types of disease might interact in the body
People who have problems with their immune system have more chance of getting communicable diseases like influenza
What is meant by a risk factor of a disease?
Risk factors are things that are linked to an increase in the likelihood a person will disease during their life
Which type of tumor is cancerous?
Malignant
what is a tissue?
A group of similar cells that work together to preform a particular functon
Explain what is meant by the term ‘organ system’
A group of organs working together to preform a particular function.
List the tissues that make up a leaf
Epidermal tissue
Palisade mesophyll tissue
Spongy mesophyll tissue
Meristem tissue
Explain how the structure of the upper epidermal tissue allows it to achieve its function
The upper epidermal tissue is made up of chloroplasts which need light. Furthermore their walls are thin to allow light to pass through.
What is the function of the phloem?
Transport things like water, minerals ions and food around the plant
What is transpiration?
The loss of water from the plant.
List the four main things that affect transpiration
Light intensity
Temperature
Air Flow
Humidity
Name the type of cell that help open and close the stormata
Guard Cells
