B3 - Exam Mistakes Flashcards
Explain how stents work. 2 marks
Stents hold open blood vessel
Allowing more blood to flow through
Give the type of blood vessel that gets blocked up
Artery
Give one way that the blood is different in a vein than in an artery
Vein contains LESS oxygen than artery
Explain how the diaphragm and ribcage cause the changes in lung volume shown in the diagram. 4 marks
Air comes in due to flattening of diaphragm
Air goes out due to expansion of diaphragm
Air comes in due to outward movement of rib cage
Air goes out due to inward movement of rib cage
Describe the difference between the iron lung and the artificial ventilator. 2 marks
In iron lung, the atmospheric pressure forces the air in and out of the lungs
In the artificial ventilator, air is forced mechanically into lungs
Give one advantage and disadvantage of using modern ventilator instead of iron lung
Freedom of movement
But tube is uncomfortable
Give 4 reasons for a longer food chain giving less food
Energy loss by movement of animals
Energy loss by body temperature of animals
Lost in waste materials
Lost in inedible parts of animals
DON’T SAY RESPIRATION
What is meant by the transpiration stream? 3 marks
Water moves from roots up the stem to the leaves
Water evaporates
Via stomata
Give one substance apart from food needed by animals to grow
Oxygen
Why would the concentration of glucose in the blood coming from the small intestine be lower 6 hours after a meal?
Most of glucose has already been absorbed
Why would amount of fish caught every year decrease and then increase. 2 marks
Decrease due to over fishing
Increase due to quotas and net size working
Why would fish caught from sustainable sources increase?
Public awareness of over fishing
Give 2 reasons for fish growing in cages to grow faster
More food available (given by humans)
Less energy loss through movement
Give 4 factors that a scientists needs to consider when designing an artificial heart valve
Valve size to fit
Long lasting material
Doesn’t cause immune response
Blood doesn’t clot
Describe how the body responds to a decrease in blood glucose concentration. 3 marks
Pancreas detects low blood glucose
Glucagon secreted by pancreas
Travels to kidneys and causes glycogen to turn back to glucose
Why does core body temperature decrease due to exercise. 2 marks
More exercise done so more respiration needed to provide energy
Respiration causes more waste energy as heat
Why would biogas produced in the first few days not burn? 3 marks
There is initially oxygen
Aerobic respiration by microorganisms
Producing carbon dioxide only which doesn’t burn
Why do potato peelings release more biogas than pasta?
More carbohydrates
Give 2 reasons for the mass of household waste increasing every year
Growth in population
Improved living standards
