B4 - Organising animals and plants Flashcards
- What are the components of blood? (4 marks)
- Red blood cells
- White blood cells
- Platelets
- Plasma
- Give one function of red blood cells (1 mark)
Carry oxygen from the lungs to the cells of the body
- What is the red pigment in red blood cells called? (1 mark)
*
- What is the function of haemoglobin? (3 marks)
- To combine with oxygen to make oxyhaemoglobin
- To carry oxygen to the cells
- To release oxygen at the cells
- Give one function of white blood cells (1 mark)
Defence against pathogens
What are platelets? (1 mark)
They are small fragments of cells
- Give one function of platelets (1 mark)
Clot at the site of a wound
- Give one function of plasma (1 mark)
To carry dissolved substances, such as glucose, around the body
- What is the function of the circulatory system? (1 mark)
- To transport substances around the body
- What are the four chambers of the heart called? (2 marks)
- Left and right atria
- Left and right ventricles
- Label the structures in the heart (4 marks)
- How does the heart push blood around the circulatory system? (1 mark)
Heart muscle contracts
- How is backflow prevented in the heart and veins? (1 mark)
Valves
What are the differences between arteries and veins? (4 marks)
- Arteries have:
- Thick wall (to contain blood at high pressure)
- Elastin in the walls
- Veins have:
- Thin walls
- Valves to stop backflow
- What is the function of a capillary?
They bring nutrients and oxygen to tissues and remove waste products.
. Name the types of blood vessels shown (3 marks)
- How do you calculate the rate of blood flow?
heart rate x stroke volume =cadiac output
- Give the ways in which the composition of the blood in the pulmonary vein is different to that in the pulmonary artery (3 mark)
- Pulmonary artery has less O2
- Pulmonary artery has more CO2
- Pulmonary artery has more glucose
- Name this blood vessel (1 mark)
Coronary artery
- Give methods of treating a blocked coronary artery (above) (4 marks)
- Stent
- By-pass with a new blood vessel
- Statins
- Balloon
. How does a stent work? (2 marks)
- It keeps the artery open
- To allow blood through
. How does a by-pass work? (2 marks)
It connects a new blood vessel around the blockage to allow blood through
. How do statins work? (2 marks)
- Lower cholesterol
- Remove blockage
How does an arterial balloon work? (2 marks)
It widens the blood vessel to allow blood through
Suggest factors that scientists must consider so that heart valves can work effectively in the heart
- That it is the correct size
- That it doesn’t cause an immune response and get rejected
- Whether it is a long lasting material
- If it’s strong enough to withstand pressure
- That it will open at the right pressure
- That it doesn’t cause clotting
- That it doesn’t leak
- That it is non toxic
What is a pacemaker? (1 mark)
A pacemaker is a small device that’s placed in the chest or abdomen to help control abnormal heart rhythms
What are the features of an exchange surface that allow efficient exchange (4 marks)
- Large surface area
- Thin to provide a short diffusion pathway
- Efficient blood supply (in animals only)
- Well ventilated (in animals for gas exchange)
- Where does gas exchange take place in the lungs? (1 mark)
Alveoli
- What structure increases the surface area of the lungs? (1 mark)
- Alveoli
What structure increases the surface area of the small intestine? (1 mark)
Villi
- Why do villi have an extensive network of capillaries? (2 marks)
- To provide a good blood supply
- For transporting nutrients
- Where are the lungs? (1 mark)
Upper thorax
- What structure protects the lungs? (1 mark)
Ribs
- Which process takes air into the lungs? (1 mark)
Breathing
- Which gases are exchanged at the surface of the alveoli? (2 marks)
- O2
- CO2
- Name one substance other than food that an organism must exchange with its environment (2 marks)
- O2
- CO2
- Describe the changes in volume of the lungs in one breathing cycle (2 marks)
- Rises then falls
- Give data from a graph or table to back up your point!
- Explain how the diaphragm and ribcage cause changes in lung volume (6 marks)
- Rise in volume caused by
- Upward and outward movement of lungs
- Flattening of diaphragm
- Decrease in volume caused by
- Downward and inward movement of the lungs
- Doming of diaphragm
What is the process of taking air into the lungs and expelling it known as? (1 mark)
Ventilation
- How does an iron lung support breathing? (8 marks)
- The person lies inside
- Air is pumped out
- Pressure decreases around the patient
- Thorax and lungs expand
- Air pumped back in
- Pressure increases
- Thorax moves inwards
- Lungs deflate
- Give advantages of using a modern ventilator over using an iron lung (3 marks)
- More able to move
- More portable
- Doesn’t affect pressure and therefore blood flow in the body
- Give disadvantages of using a modern ventilator over using an iron lung (2 marks)
- Tube may be uncomfortable
- More difficult to eat/talk
- How is a plant root adapted for absorbing water? (5 marks)
- There are many hairs that are one cell thick
- Which gives a large surface area
- With a short diffusion pathway
- So there is more diffusion or osmosis
- Into the root
- Explain why roots have to use two methods for absorbing water and ions in their roots (4 marks)
- Solution is dilute in soil
- Water moves from the dilute solution into the more concentrated cell (osmosis)
- Concentration of ions in soil is less than in the cell
- Ions move against the concentration gradient (active transport)
- Give the function of the stomata (3 marks)
- To allow CO2 to enter
- To allow O2 to leave
- To control evaporation of water (transpiration)
- Name the cells that control the size of the stomata (1 mark)
Guard cells
Give a disadvantage of having a large number of stomata per mm2 on a leaf (1 mark)
More water loss
- Explain why very little water loss occurs when the underside of a leaf is covered in grease (3 marks)
- The lower surface has most stomata
- Stomata are covered by grease
- Water cannot escape
- How is water transported in a plant? (1 mark)
In the xylem
- How are dissolved sugars transported in plants? (1 mark)
In the phloem
- What is transpiration (4 marks)
- Movement of water from roots
- Via the xylem
- To the leaves
- Water evaporates through stomata
- What is the role of stomata and guard cells?
To control gas exchange and water loss.
- Which factors affect transpiration
- temperature
- humidity
- light intensity
- amount of air flow
- What is a potometer? (1 mark)
A is a device used for measuring the rate of water uptake of a leafy plant shoot.
What is diffusion? (2 marks)
- Movement of substances
- From an area of high concentration to an area of low concentration
What is osmosis? (4 marks)
- Movement of water
- Through a partially permeable membrane
- From a dilute to a concentrated solution
- It’s passive
What is active transport? (3 marks)
- Movement of substances
- Against the concentration gradient (from an area of low concentration to a high concentration)
- Requires energy
