What are the 4 chambers of the heart?
Left and right atria and ventricles
Where does each circuit of a double circulatory system go?
Lungs and all the other organs of the body
Which blood vessel leaves the left ventricle?
Aorta
Which blood vessel leaves the right ventricle?
Pulmonary artery
What do heart valves do?
Prevent backflow
Why is the muscle on the left thicker than the right?
It has to pump the blood further
Why do arteries have thick muscular walls?
To withstand recoil (stretch and spring back)
What is useful about a capillary?
It is one cell thick - short diffusion pathway
Do veins have valves?
Yes, because the pressure is lower than arteries
Is blood a tissue or an organ?
Tissue
What shape are red blood cells?
Biconcave discs
Why don’t red blood cells have nuclei?
So they can pack in as much haemoglobin as possible
What is made when oxygen and haemoglobin combine?
Oxyhaemoglobin
What can white blood cells do? (3 marks)
Engulf and ingest pathogens Produce antibodies Produce antitoxins
What are platelets?
Small fragments of cells
What is plasma? Give 6 things it carries.
Pale straw coloured liquid which carries everything in the blood, including red and white blood cells, platelets, nutrients like amino acids and glucose, carbon dioxide, urea, hormones, antibodies and antotoxins
What is a stent?
A wire mesh tube which can widen arteries
What is artificial blood?
A substitute for blood
Which tissue in plants transports food?
Phloem
What vessel in plants transports water and ions?
Xylem
Are xylem vessels a continuous tube?
Yes, thickened with lignin
Which piece of apparatus measures transpiration rate?
A potometer
What is this?
An artificial heart