Organisation in animals

Question 1

what are the 5 levels of organisation in living organisms

Answer 1

cells
v
tissues
v
organs
v
organ systems
v
organisms

Question 2

how does air move through the body

Answer 2

1) into the body through the nose or mouth
2) down the trachea
3) into the bronchi
4) the the bronchioles
5) into the alveoli (air sacs)
oxygen then diffuses into the blood in the network of capillaries over the surface of the alveoli

Question 3

what is an artery

Answer 3

they carry blood away from the heart artery at a high pressure. they have thick, muscular and elastic walls; the walls can stretch and withstand high pressure and contain small lumen.

Question 4

what is a vein

Answer 4

they carry blood to the heart at a low pressure. they have valves to stop the blood flowing the wrong way, containing thin walls and large lumen

Question 5

what is a capillary

Answer 5

they carry blood to tissues and cells and are connected to arteries and veins. they are one cell thick (short diffusion distance) and have very narrow lumen.