Organisation in animals

Question 1

Function of platelets

Answer 1

form blood clots - prevent loss of blood and wounds becoming infected

Question 2

structure of air passes when breathing in

Answer 2

mouth/nose -> trachea -> bronchi -> bronchioles
-> alveoli

Question 3

structure of capillary and function

Answer 3

carries blood to cells and tissues
-one-cell thick wall to provide short diffusion distance

Question 4

structure of vein and function

Answer 4

carries blood back to heart at low pressure - has valves to prevent backflow of blood

Question 5

structure of artery and function

Answer 5

carries blood away from the heart under high pressure - small lumen and thick, elastic walls that stretch

Question 6

why is circulatory system a double circulatory system

Answer 6

blood passes through the heart twice for every circuit around the body - deoxygenated blood pumped from right heart to lungs, oxygenated blood returns from lungs pumped from left heart to body

Question 7

substances transported in blood plasma

Answer 7

hormones, proteins, urea, carbon dioxide, glucose

Question 8

2 methods of protection for white blood cells

Answer 8

-engulf pathogens (phagocytosis)
-produce antitoxins to neutralise toxins

Question 9

4 main components of blood

Answer 9

red blood cells, white blood cells, plasma, platelets

Question 10

function of saliva

Answer 10

lubrication to help swallowing - contains amylase

Question 11

function of bile in digestion (stored in gall bladder, produced by liver)

Answer 11

-neutralises hydrochloric acid from stomach
-emulsifies fat to small droplets with a large surface area

Question 12

name 5 levels of organisation in living organisms

Answer 12

cells -> tissues -> organs -> organ systems -> organism