Transport In Humans

Question 1

components of blood

Answer 1

1. red blood cell
2. white blood cell
3. platelets
4. plasma

Question 2

function + structure (rbc)

Answer 2

function : transport oxygen from lungs to the other parts of the body
structure :
- biconcave, circular in shape
- no nucleus
- contains haemoglobin
- flexible
adaptations :
- contains haemoglobin - binds to oxygen
- biconcave shape - increase surface area-to-volume ratio/rate of absorption/release of oxygen
- no nucleus - more space for haemoglobin

Question 3

function + structure (wbc)

Answer 3

functions :
- phagocytes : perform phagocytosis (wbc engulfs and destroys foreign particles)
- lymphocytes :
- irregular in shape
- each have a nucleus
- produce antibodies
antibodies :
- destroy disease-causing particles
- cause bacteria to clump up together for easy ingestion by phagocytes
- neutralise toxins produced by bacteria

Question 4

function + structure (platelets)

Answer 4

• function : blood clotting
  1. injury –> open wound
  2. soluble fibrinogen –(platelets : enzyme)–> insoluble fibrin threads
  3. insoluble fibrin threads and platelets will create blood clot to protect the body from :
  
  • exposure to foreign particles
  • loss of blood
    4. forms a scab

Question 5

function + structure (plasma)

Answer 5

• contains mainly water and substances (eg. glucose, salts, amino acids, fats, vitamins, hormones and metabolic waste such as urea) + rbc and wbc
  transports :
• blood cells around the body
• nutrients from small intestines to other parts of the body
• metabolic waste products from organs (kidneys, lungs)
• hormones from endocrine glands to target organs

Question 6

types of blood vessels

Answer 6

1. artery
2. capillary
3. vein

Question 7

function + structure (artery)

Answer 7

direction of blood flow : away from the heart
blood pressure + speed of blood flow : high pressure/fast-moving
type of blood transported : oxygenated (except for pulmonary artery : deoxygenated)
adaptation : thick, muscular, and elastic
- thick, muscular : withstand the high blood pressure
elastic : stretch and recoil/spring back (push blood in spurts + gives rise to pulse)

Question 8

function + structure (vein)

Answer 8

• direction in blood : towards the heart
• blood pressure + speed of blood flow : much lower than artery/more slower and smoother
• type of blood transported : deoxygenated (except pulmonary vein : oxygenated)
• adaptation : valves - prevent backflow of blood

Question 9

function + structure (capillary)

Answer 9

• function : exchange of substances
• one cell thick walls : increases rate of diffusion -

Question 10

cardiac cycle

either draw out or verbalise

Answer 10

deoxygenated blood from all parts of the body -> veins –> vena cava –> right atrium -(tricuspid valve)-> right ventricle -(pulmonary artery)-> LUNGS (oxygen) -(pulmonary vein)-> left atrium -(bicuspid valve)-> left ventricle –> aorta –> rest of the body –> back to the start

Question 11

atrial contraction

Answer 11

• blood from the atria is forced into the ventricles on either side

Question 12

ventricular contraction

Answer 12

• blood is forced out of the heart
• right side : transported to the lungs through the pulmonary artery
• left side : transported to the rest of the body through aorta

Question 13

kidney, heart, lungs, liver

name of artery/vein

eg. ____ vein / ____ artery

Answer 13

• kidney : renal
• heart : coronary
• lungs : pulmonary
• liver : hepatic + hepatic portal vein