9.1 Blood

consist of

plasma

red blood cells

white blood cells

platelets

straw coloured liquid

transport of carbon dioxide, digested food (nutrients), urea ?, mineral ions, hormones and heat energy

biconcave shape

no nucleus

protein : haemoglobin

side curve inwards

flexible so it squeeze through capillaries

large surface area : pick oxygen quickly

consist of nucleus

main type

phagocyte : engulf microorganism ( phagocytosis)

large cell

lymphocytes : release antibodies to destroy microorganism

to destroy pathogen

helping the blood to clot

platelet gather around the damage area to stop bleeding + protein (plasma) form tangle fine strands ---> trap the RBC and seal wound

capillaries close to cell

exchange material from rbc ---> cell OR cell ---> rbc (diffusion)

diffusion : movement of substance from high [] to low []

discuss oxygen & carbon dioxide

Blood test

sickle cell anaemia

  • genetic disease (mutation on DNA)
  • faulty Hb ( changes in Hb)

stiff & sickle shape (long thin C-shapes)

  • tend to get stuck in narrow blood vessels
  • cause tissue damage
  • blocking the flow of blood
  • strokes, blindness, or damage to the lungs, kidneys, or heart

malaria

  • caused by protozoa
  • lives in RBC & feed on Hb

reproduce & burst

  • infected RBC sticky together and block vessel

Sleeping sickness

cause by protozoa

spend life in blood

causes

fever

haedaches

joint pains

itching

invade brain

tired

confuses