Blood cells

1. Compare the structure of white and red blood cells. [3 marks]

WBC RBCmade in bone

marrow from stem cells

source made in bone marrow from stem cells

irregular with lots of extensions

shape ALL are biconcave disc (no variation)

has nucleus (and is long)

nucleus

RBC has no nucleus (loses nucleus before it enters

blood)WBC has no Hb molecules inside

hemoglobin

RBC has many Hb molecules inside

2. Compare the function of white and red blood cells. [3 marks]

leukocyte (trait) erythrocytetravels in blood movement travels in blood

immune response

purpose transport oxygen

leukocyte moves in blood vessels

and between cells and in

lymph system

location of movement

erythrocyte move in blood only

leukocyte phagocytozes (eats) bacteria

phagocytosis

erythrocyte does not do any

phagocytosis

3. Describe one structure to function relationship in white blood cells. [3 marks]

namedescribe structure

indicate function

The nucleus of the leukocyte...

is long and narrow...

to let the leukocyte slip between cells, in narrow gaps.

The leukocyte has a cell membrane...

which is flexible and can be extended and folded...

so that the leukocyte can “engulf” bacteria (and then digest them)

Leukocytes contain “granules”...

which are vesicles filled with enzymes and chemicals...

that digest or breakdown bacteria

4. Describe one structure to function relationship in red blood cells. [3 marks]

namedescribe structure

indicate function

The erythrocyte’s shape...

is biconcave disc...

which provides maximum diffusion rate into cell with maximum volume

Erythrocyte’s shape ...

is circular and smooth ...

so it glides through small openings without getting stuck or jammed.

Erythrocytes contain hemoglobin

which is a protein that has iron atoms in it ...

and this protein/Fe complex binds oxygen to carry oxygen from lungs to cells.