1. Dawn Genner

2. Red cells:
 Most common blood cell, making around 45% of the
blood.
 Doughnut-shaped.
 Do not have a nucleus.
 Contain haemoglobin (which is why they’re red)
 Live for approximately 120 days.
 Carry oxygenated blood from lungs to cells that
need it.

3. White cells
 Search for bacteria
 Carry antibodies
 Antibodies = our bodies’ defences against viruses
and bacteria.
 Part of: our immune system.

4. Platelets
 Fragments of cells
 Used to help clot (coagulate) the blood.
 Platelets live for an average of 10 days.

5. Plasma
 Is a pale yellow colour
 Is 90% water
 Plasma allows other blood cells to move around.

6.  It is made in the centre of our bones = in our bone
marrow.

7. There are three types of blood vessel:
Arteries
 Carry blood away from the heart
(always oxygenated apart from the pulmonary
artery which goes to the lungs)
 Have thick muscular walls
 Have small passageways for blood
(internal lumen)
 Contain blood under high pressure

9. Veins
 Carry blood to the heart (always de-oxygenated
apart from the pulmonary vein which goes from
the lungs to the heart)
 Have thin walls
 Have larger internal lumen
 Contain blood under low pressure
 Have valves to prevent blood flowing backwards

11. Capillaries
 Found in the muscles and lungs
 Microscopic – one cell thick
 Very low blood pressure
 Where gas exchange takes place. Oxygen passes
through the capillary wall and into the tissues,
carbon dioxide passes from the tissues into the
blood

12.  When an infective cell is detected, white blood
cells will send out a message to another type of
cell: t-helper cells.
 This also triggers your immune system.Your body
releases millions of antibodies to fight off the
enemy cells.
 The antibody cells join themselves to the bacterial
cell in an attempt to overpower it.

13.  As this process continues, the number of infectious
cells will decrease and the body can stop the battle.
 Another kind ofT cell, theT-suppressor cell (orT8 cell),
will send out messages to the other cells and "de-
activate" them.
 Without theT-suppressor cells, the body would
continue trying to fight off a disease that no longer
exists (and eventually would end up fighting its own
cells).

14.  Bruising is caused by blood vessels becoming
damaged, which causes bleeding into the skin.

16.  Control of body temperature
 Keeping out infection
 It´s a waterproof barrier
 Protects delicate tissues underneath
 Mends itself when damaged

17.  Plants: structure and cells
 What can you remember?!?!?!