What are the 4 main components of blood and give the percentage
- Plasma (55%)
-Platelets and white blood cells ( <1%)
-red blood cells (45%)
Give the function of the plasma and a description
FUNCTION: to transport substances around the body such as:
-waste CARBON DIOXIDE from cells to the lungs
-GLUCOSE from the small intestine to the cells
-WASTE PRODUCTS e.g. urea from the liver to the kidneys
- HORMONES to their target organs
-ANTIBODIES to fight disease
-WATER (plasma is 90% water )
NOTE: PLASMA IS A YELLOW LIQUID
Give the function of the platelets and a description
FUNCTION : to help blood clot when the skin is cut
-it is made from small fragments of other cells
-platelets ,along with fibrin threads, help form a blood clot which stops BLOOD LOSS and entry of GERMS
Give the function of the red blood cells and 4 adaptations
NVLB (said as envy ha-ha)
FUNCTION: to carry oxygen from the lungs to respiring cells
ADAPTATIONS:
-they have NO NUCLEUS so they can carry more haemoglobin
-they contain HAEMOGLOBIN which binds to oxygen
- they are VERY SMALL allowing transport through small capillaries
-they have a biconcave disc shape which gives them a LARGE SURFACE AREA :VOLUME RATIO for absorbing as much oxygen as possible from the lungs
Give the function of the white blood cells
they depend the body from pathogens (microorganisms that cause disease)
There are 2 different types of white blood cells:
Give the function of the PHAGOCYTES and a description /adaptations
FUNCTION: they engulf and digest pathogens
-they have a FLEXIBLE SHAPE AND MEMBRANE that allows them to engulf bacteria
-they have a LOBED NUCLEUS which allows them to engulf pathogens easily
-they digest pathogens using ENZYMES
Give the function of the LYMPHOCYTE and a description /adaptations
FUNCTIONS: they produce antibodies which bind to pathogens
-they have a LARGE NUCLEUS for making large amounts of antibodies (by protein synthesis)
-they PRODUCE ANTIBODIES which bind to pathogens and clumps them together ,making it easier for phagocytes to engulf
How does haemoglobin work?
-give the equation
Haemoglobin + oxygen → oxyhaemoglobin
Explain how haemoglobin works
(meorise , this is important)
- The haemoglobin molecules in red blood cells BIND with oxygen in the alveoli of the lungs to form oxyhaemoglobin
-The blood is pumped to the rest of the body , when it enters an area of LOWER oxygen concentration , the REVERSE OCCURS and the haemoglobin is now DEOXYGENATED
(oxyhaemoglobin splits up)
-the oxygen DIFFUSES into cells for respiration
What is the name of the vessels that carries blood from the:
a) heart to the body
b) body to the heart
c) heart to the lungs
d) lungs to the heart
-out of these 4 , only one is an artery . Which is it?
a) AORTA
b) VENA CAVA
c) PULMONARY VEIN
d) PULMONARY VEIN
AORTA IS AN ARTERY
Explain where the following go to:
Pulmonary circuit
Systemic circuit
Pulmonary circuit:
heart → lungs → heart
Systemic circuit:
heart → body → heart
What are the 3 types of vessels?
- arteries
-veins
-capillaries
Give 3 ADVANTAGES of the dual circulatory system
(compared to a single circulatory system which is like heart → lungs → body → heart)
- higher PRESSURE can be maintained
(blood returns to the heart after lungs and gets pumped again)
2.greater FLOW OF BLOOD to the tissues
(higher pressure → moves faster)
- tissues can be more ACTIVE
(more oxygen → more respiration)
Give 5 features of the :
ARTERIES
ARTERIES…
-carry blood under HIGH PRESSURE
-have THICK muscular and elastic walls
-carry blood AWAY from the heart
-carry OXYGENATED blood (except the pulmonary artery)
-they have a NARROW lumen
Give 6 features of the :
VEINS
VEINS….
- carry blood under LOW PRESSURE
- have THIN walls
- have WALVES to prevent backflow of blood
- carry blood BACK TO the heart
-carry DEOXYGENATED blood ( except pulmonary vein)
-have a LARGE lumen
note: thin walls as they carry blood under low pressure
Give 5 features of the :
CAPILLARIES
CAPILLARIES ….
-carry blood under LOW PRESSURE
(this allows the exchange of substances)
-connect ARTERIES to VEINS
- wall are ONE CELL THICK and PERMEABLE
(a substance can pass through) - exchange materials with TISSUES
-carry BOTHE oxygenated and deoxygenated blood
