Cardiovascular System Flashcards
Cardiovascular system is a network composed of?
- Heart as the pump.
- Blood vessels that distribute blood throughout the body.
- Blood itself.
Main function of the circulatory system?
To deliver oxygen to body tissues whilst removing carbon dioxide.
Blood is?
- A liquid tissue.
- Cellular component suspended in a liquid called plasma.
- 5-6litres average male.
Plasma is?
55% blood.
90% water.
Consists of dissolved electrolytes like sodium, potassium and calcium.
Plasma proteins?
- Clotting factors (mainly prothrombin).
- Immunoglobulin.
- Polypeptides.
- Hormones.
Red blood cells etc come from?
A hematopoetic stem cell.
Lymphoid stem cells give rise to?
Types of lymphocytes.
Myeloid stem cells become?
Red, white blood cells.
Blood platelets?
- Role in blood clotting.
- Irregular shaped.
- Produced in bone marrow.
White blood cells?
- Attach foreign particles.
- Formed in bone marrow, spleen and lymphatic system.
- Colourless.
Classification based on lack or presence of granules.
Monocytes?
Can differentiate into macrophages.
3 types of lymphocytes?
B cells.
T cells.
Natural killer (NK).
B cells?
Develop into plasma cells.
Produce antibodies.
T cells?
Attack viruses, fungi and cancer cells.
Natural killed?
A wide variety of infectious microbes and tumour cells.
Red blood cells?
- Contain haemoglobin.
- Round and biconcave.
- Produced in bone marrow.
Haemoglobin has how many subunits?
4 subunits.
Haemostasis is?
Body’s natural response to an injury that’s stops bleeding and repairs the damage.
3 mecahnisms reduce blood loss from vessels?
- Vascular spasm.
- Platelet plug formation.
- Blood clotting-
Formation of prothrombinase, then prothrombin to thrombin and then fibrinogen to fibrin.
Blood clots?
Anticoagulants?
Prevent clotting.
Blood plasma contains?
Anti A bodies.
Anti B bodies.
Two special blood types?
Rh factor?
Is a red blood cell antigen.
Depends on presence or absence of Rh antigen.
Rh+ have
Rh antigen on it.
Rh-?
Do not have Rh antigen on it.
5 main types of blood vessels?
Arteries.
Arterioles.
Veins.
Venules.
Capillaries.
Arteries?
Carry blood away to body tissues from heart at high pressure.
Their walls consist of 3 layers:
Endothelium.
Smooth muscle (middle layer).
Outer layer.
2 major properties= elasticity and contractility.
Arterioles?
Are smaller arteries.
Deliver blood to capillaries.
Veins?
Return blood back to heart.
Transport blood under low pressure.
Valves ensure blood is flowing in right direction.
Venules?
Smaller veins.
Lack valves.
From capillary beds to veins.
Capillaries?
Small blood vessels that link arteries and veins together.
Are a site for gas and nutrient exchange.
3 layers of blood vessels?
(Tunica)
Intima.
Media.
Adventitia.
Vasoconstriction?
Decrease in diameter of lumen.
Vasodilation?
Is an increase in the diameter of the lumen.
Capillaries have very small thin walls that consist of a single layer of?
Endothelium.
Fenestrations?
Gaps in endothelium allows substances dissolved in blood plasma to move in and out.
Fluid movement between capillaries and tissues is controlled by 4 forces?
- Blood hydrostatic pressure.
- Blood colloid osmotic pressure (water potential).
- Interstitial hydrostatic pressure.
- Interstitial colloid osmotic (oncotic) pressure.
Net filtration occurs near?
Arterial end of capillary.
Since capillary pressure is greater than blood pressure.
Blood pressure?
Force that blood exerts on blood vessels.