Cardiovascular Flashcards
Erythrocytes
-Red blood cells
-bi concave shape- no nucleus
-large surface area
-Transport oxygen to the body as the have haemoglobin
-Small and flexible to fit through capillaries
-Made in the bone marrow
Leucocytes
-White blood cells
-Types include lymphocytes, monocytes and neutrophils
Lymphocytes
-B cells- developed in the bone marrow and produce antibodies which attack from the outside
-T cells- developed in the thymus and attack cancer cells from the inside
Neutrophils
-Produced in the bone marrow
-Heal damaged cells
-Attracted to the chemicals produced by the damaged cells, arrive quickly
-Multi-lobed nucleus
Monocytes
-Produced in the bone marrow
-Big cells
-Circulate the body ready to fight infections
Platelets
-Produced in the bone marrow
-Helps to reduce infections
-Helps to clot the blood
Plasma
-Clear fluid
-Helps to regulate the body temperature
-Carries thing such as white blood cells, red blood cells, platelets, lipids, glucose and oxygen
Arteries
-Thick muscular walls
-Carry oxygenised blood away from the heart
-Small internal diameter
-Blood travels under high pressure
Capillaries
-Small and thin walls
-Exchange gas, water, oxygen, carbon dioxide and waste between blood and the tissues
Veins
-Thin walls
-Deoxygenated blood is carried to the heart
-Travels under low pressure
-Large internal diameter
2 circulatory systems
1.Pulmonary- the right side of the heart receives deoxygenated blood and pumps it to the lungs
2.Systemic- the left side of the heart receives oxygenated blood from the lungs and pumps it to the body
3 parts of the cardiac cycle
1.Atrial systole- contraction of the artias
2.Ventricular systole- contraction of the ventricles
3.Complete cardiac cycle- relaxation of the atrias and the ventricles
Blood flow
-Deoxygenated blood enters the right atrium via the vena cavas
-Blood is forced through the tricuspid valve into the right ventricle
-Blood is forced through the pulmonary artery where the deoxygenated blood is carried to the lungs
-Oxygenated blood from the lungs returns to the heart via the pulmonary vein and enters the left atrium
-Blood passes through the tricuspid valve into the left ventricle
-The blood is forced out of the aorta and the oxygenated blood is carried to the rest of the body
Sinoatrial node (SAN)
-Located in the upper wall of the right atrium
-Sets the rhythm of the heart
-Generates an electrical signal that causes the atria to contract
Atrioventricular node (AVN)
-Found in the bottom of the right atrium
-Delays the transmission of the electrical impulses from the SAN
-To allow time for the blood to go into the ventricles
Bundle of his
-Takes the impulse from the AVN to the septum where the purkijie fibres rapidly transmits impulses up to the ventricles cause them to contract
ECG traces
-P wave- contraction of the atria
-QRS complex- contraction of the ventricles
-T wave- relaxation of the ventricles
Heart attack and cardiac arrest
-Heart attack- one of the coronary arteries becomes blocked
-Cardiac arrest- heart stops pumping the blood around the body
Tissue fluid
-Capillaries are leaky so the fluid can leak through the gaps in the walls
-Blood arrives at the arterial end of the capillaries and is under pressure
-Hydrostatic pressure helps to force plasma out of the capillaries into the surrounding tissues where it is now called tissue fluid
-Tissue fluid delivers small molecules such as oxygen and glucose around the body
Reabsorption of tissue fluid
-Tissue fluid just return back to the circulatory system
-Most of the tissue fluid is pulled back into the venous end of the capillaries due to the osmotic pressure which is created by the high concentration of the proteins
-The fluid carries away carbon dioxide and waste products back into the blood stream
Lymph
-The remaining fluid drains into the lymphatic system which is a drainage and filtration system,
-Lymph vessels join the circulatory system at the top of the chest and return the fluid to the blood
Lymph nodes
-Swellings in the lymphatic system contain lymphocytes which filter out and destroy pathogens before returning the lymph into the blood
-Lymph nodes swell when fighting an infection
Blood pressure
-Is the force of blood against the arteries
-Systole- contraction of the heart muscles
-Diastole- relaxation of the heart muscles
Coronary heart disease
-Symptoms include- pain, shortness of breath and feeling sick
-Arteries become blocked from fatty deposits
-Treatments include- medication, surgery such as an artery bypass, lifestyle changes and ECG traces
