B - Cardiovascular System Flashcards
What is the heart made from?
Cardiac Muscle (myocardium)
What is the function of the left atrium?
Collects oxygenated blood from lungs
What is the function of the right atrium?
Collects deoxygenated blood from body
What is the function of the left ventricle?
Pumps oxygenated blood to body through aorta
What is the function of the right ventricle?
Pumps deoxygenated blood to lungs through pulmonary artery
What is the function of the bicuspid valve?
Prevents backflow between LA + LV
What is the function of the tricuspid valve?
Prevents backflow between RA + RV
What is the function of the aortic valve?
Sits between the aorta and LV, prevents backflow from aorta
What is the function of the pulmonary valve?
Sits between pulmonary artery and RV, prevents backflow from vena cava
What is the function of the chordae tendineae?
Stops valves from turning inside out
What is the function of the septum?
Dividing wall that seperates the two sides of the heart
What is the function of the coronary arteries?
Transports oxygenated blood to myocardium directly
What is the function of the aorta?
Transports blood away from heart to body
What is the function of the vena cava?
Transports deoxygenated blood from body to RA
What is the function of the pulmonary artery?
Transports deoxygenated blood from RV to lungs
What is the function of the pulmonary vein?
Transports oxygenated blood from lungs to LA
Which circulation is deoxygenated?
Pulmonary
Which circulation is oxygenated?
Systemic
Order the route that a drop of blood would take through the heart
1) Vena cava
2) Right atrium
3) Tricuspid valve
4) Right ventricle
5) Pulmonary valve
6) Pulmonary artery
7) Lungs
8) Pulmonary vein
9) Left atrium
10) Bicuspid/mitral valve
11) Left ventricle
12) Aortic valve
13) Aorta
14) Coronary arteries
What are the 2 semi-lunar valves?
Pulmonary and Aortic Valve
What are the 2 atrioventricular valves?
Bicuspid/mitral and tricuspid valve
What are the 5 different types of blood vessels?
Arteries
Arterioles
Capillaries
Venules
Veins
What is the function of the epithelium?
Smooth inner lining to allow for lamina flow of blood
What is the function of smooth muscle?
Allows for expansion or relaxation and contraction to enable peristalis (muscle contraction)
What is the function of connective tissue?
Protective cartilage that can expand/contract with the smooth muscle, withstanding pressure changes
What is the function of a valve?
They assist with the return of blood to the heart against gravity in the right direction, and prevents blood pooling
What is the function of basement membrane?
Provides support and structure; creates barrier between capillaries/organs, but allows diffusion
List 6 features of arteries
1) Thick muscular walls with a small lumen
2) Contains elastic cartilage and smooth muscle
3) Withstands high pressure
4) Carries oxygenated blood
5) Contains smaller branches called arterioles
List 5 features of capillaries
1) One cell thick walls
2) Very low pressure
3) Slow blood flow
4) Most prolific blood vessel in body
5) They form networks around muscles and organs
List 6 features of veins
1) Oval shaped with thin walls, wide lumen
2) Less muscular than arteries
3) Low pressure
4) Have valves
5) Carry blood back to heart
6) Carry deoxygenated blood
What are the 4 components of blood?
Red Blood Cells
White Blood Cells
Platelets
Plasma
What’s the fancy name for red blood cells?
Erythrocytes
What’s the fancy name for white blood cells?
Leucocytes
What’s the fancy name for platelets?
Thrombocytes
Approximately how many litres of blood does an adult have in their body?
5 litres
Aside from oxygen, name 3 other substances transported by blood
Carbon Dioxide
Nutrients
Water
What does the lymphatic system consist of?
Lymphatic vessels, lymph and lymph nodes
Lymph nodes are distributed all around the body. Name 6 places
1) Jaw
2) Neck
3) Elbow
4) Armpit
5) Knee
6) Groin
Why do lymphatic vessels have valves?
To ensure lymph flows in one direction only
What is lymph?
A pale-yellow fluid, containing lymphocytes
What are the four functions of the cardiovascular system?
Transportation
Thermoregulation
Fighting infection
Clotting
Which side of the heart pumps oxygenated blood?
Left
What side of the heart does deoxygenated blood enter?
Right
The right ventricle pumps blood through the pulmonary artery to the lungs. Here the blood picks up oxygen and carbon dioxide is released into the lungs. From the lungs the oxygenated blood is transported to the left atrium.
What is this loop called?
Pulmonary circulation
From the left atrium, blood flows down into the left ventricle, the left ventricle pumps oxygenated blood through the aorta to all the systems and tissues of the body. Oxygen and nutrients are released from the blood to nourish cells, and carbon dioxide and other waste products are carried back to the heart via the two vena cava.
What is this loop called?
Systemic circulation
At rest, approximately what % of blood travels to the skeletal muscles?
15%
During maximal intensity exercise, what % of blood travels to skeletal muscles?
85%
During exercise, blood is directed to the blood vessels close to the surface of the skin.
Why?
To help with thermoregulation
What is the narrowing of blood vessels called?
Vasoconstriction
What is the widening of blood vessels called?
Vasodilation
The cardiovascular system fights infection in 2 ways. What are they?
White blood cells - destroy bacterial infections
The lymphatic system - clears away infections
Blood clots by changing from a _______ to a ___ which then forms a ____.
Once the body detects that a _____ ______ has been damaged, _________ are directed to the site and ‘______’ together.
They release __________ which act on proteins called _____________ that are already circulating in the blood.
The __________ proteins join together to create ______ ______, creating a ____ across the injury site which acts like a plaster to seal it.
Blood clots by changing from a liquid to a gel which then forms a scab. Once the body detects that a blood vessel has been damaged, platelets are directed to the site and ‘clump’ together. They release chemicals which act on proteins called fibrinogens that are already circulating in the blood. The fibrinogen proteins join together to create fibrin fibres, creating a mesh across the injury site which acts like a plaster to seal it.
What is the contraction of the heart called?
Systole
What is the relaxation of the heart called?
Diastole
What is the name of the hearts’ independent nerve supply?
Sino-atrial node
Where is the sino-atrial node loacted?
In the right atrium, situated close to the point where the vena cava enters
State 4 facts about erythrocytes (RBC’s)
-Make up 99% of all blood cells
-Red in colour due to haemoglobin
-Main role is transportation of oxygen
-5 million RBC’s per 1ml of blood
State 4 facts about leucocytes (WBC’s)
-Colourless/transparent
-Far fewer WBC’s than RBC’s, 1:700
-Fight infection as part of the immune system
-Destroy bacteria and remove disease
State 3 facts about platelets
-They are parts of cells
-Prevent blood loss via clotting
-Clump together when exposed to air, requires factor 8
State 3 facts about plasma
-Liquid part of blood
-Straw coloured
-Contains the solid constituents of blood (haematocrit)
What does myogenic mean?
Generates its own nervous impulse
List the pathway of a nervous impulse through the heart
1) The impulse is generated in the SA node, located in the right atrium
2) The impulse travels across both atria, making them contract
3) Onto the atrio-ventricular node, located in the septum where the atria and ventricles meet
4) Slight pause, and then the impulse enters the ventricle walls through the bundle of His
5) The impulse finally travels to the purkinje fibres, which spread the impulse across all parts of the ventricles and they contract
The heart is controlled by the _________ nervous system
Autonomic
What are the 3 phases to the cardiac cycle?
-Atrial and ventricular diastole
-Atrial systole
-Ventricular systole
What is the atrial and ventricular diastole?
The heart relaxes and fills
What is the atrial systole?
The atria contract and the remaining blood is pushed into the ventricles
What is the ventricular systole?
The ventricles contract and push blood out through the aorta and pulmonary artery
The ______ nerve ______ down the heart rate and __________ the power of ___________ contraction by delivering impulses through the ____-______ node
The vagus nerve slows down the heart rate and decreases the power of ventricular contraction by delivering impulses through the sino-atrial node
What do the sympathetic nerves do?
Increases the heart rate and force of ventricular contraction
Where is the autonomic nervous system controlled?
Through the cardiac centre in the brain, positioned within the medulla oblongata
