Circulatory system Flashcards
Circulatory systems purpose?
Transports blood to all body parts,
removal of waste from all body cells (metabolic waste which includes co2),
Transports hormones from endocrine glands to their target organs,
Transport of nutrients from digestive system to all body cells,
help protect body from viruses and blood cells
What function do the 4 chambers serve ( 2oxygenated, 2 deoxygenayed)
Structure: right side contains deoxygenated blood, left has oxygenated blood. Atria receive blood, ventricles pump blood.
Function: want to separate into 4 chambers so oxygenated and deoxygenated blood don’t mix
Atria have less muscle and receive blood, pass blood into ventricle which has a thicker wall of muscle to pump blood out of heart
Why does the heart need valves ?
Structure: flaps of muscle that come together and separate sections of heart
Function: Prevent blood from flowing in wrong direction (prevents backflow)
Allows for high pressure pumping action
What anatomical differences are there btw right and left ventricle?
Right: only pumps to lungs, less muscular
left: pumping blood to entire body, left needs more muscle to be able to pump the blood everywhere
What is the purpose of the septum?
Struc: Thick muscular wall that separates left and right of heart
Function: Prevents mixing or oxygenated and deoxygenated blood
Describe the flow of deoxygenated blood in the heart
From tissues its collected into the superior and inferior vena cava and fills right atrium.
Moves from right atrium into right ventricle through tricuspid valve
pumped from the right ventricle into pulmonary artery (thro pul valve), which leads to lungs (capillaries lie on top of alveoli for gas exchange)
Describe the flow of oxygenated blood in the heart
From the lungs moves to pulmonary vein and collects in the left atrium
Moves from left atrium into left ventricle through bicuspid valve
Then is pumped from left ventricle into the aorta thro aortic valve
Pumped from aorta to the tissues in our body
Pulmonarey circulation?
Flow of blood from heart to lungs for gas exchange
Systemic circulation?
Flow of blood from heart to body, supply organs/tissues with oxygen, nutrients, and remove wastes
What is the only organ that receives the full cardiac output?
The liver
What are the 3 parts of the electrical conduction and the heart?
SA node, AV node, His-Purkinje network
SA node:
Hearts natural pacemaker, electrical signal starts in SA node and spreads through walls of atria (both atriums), causing them to contract forcing blood into ventricles
AV node:
Delays signal, giving the atria time to contract before the ventricles do
His-Purkinje network:
Pathway of fibres that send an impulse to muscular walls of ventricles causing them to contract from apex (bottom) forcing blood up and out of heart
Whats the ECG
Measures the electrical impulses by a beating heart, doctors determine to find problems in heart. Straight line = dead
Blood pressure
Measure of pressure or force of blood against the walls of arteries while heart is contracting or relaxing. 2 measurements (systolic, diastolic)
Systole (contraction)
Pressure measurement of when ventricles contract.
blood moves out of the ventricle: blood from right ventricle gets pushed to the lungs and blood from left ventricle gets sent to body thro aorta
Diastole (relaxtion)
Measurement when ventricles are relaxed, blood moves into ventricle .
while ventricles are relaxed, blood from right/left atrium fills ventricles
What happens when a sphygmomanometer is inflated what happends?
prevents blood flow, no sound is heard
when pressure released, foirst sound is systolic, second diastolic
4 components of blood?
Plasma: liquid part of blood, dilute solution of salts, glucose, amino acids, urea etc
WBC: involved in immune system
Platelets: involved w blood clotting
RBC: involved w carrying 02
Red blood cells?
Erythrocytes, biconcave disc, no nucleus to have more space to bind 02 molecules
Func: transports 02 to tissues and c02 to lungs
How does structure relate to func (RBC)
Biconcave shape helps increase SA for gas exchange, Flexible so don’t get stuck in capillaries, diameter of RBCS is same diameter of capillary (increased gas exchange)
disease is sickle cell anemia
Hemoglobin
proteins found in RBC, composed of 4 protein chains, each containing heme group
1 RBC = 4 hemegroups = 4 molecules of 02
allows blood to carry 70x more 02 than if dissolved in plasma
Carbon monoxide
Poisonous due to high affinity to RBCS, carbon monoxide has easier time attaching to hemoglobin
Therefore replaces 02, deprives body of 02
White blood cells?
Leukocytes, various shapes depending on role in immune system, have a nucleus
Func: Immune defense, number in bloodstream can double when fighting infection
How does struc relate to func (WBC)
Some cells are larger and can engulf foreign particles/bacteria/viruses tagged for destruction
disease: leukemia
Platelets
Thrombocytes, platelike, no nucleus (fragments of cells produced by bone marrow) involved in clotting process
How does struc relate to func (platelets)
Chemicals in platelets allow them to stick (magenet) to cell wall of cut, forms clot overtime prevents blood from leaking out
hemophilia
Arties func and struc?
Func: carry blood away from heart
struc: small lumen diameter, thick muscle layer and highly elastic, no valves
How does struc relate to func (artery)
thick wall which is highly elastic allows to withstand the high pressure that heart exerts on the blood
Veins struc and func?
Larger diameter lumen than artery
func: Bring blood back to heart
struc: Less elastic connective tissue, has valves, prevents backflow and bring blood back to heart
how does struc help func (veins)
Blood lacks pressure, therefore walls don’t need to be as thick. The valves are required to help blood return to heart
Skeletal muscle pump
blood cannot travel back to heart by itself, skeletal muscles contract to push blood upwards.
muscles relax, blood falls until fills a valve, then closes and prevents backflow
Capillaries func and struc?
Func: site of internal gas exchange also allows for diffusion of nutrients and waste btw cells and bloodstream
structure: single cell thick, smallest vessel, diamnetrer only allows 1rbc to fit thro, no valves
Structure related to func (capillaries)
Single cell thick allows for exchange of gas and nutrients
Smaller diameter allows rbc to push against wall for easier gas exchange
