Terms - Circulatory system Flashcards
Heart
the heart powers the circulatory system
- allows blood to transport oxygen nutrients, waste, heat, hormones, and immune cells to the tissue
- pressure pumps through the body
What are the layers of the heart?
Fibrous pericardium (outter layer)
serous pericardium ( inner layer): Parietal Layer, visceral layer (space), and pericardial cavity
pericardium
is a fluid-filled sac that surrounds the heart in order to protect and lubricate it from proper function
How many chambers does a heart have? and how is it divided?
4 chambers
- Left and right sides are divided by the septum
Atria
the upper chamber of the wall (1 and 3 chambers)
ventricles
Lower chambers of the heart wall. (2 and 4 chambers)
What type of blood does the right atrium and ventricle?
deoxygenated blood
- most of the oxygen in the blood is removed from the muscle
What function do the Right atrium and ventricle have when they contain deoxygenated blood?
After the oxygen is removed from the muscle, it is located on the right side of the wall. It tries to get that blood to the lungs so it can be reoxygenated.
What type of blood does the left atrium and ventricle?
Oxygenated after it was reoxygenated from the lungs
Which chambers (Artia/Ventricle) are under low pressure when pumping/sending blood
The Artia is under low pressure because it is sent to the ventricles. (which isn’t far)
Which chambers (Artia/Ventricle) are under high pressure when pumping/sending blood
The ventricle is under high pressure because it is sending blood to the lung or systemic circulation
- as thicker walls
Heart valves function
The valves work to prevent backflow of blood
- open under pressure, then close to prevent backflow
Pulmonary Valve
between the right ventricle and pulmonary parties
tricuspid valve
- between the right atrium and right ventricle
mitral (bicuspid) valve
between the left atrium and left ventricle
Aortic valve
between the left ventricle and aorta
Aorta
Thick, muscular structure that distributes blood directly from the heart to the arteries of the body
How many heart chambers do fish have
They only have two heart chambers (one atria and one ventricle)
How many heart chambers do amphibians and reptiles have
They have three heart chambers (two atria and one ventricle)
How many heart chambers do birds and mammals have
They have 4 heart chambers (2 atria and 2 ventricles)
- crocodiles and alligators are the exceptions of having 4 heart chambers
How does the heart pump the blood through the body and to the tissue, then bring it back?
Arteries and veins connect the heart to the rest of the circulation system.
Arteries
Carry blood away from the heart.
- oxygen-rich (red color)
- under high pressure
- Thick walls
- elastic and muscular
Have three layers: Endothelial lining (inner), smooth muscle and elastic tissue (middle), and Connective tissue (outer)
veins
carry blood back to the heart
-deoxygenated and has been taken up by the tissue
- under lower pressure
- rely on skeletal muscle contraction to increase pressure (prevents backflow)
pulmonary circuit
the blood pathway from the right side of the heart to the lungs, and eventually to the left side of the heart
systemic circuit
the circulation pathway
through the body between left and right sides of the heart
What are the pulmonary circulation steps
- Blood is pumped from the right ventricle to the pulmonary arteries (contains blood with low concentration blood, used up by the tissue)
- Blood gets reoxygenated at the capillaries of the lungs (picks up O2 and expels CO2)
- Blood travels back to the heart via pulmonary veins to the left atrium (moving down the pressure gradient and contains blood with the highest O2 concentration)
Which part of the body contains the lowest part of oxygenated concentrated blood
the pulmonary arteries
Which part of the body contains the highest part of oxygen-concentrated blood
pulmonary veins
What are the systemic circulation steps?
- Left atria contracts and pushes blood to the left ventricle (contract due to an increase in pressure
- The left ventricle contracts and blood travels to the aorta (the mitral valve closes and prevents backflow. Blood travels through the aortic valve)
- In blood from the aorta travels to the entire body
- Blood reaches the capillaries ( at the capillary level O2 and nutrients are delivered. Co2 and water are picked up)
- Veins carry the blood back to the superior and inferior vena cava, which empty into the right atrium (reenters the heart)
- Blood from the right atrium goes to the right ventricle (through the tricuspid valve)
What does the tissue do when Oxygenated blood reaches the tissue?
- The tissue of the body ‘suck out’ the O2 from the blood. At the capillaries, the blood becomes deoxygenated
- The capillaries also deliver nutrients, and waste and CO2 are transported back
Systole
When the heart contracts to pump blood out
Diastole
When the heart relaxes after a contraction
- mnemonic: Di = double, so in the relax stage, it db the size
Pacemaker cells
cells of the heart in the sinoatrial (SA) node capable of generating their own electricity
- keeps the heart beating to the correct rhythm
- located in upper wall of the right atrium, the SA node is a group of specialized cardiac muscle cells that
initiate by contracting both atria and sending an impulse that stimulates the
AV node.
Electrical transmission
cells separated by intercalated disc
- contains gap junction
gap junction
allow ions to travel from one cell to another
Left atrium
after traveling though the lungs, oxygenated blood enters the left atrium via the pulmonary veins
Cardiac output equation?
cardiac output (CO) = Stroke volume (SV) x Heart rate (HR)
- CO: Volume of blood discharged from both ventricles each minute
- SV: volume of blood discharged from the ventricles with each contraction
- HR: number of heart contractions per minute
What is the conduction pathway within the heart?
- SA node (contracts both atria)
- Av node (signal delays slightly to allow atria to completely empty)
- Bundle of His: ( located between both ventricles
- Purkinje fiber: ( innervate the ventricle from bottom up. Both ventricles contract simultaneously)
What is the Stroke volume formula?
SV = End Diastolic volume (EDV) - End systolic volume (ESV)
- EDV: Volume of blood in the ventricle just before contraction
- ESV: Volume of blood in the ventricle at the end of contraction
blood pressure formula
blood pressure (BP) = Cardiac output (CO) x Systemic Vascular REsistane (SVR)
- BP: pressure of circulating blood against the vessels
- SVR: resistance to the flow of blood
blood vessels
Carry blood throughout the circulatory system
- Deliver oxygen and nutrients
- Transport waste products