Circulatory system

• blood and
• bugs have hemolymph- mixture of blood and interstitial fluid

a system mainly found in invertebrates it mostly uses hemolymph. The heart pumps hemolymph to the vessels  that pump it into an open space where it's drained back into the heart.

The circulatory system transports gasses, nutrients and waste materials, it regulates body temperature and transports hormones. it also protects against blood loss and toxic substances introduced into the body

• Arteries- transport oxygen rich blood away from the heart
• veins- carry oxygen poor blood towards the heart
• capillaries- tiny vessels that separate arteries and veins. Where materials like gasses and nutrients are transferred to cells and where wastes like co2 are transported into the blood

arteries become smaller and turn into arterioles

veins become smaller and turn into venules

The artery expands as blood flows through it during the contraction of the ventricles. then snaps back during relaxation of the ventricles. causing the blood to move through the arteries. When the ventricles contract again this repeats.

capillaries

The walls tend to be very thick and highly elastic.

It has a small circumference which increases the pressure inside of the artery. This allows for faster expanding and snapping motions because of the force exerted by the blood on the walls of the artery, moving blood faster.

veins cannot contract to move blood to the heart so when the muscle around the veins contract the blood can move to the heart. It also contain one way valves that open when blood passes through and close when blood tries flowing backward to prevent blood from flowing backward

Thin and non elastic walls with a large inner circumference meaning less pressure

they contain an inner, middle and outer layer. but very in size 

• inner layer- contains endothelial cells that are very smooth to transport blood easily
• middle layer- smooth muscle and elastic fibers  (helps with elasticity when thicker)
• outer layer- made of copllagen

the outer layer are usually one cell layer thick( smallest blood vessel) for ez diffusion and the diameter is large enough for red blood cells to pass through single file. They are spread though a fine network throughout the body

blood flow is very slow in the capillaries to provide time for diffusion

controls the dilation and constriction of blood vessels to increase flow of blood to certain parts of the body.

• vasoconstriction.
• it decreases the blood flow near the skin to help conserve heat

vasodilation.

Increases blood flow near the skin to help reduce heat

pump blood throughout the body, ensure blood flow moves in one direction, separate oxygen rich blood from oxygen poor blood

• Four chambers.
• atrium- the top two they are filled with blood returning to the heart. 

ventricles- bottom two chambers that receive blood from atria and pump it away from the heart.

the thick muscular wall that separates the right side of the heart from the left

right-contains deoxygenated blood 

left- oxygenated blood

4 valves

the 2 atrioventricular valves (that control movement of blood from the atria and the ventricles

 2 semilunar valves that control movement of blood out of the heart

the tricuspid valve: separates the right atrium and the right ventricle.

bicuspid valve (mitral): separates the left atrium and left ventricle

tricuspid- TRI (contains 3 flaps)

bicuspid- BI (contains 2 flaps)

Pulmonary valve- separates the right ventricle from the pulmonary arteries

aortic valve- seperates the left ventricle from the aorta

vasoconstriction=cold

vasodilation=hot

where oxygenated poor blood travels to enter the right atrium

superior- deoxygenated blood from upper half of the body to get to the right atrium

inferior- deoxygenated blood from lower half of the body to get to the right atrium

where the right ventricle pumps blood through to get to the lungs for gas exchange (deoxygenated blood)

where oxygen rich blood enters into the left atrium

where the left ventricle pumps blood through to get it to all the body tissues (largest vessel)

transports oxygen-poor blood to the alveoli in lungs for oxygenation and CO2 removal using the capillaries . The pulmonary arteries transport the oxygen poor blood to the lungs from the right ventricle and at the alveoli the gas is exchanged through the capillaries and alveoli. The oxygen rich blood is transported from the capillaries to the hearts left atrium using the pulmonary veins

transports oxygen rich blood to deliver nutrients and remove wastes from cells throughout the body. The oxygen rich blood is supplied by the pulmonary pathway and makes its way into the aorta through the contraction of the left ventricle after it passes through the bicuspid valve. The aorta then transports the blood throughout the body

dedicated to provide blood to the muscle tissue of the heart itself. through the left and right coronary arteries

the heart itself provides the electrical signal

The sinoatrial node (pacemaker)

it stimulates the muscle cells to contract and relax rhythmically

the electrical signal spreads over the right and left atria making them contract simultaneously

firstly, an electrical signal is sent from the SA node (sinoatrial node) and it spreads over the left and right atria, causing them to contract simultaneously. As the atria contract, the signal reaches the atrioventricular node (AV). This node transmits the electrical signal through a group of specialized fibres called bundle of His (atrioventricular bundle) These fibres pass the signal through two bundle branches to the purkinje fibres. The purkinje fibres initiate the almost simultaneous contraction of the left and right ventricle

• sa node- right atria
• AV node- atrioventrical valve
• Bundle of his-septum
• bundle branches and purkinje fibres- ventricles

a machine used to measure change in voltage produced by the electrical signals from the SA node

occurs when valves don't close all the way (usually bicuspid) it can make heart less efficient causing faster beating or enlarging

The force exerted by blood against the vessel walls.

Systolic pressure- the maximum blood pressure during ventricular contraction. Blood is being forced into the pulmonary arteries and aorta increasing the pressure in those vessels.

diastolic pressure- the lowest pressure before the ventricles contract again. the ventricles relax and pressure in the pulmonary arteries and aorta drop.

• 120-systolic
• 80-diastolic

systole and diastole

systole- filled ventricles contract this pressure shuts the AV valves and opens the semilunar valves pushing blood to the arteries (either to pulmonary or body)

diastole- filled atria contracts. empty ventricles are relaxed and blood moves from the filled atria into the ventricles. AV valves open up and semilunar valves close

systole- ventricles contract (LUBB

diastole- Filled atria contract (DUBB

a blood pressure cuff used to measure blood pressure (measured at an artery in arm in mmhg)

high blood pressure which results from things like obesity inactive life style or stress it leads to things like heart attacks or strokes

a condition where arterial walls thicken and loose some of their elasticity, they become harder.

atherosclerosis is the most common its where plaque builds up on the inside of artery walls causing blood flow to decrease and blood pressure to increase. (caused by cholesterol and obesity)

chest pain because of plaque build up in certain areas. (it doesn't block the whole artery)

aspirin, clot busting medicines, and angioplasty

inserting a tube into clogged artery to remove plaque and placing a stent to increase artery diameter

a segment of healthy artery or vein is taken from somewhere else in the body and used to create a new pathway around a blockage

takes place usually in the heart at the coronary artery to remove blockage