Heart and blood vessels

A network of organs and vessels that transport nutrients, oxygen, and blood - Made up of heart and blood vessels - Two distinct LOOPS (one to carry deoxygenated blood and other to carry oxygenated blood) Function of the cardiovascular system is to move oxygenated blood throughout the body and send deoxygenated blood back to the lungs Not all organisms need a circulatory system → some can use this method ^ to exchange gasses across the membrane `

heart, vessels, and blood BUT vessels spill content out into body Eg. worms that use simple diffusion to exchange gasses across the cell membrane

vessels never spill out, but constrict to let gasses escape Eg. Humans

We are big and have fast metabolisms that require more oxygen

Inferior vena cava → Right atrium → tricuspid valve → right ventricle → pulmonary valve → pulmonary artery → Lungs

Lungs → pulmonary vein → left atrium → mitral valve → left ventricle → aortic valve → aorta

Group of disorders of the heart and blood vessels referred to as heart disease and stroke

• Heart attacks are caused by a blockage of the coronary arteries. When the heart doesn’t receive oxygen due to a blockage in the artery it can cause some of the muscle cells to begin to die, what is called a myrocardial infarction. • Stroke is a blockage in the arteries to the brain that causes damage or death of brain tissue • Risk includes Smoking, High blood pressure, High cholesterol, Diabetes, Obesity

• Contractions can occur spontaneously because of a specialized group of myocardia (sets rhythm of heart and sits at atrium) • SA node regulates automatically, which also sends electrical impulse to walls of the atria (first little hump on normal sinus rhythm) • Impulse reaches AV node, which delays it (straight line stopping point on normal sinus rhythm) • Bundle branches carry signals from AV node to heart apex (sharp decline on normal sinus rhythm) • Signal spreads through ventricle walls, causing contraction (large spike then drop on normal sinus rhythm)

• First small bump: An electrical impulse travels from the sinoatrial node to the walls of the atria, causing them to contract • Flat line: the impulse reaches the atrioventricular node, which delays it • Decrease: bundle branches carry signals from the atrioventricular node to the heart apex • Apex: the signal spreads through the ventricle walls causing them to contract

it is evenly spaced on EKG and shows regular beats

complexes normal / even, but rate is <60 bpm

complexes normal / even, but rate is >100 bpm

baseline is irregular, ventricular response is irregular

rapid, wide irregular ventricular complexes

umbrella term for Atherosclerosis and Arteriosclerosis Has to do with an artery being thicker, harder, and less elastic ARTERIO- hardening of arterioles Can cause: ARTHERO: hardening from plaque in in endothelium Endothelium protects the vessel wall and prevents clotting Damage to it can occur from low density lipoprotein, smoking, and increased blood pressure Forms a fatty streak where platelets release growth factors that increase smooth muscle cells, which multiply and secrete collagen in the tunica media THIS leads to calcium crystals that would normally be deposited to stiffen arteries and stick where they are

Foam cells exposed, immediate blood clot Weakens artery walls (aneurysms) Kidneys think BP is low, activate the R-A-A system, and increase blood volume leading to hypertension Plaque breaks off → embolisms on the loose Atherosclerosis is an inflammatory disease through c reactive program, can act as a red flag that it’s happening sometimes this will crack, creating a blood crack , leading to less blood and downstream cell damage can occur

White blood cells, red blood cells, and plasma (water and protein), hemoglobin (inside the RBC)

Anemia is linked to red blood cell function, causing weakness, fatigue, and heart failure due to a lack of oxygen (red blood cells carry oxygen) Hemoglobin: red blood cells are essentially bags of hemoglobin Iron center containing heme pigment which can directly bind to 4 oxygen molecules Consists of 4 globin (2 alpha and 2 beta polypeptide chains) and four heme groups

Can be caused by: Destruction of bone marrow where RBCs are produced (less RBCs) Low iron in diet (less hemoglobin) Mutation in hemoglobin such as sickle cell disease (abnormal hemoglobin) Can be treated with: (depends on severity and cause) Injectable EPO Can be dangerous in regards to performance enhancing drugs Iron supplements Blood transfusion

O2– low affinity means there is more O2 leaving, and increased CO2 uptake CO2– there is more co2 in the blood makes the blood more acidic, which changes its shape to further lower affinity

Erythropoietin (EPO) → kidney receptors detect low levels, signal kidneys to produce more EPO, which causes hematocrit to rise and an increase in RBC production

Hemostasis: The process that stops bleeding at the site of an injury while maintaining normal blood flow elsewhere in the circulation Vascular spasm & platelet plug Step 1: Vascular spasm - smooth muscle contracts, causing vasoconstriction Step 2: Platelet plug formation - injury to the lining of vessel exposes collagen fibers; platelets adhere Platelets release chemicals that make nearby platelets sticky; platelet plug forms Step 3: Coagulation - fibrin forms a mesh that traps red blood cells and platelets, forming the clot