Human Bio Chapter 5: Cardiovascular system and Chapter 6: Blood

Cardiovascular system

The heart and blood vessles

Function: transport

Oxygen to cells, remove CO2 and other metabolism waste products, nutriets from digestive system to endocrime system

Function: Homeostasis

maintain temp, pH balance, water and electrolyte levels

Lymphatic system function

Collects excess insterstitial fluid and returns it to the cardiovascular system

Artery

A blood vessel that carries oxygenated blood away from the heart to various parts of the body.

Endothelium

A thin layer of cells lining the blood vessels, providing a smooth surface for blood flow and regulating vascular functions. Innermost layer of the artery

Layers of the artery

Endothelium, smooth muscle and elastic tissue, connective tissue

Arterioles

Small blood vessels that branch from arteries and lead to capillaries, regulating blood flow and pressure.

Capillaries

Smallest blood vessels where gas, nutrient, and waste exchange occurs between blood and tissues.

Precapillary sphincters

Rings of muscle that control the blood flow through a capillary bed

Arteriovenous shunt

A connection between an artery and a vein that allows blood to bypass capillaries, often helping to regulate blood flow and pressure in certain areas.

Veins

Blood vessles that return blood to the heart

Venules

Small veins that drain blood fromt he capillaries then join to form a vein. Have the same three layers as the arteries, but thinner

Myocardium

The interior wall of tissue in the heart, consists mostly of cardiac muscle tissue

Pericardium

A thick, membranous sac that supports and protects the heart

Pericardial fluid

Fluid found between the layers of the pericardium that reduces friction during heartbeats.

Septum

A muscular wall that divides the left and right sides of the heart, preventing the mixing of oxygenated and deoxygenated blood.

Four chambers of the heart

Left atrium, right atrium, right vetricle, left ventricle

Atrioventricular valves

Valves located between the atria and ventricles of the heart, preventing backflow of blood during contraction.

Chordae tendineae

Fibrous cords that connect the atrioventricular valves to the heart muscles, ensuring proper valve function during the cardiac cycle.

Tricuspid valve

Right AV valve; has three flaps

Mitral valve

Left AV valve; has two flaps.

Semilunar valves

Remaining two valves with flaps shaped like half-moons. Lie between the vantricles and attached vessles

Coronary arteries

Blood vessels that supply oxygen-rich blood to the heart muscle. They branch off from the aorta and encircle the heart.

Vena cava

Carry oxegen-poor blood from systemic veins to the right atrium

Each heartbeat is called a _____

cardiac cycle

Systole

the phase of the cardiac cycle when the heart muscle contracts and pumps blood out of the chambers.

Diastole

The resting phase of the cardiac cycle

Sinoatrial node

Located in the upper dorsal wall of the right atriumm, the sinoatrial node is known as the heart's natural pacemaker, initiating electrical impulses that regulate the heartbeat.

Atrioventricular

Located in the base of the right atrium very near the septum, gets signal from SA node then goes

Electrocardiogram (ECG)

A recording of the electrical changes that occur in the myocardium during a cardiac cycle

Blood pressure

the pressure of blood against the wall of a blood vessel

Systolic pressure

The highest arterial pressure, reached during ejection of blood from the heart

Diastolic pressure

The lowest arterial pressure, occurs when heart ventricles are relaxing

Blood pressure units

mmHg

Hypertension

High blood pressure

Hypotension

Low blood pressure

Pulmonary circut

Circulates blood through the lungs

Systemic circut

Serves the needs of the body tissues

Aorta

The largest artery in the systemic circut

Venae cavae

Largest veins in the systemic circut

Hepatic portal vein

Drains blood from the capillary beds of the digestive tract and carries it to a capillary bed in the liver

Lymph

Interstitial fluid within lymphatic vessels

Atherosclerosis

Caused by the formation of lesions (atherosclerotic plaques) on the inside of blood vessles

Thromboembolism

A clot first carried in the bloodstream that then becomes completely stationary when it lodges in a small blood vessel

Cerebrovascular accident (CVA) aka a stroke

Usually caused by a small cranial arteriole burst or blockage by an embolus, lack of oxygen causes a part of the brain to die

Myocardial infarction (MI) aka a heart attack

Portion of the heart muscle dies due to lack of oxygen

Anigina pectoris

Coronary artery becomes partially blocked, usually results

Anuerysm

A ballooning of a blood vessel

Antibody

a protein that disables specific pathogens

Phagocytosis

Blood cells engulfing and destroying pathogens

The body’s pH

7.4

The formed elements are ___

red blood cells, white blood cells, and platelets

Water makes up about ___ of plasma

91%

Three major types of plasma proteins

albumins, globulins, and fibrinogen

Hemoglobin (Hb)

Iron-containing pigment in red blood cells that combines with and transports oxygen.

Forms when oxygen binds to heme in the lungs

oxyhemoglobin

When heme gives up the oxygen in the tissues

deoxyhemoglobin

Hemoglobin carrying carbon dioxide.

carbaminohemoglobin

hemolysis

Rupture of red blood cells accompanied by the release of hemoglobin.

3 granular leukocytes

Neutrophils, Eosinophils, and Basophils

2 Agranular leukocytes

Lymphocytes and Monocytes

Neutrophils function

Phagocytize pathogens and cellular debris, account for 50-70% of adult white blood cells

Eosinophils function

Use granule contents to digest large pathogens such as worms, protect the body against large parasites

Basophils function

Promote blood flow to injured tissues and the inflammatory response, rarest of white blood cells

Lymphocytes function

Responsible for specific immunity; B cells produce antibodies and T cells destroy cancer and virus-infected cells

Monocytes function

Become macrophages that phagocytize pathogens and cellular debris

Types of white blood cells

Granular leukocytes or agranular leukocytes

Granular leukocytes

Contain noticeable cytoplasmic granules that can be viewed under a microscope

Agranular leukocytes

Contain sparse fine granules that cannot be easily viewed under a microscope

Platelets

fragments of large cells

Process of a blood clot forming

Puncture → platelets form a plug → prothrombin activator released and initiated a cascade of enzymatic reactions → fibrin threads form and trap blood cells

insufficient number of platelets, due to production or breakdown

thrombocytopenia

Thromboembolism

A blood vessel blocked by a blood clot

Hemophilia

an inherited clotting disorder that causes a deficiency in a clotting factor