Exam 4- Focus Points Flashcards
Heart Location
The heart is positioned in the mediastirnum within the thoracic cavity, providing central access for efficient blood distribution.
End-Diastolic Volume (EDV)
This is the volume of blood in a ventricle at the end of diastole (just before the heart contracts). It’s about 120-130 mL of blood.
End-Systolic Volume (ESV)
This is the volume of blood remaining in a ventricle after it has contracted (end of systole). Roughly 50-60 mL of blood.
Stroke Volume (SV))= EDV−ESV= 70ml= Blood Ejection per Contraction:
Each chamber of the heart pumps about 70 mL of blood with every beat in a resting adult.
Cardiac Output (CO
The volume of blood the heart pumps per minute and is calculated: Cardiac Output (CO)=Heart Rate (HR)×Stroke Volume (SV)= Around 5 L/min.
Pulmonary Circuit Purpose
The pulmonary circuit directs deoxygenated blood to the lungs to receive oxygen before returning to the heart
Right Atrium Function:
The right atrium receives venous blood from the body via the superior and inferior venae cavae.
Left Atrium Function
The left ventricle receives oxygenated blood from the left atrium and pumps it through the aorta to supply the body’s organs and tissues.
Ventricles functions (right and left)
Pericardium Function:
The pericardium surrounds and protects the heart, preventing friction and infection.
Visceral Pericardium Location:
The visceral pericardium, also called the epicardium, is the layer directly adhered to the heart’s outer surface.
Cause of Cardiac Tamponade:
Cardiac tamponade is caused by fluid accumulation in the pericardial cavity, which compresses the heart.
Tricuspid Valve Location:
The tricuspid valve is situated between the right atrium and right ventricle, preventing backflow of blood.
Aortic Valve Function
The aortic semilunar valve prevents blood from flowing back into the heart from the aorta.
Sinoatrial (SA) Node Role
The sinoatrial (SA) node is the natural pacemaker, initiating the heart’s electrical impulses and regulating rhythm.
Intercalated Discs in Cardiac Muscle:
Intercalated discs connect cardiac muscle cells, allowing coordinated contraction of the heart.
Cardiac Output Definition:
Cardiac output is the volume of blood each ventricle pumps per minute, a key measure of heart function.
Types of Shock:
Major types of shock include:
* hypovolemic (caused by blood loss)
* –cardiogenic (due to heart failure)–
* –septic (infection-induced)–
* anaphylactic (severe allergic reaction).
EKG Wave Correspondence
- P wave: atrial depolarization (Smallest hump)
- QRS complex: ventricular depolarization (largest one)
- T wave: ventricular repolarization (Small-medium)
Blood’s Primary Function:
Blood transports oxygen and essential nutrients to cells throughout the body.
Plasma Composition of Blood:
: Plasma, the largest component of blood, serves as the medium for transporting nutrients, hormones, and waste.
Hematocrit Purpose:
Hematocrit measures the percentage of red blood cells in blood, indicating oxygen-carrying capacity.
Leukocytes’ Role in Immunity
Leukocytes, or white blood cells, protect the body against infections and foreign invaders.
Origin of Blood Cells
All blood cells originate from multipotent stem cells in the bone marrow.
Role of Erythropoietin (EPO)
EPO is a hormone that stimulates red blood cell production, especially in response to low oxygen levels.
Erythrocyte Lifespan
Red blood cells, or erythrocytes, have an average lifespan of around 120 days.
Ferritin in Iron Storage:
Ferritin is an iron-storage protein in the liver, crucial for supplying iron needed for red blood cell production.
Definition of Anemia
Anemia is a condition characterized by a deficiency in red blood cells or hemoglobin, reducing oxygen delivery
Characteristics of Polyethemia
Polycythemia is an abnormally high red blood cell count, which increases blood viscosity and cardiovascular strain.
Role of Lymphocytes:
Lymphocytes are white blood cells involved in adaptive immunity, targeting specific pathogens.
Immunoglobulin Types and Roles
Immunoglobulin classes include:
* –IgE (involved in allergies)–
* IgA (found in mucosal areas)
* IgM (first antibody response)
* –and IgG (provides long-term immunity).–
Innate immunity vs Adaptive immunity (T= cellular and B lymphocytes= Homoral)
Role of Platelets in Clotting
Platelets are essential in blood clotting, forming plugs to prevent excessive bleeding.
First Step of Hemostasis:
Hemostasis begins with vascular spasm, which constricts blood vessels to minimize initial blood loss.
Fibrin’s Role in Clotting
Fibrin forms a mesh in a blood clot, stabilizing it to secure the wound site
Cause of Hemophilia
Hemophilia is a genetic disorder caused by insufficient clotting factors, leading to excessive bleeding.
Arteries vs. Veins:
Arteries carry oxygenated blood away from the heart under high pressure, while veins return blood to the heart.
Function of Capillaries
Capillaries are tiny vessels where nutrient and gas exchange occur between blood and tissues.
Unique Feature of Veins:
Veins have valves that prevent backflow, aiding the return of blood to the heart, especially in low-pressure areas.
Pressure in Arteries:
Arteries experience the highest blood pressure as they carry blood directly from the heart’s forceful contractions.
Measuring Blood Pressure
Blood pressure is typically measured with a sphygmomanometer, reflecting the force of blood against arterial walls.
Mean Arterial Pressure (MAP):
: MAP is the average arterial pressure driving blood flow to tissues, crucial for organ perfusion. Also BP Systolic and Diastolic, and Pulse Pressure
Vessel Compliance:
Compliance is the ability of blood vessels to expand under pressure, allowing stable blood flow.
Impact of Arteriosclerosis
Arteriosclerosis reduces vessel compliance, leading to increased blood pressure and cardiovascular strain.
Hepatic Portal System Function:
: The hepatic portal system directs blood from the digestive organs to the liver for processing and detoxification.
