Topic: The Cardiovascular System Main Functions * Transports oxygen, nutrients, hormones, and waste products * Helps regulate body temperature * Maintains homeostasis * Protects against infection through white blood cells ⸻ Heart Anatomy Chambers of the Heart 1. Right Atrium * Receives deoxygenated blood from the body 2. Right Ventricle * Pumps blood to the lungs through the pulmonary artery 3. Left Atrium * Receives oxygenated blood from the lungs 4

Topic: The Cardiovascular System

Main Functions

  • Transports oxygen, nutrients, hormones, and waste products

  • Helps regulate body temperature

  • Maintains homeostasis

  • Protects against infection through white blood cells


Heart Anatomy

Chambers of the Heart

  1. Right Atrium

    • Receives deoxygenated blood from the body

  2. Right Ventricle

    • Pumps blood to the lungs through the pulmonary artery

  3. Left Atrium

    • Receives oxygenated blood from the lungs

  4. Left Ventricle

    • Thickest chamber; pumps blood to the body through the aorta


Blood Flow Pathway

Body → Superior/Inferior Vena Cava → Right Atrium → Tricuspid Valve → Right Ventricle → Pulmonary Valve → Pulmonary Artery → Lungs → Pulmonary Veins → Left Atrium → Mitral Valve → Left Ventricle → Aortic Valve → Aorta → Body


Important Vocabulary

  • Cardiac Muscle — involuntary muscle found only in the heart

  • Stroke Volume — amount of blood pumped per beat

  • Cardiac Output — amount of blood pumped per minute

  • Systole — contraction phase

  • Diastole — relaxation phase


Blood Pressure

Normal adult BP:
120/80 mmHg

  • Systolic = pressure during ventricular contraction

  • Diastolic = pressure during relaxation

Factors affecting BP:

  • Stress

  • Exercise

  • Diet (especially sodium)

  • Hydration levels


Blood Vessels

Arteries

  • Carry blood away from heart

  • Thick muscular walls

  • Usually oxygenated

Veins

  • Carry blood toward heart

  • Contain valves to prevent backflow

  • Usually deoxygenated

Capillaries

  • Site of gas and nutrient exchange

  • One-cell-thick walls


ECG Notes

P wave = atrial depolarization
QRS complex = ventricular depolarization
T wave = ventricular repolarization

Tachycardia = HR above 100 bpm
Bradycardia = HR below 60 bpm


Quick Mnemonics

  • LAB RAT
    Left Atrium → Bicuspid → Left Ventricle
    Right Atrium → Tricuspid

  • “Arteries Away”
    Arteries carry blood away from the heart


Clinical Correlations

  • Atherosclerosis = plaque buildup in arteries

  • Myocardial infarction = heart attack

  • Hypertension can damage vessels over time