MICRO LAB- Heart & Vessels

Heart Structures I need to know

Interventricular septum

Interatrial septum

Apex

Base

Chordae tendineae

Ligamentum arteriosum

Interventricular sulcus

Atrioventricular sulcus

Chambers

Right atrium

Left atrium

Right ventricle

Left ventricle

Valves

Left Atrioventricular (AV)

Bicuspid/Mitral

Right Atrioventricular (AV)

Tricuspid

Left Semilunar

Aortic/Aortic Semilunar

Right Semilunar

Pulmonary/Pulmonary Semilunar

Vessels

Superior vena cava

Inferior vena cava

Pulmonary artery/trunk

Pulmonary veins

Aorta (aortic trunk/artery)

Coronary vessels

Right coronary artery

Left coronary artery

Circumflex artery

Anterior interventricular artery

Posterior interventricular artery

Marginal artery

Great cardiac vein

Coronary sinus

Layers of the heart

Endocardium/Endothelium

Myocardium

Epicardium/Visceral pericardium

Pericardial space

Pericardial fluid

Parietal pericardium

Fibrous Pericardium

Mediastinum

Other vocabulary

Pulmonary circulation

• The pathway that carries deoxygenated blood from the right side of the heart to the lungs for gas exchange and returns oxygenated blood to the left atrium. Arteries are blue

Systemic circulation

• The pathway that sends oxygenated blood from the left side of the heart to all tissues of the body and returns deoxygenated blood to the right atrium. Arteries are red

Coronary circulation

• The network of coronary arteries and veins that supply the heart muscle (myocardium) itself with oxygen and nutrients and remove wastes

Heart

• ❤ Heart Structure & Blood Flow

  • Right atrioventricular (tricuspid) valve → blood goes to the lungs (pulmonary circuit).

  • Left atrioventricular (bicuspid/mitral) valve → blood goes to the rest of the body (systemic circuit).

  💪 Atria vs. Ventricles

  • Atria

    • Weak pumps

    • They fill before they contract

    • Lowest pressure chambers

  • Ventricles

    • Main pumps of the heart

    • Generate much higher pressure

    • Left ventricle = highest pressure in the body

  🚪 Heart Valves

  • Valves are controlled by blood flow and pressure, not muscles.

  • AV valves:

    • Tricuspid (right)

    • Bicuspid/Mitral (left)

    • Stabilized by chordae tendineae + papillary muscles

  • Semilunar valves:

    • Pulmonary valve

    • Aortic valve

    • Control blood leaving the heart

Heart pt 2

• ⚡ Cardiac Conduction System

  • SA node = pacemaker; fires action potentials first

  • AV node = slows the signal so ventricles fill

  • Depolarization → contraction

  • Repolarization → relaxation

  🫀 Cardiac Cycle

  • Atrial systole = atria contract

  • Ventricular systole = ventricles contract

  • Diastole = all chambers relax

  🩸 Blood Vessels & Pressure

  • Arteries

    • Carry blood away from the heart

    • High pressure → this is where blood pressure is measured

  • Veins

    • Carry blood toward the heart

    • Low pressure

    • Connect to atria

  📈 Heart Rate, Blood Pressure, and Blood Flow

  • When heart rate increases → blood pressure increases → blood flow increases

  • Vasoconstriction

    • Blood pressure increases

    • Blood flow to that area decreases

  • If HR increases and vasoconstriction happens at the same time:

    • BP increases a lot

    • Blood flow redistributes and balances based on need

The strongest chambers of the heart are the ________ because they both pump blood _________

Ventricles; away from the heart

semilunar valves are between

ventricles and arteries

The cardiac conduction system is made up of ________ tissue

muscular

Heart sounds result directly from

closing of the heart valves

What contains oxygenated blood?

left atrium and ventricle

Both arteries and veins have what structural feature in common

three layered walls

Because __________ carry blood __________ the heart, their structure/function is designed to aid in ensuring blood doesn’t flow backwards

veins; toward

Which layer of the arterial wall is responsible for vasoconstriction?

tunica media

Elastic arteries function as

pressure or energy reservoirs