Set 1: Cardiac Cycle, Hem

What mechanical event does the 'a wave' correspond to?

Right atrial contraction.

What mechanical event does the 'c wave' correspond to?

Tricuspid valve closure at the start of ventricular systole.

What mechanical event does the 'x descent' correspond to?

Atrial relaxation and the tricuspid valve being pulled down.

What mechanical event does the 'v wave' correspond to?

Atrial filling.

What mechanical event does the 'y descent' correspond to?

Tricuspid valve opening and the atrium emptying.

What are the characteristics and locations of Continuous capillaries?

Found in Muscle, Nerve, and Connective tissue; they are the least permeable.

What are the characteristics and locations of Fenestrated capillaries?

Found in Renal glomeruli and Endocrine glands; they allow for high filtration.

What are the characteristics and locations of Sinusoidal (Discontinuous) capillaries?

Found in Liver and Bone Marrow; they are the most permeable, allowing proteins through.

What is the formula for Net Filtration Pressure?

(P_C-P_{IF})-(\pi_P-\pi_{IF}).

Where is capillary filtration favored?

At the arterial end (where Capillary Hydrostatic Pressure P_C is 35 mmHg).

Where is capillary absorption favored?

At the venous end (where P_C drops to 15 mmHg).

What are the three main mechanisms that cause edema?

Occurs when P_C increases (hypertension/heart failure), Plasma Oncotic Pressure drops (malnutrition/liver disease), or Lymphatic obstruction occurs.

How is Cardiac Output conceptually defined?

The total path taken per unit time.

What is Preload (Venous Return)?

The "wind blowing from behind"—helps the heart pump more without extra effort.

What is Afterload (Arterial Pressure)?

The "steep and rough road"—resistance the heart must overcome.

What is Inotropy?

The physical force the cyclist exerts on the pedals.

What is the standard formula for Cardiac Output (CO)?

CO=Stroke\ Volume\ (SV)\times Heart\ Rate\ (HR).

What is the Fick Method formula for Cardiac Output?

CO=([O_2]{left\ heart}-[O_2]{right\ heart})/O_2\ used.

What is the Frank-Starling Law?

Higher End-Diastolic Volume (EDV) stretches cardiac muscle fibers, increasing the force of contraction and SV.

What happens to Stroke Volume if EDV exceeds 300 ml?

SV begins to decrease (danger zone).

On a P-V loop, what event marks the start of Isovolumetric Contraction (Point b)?

Mitral Valve Closes.

On a P-V loop, what event marks the start of Ejection (Point C)?

Aortic Valve Opens.

On a P-V loop, what event marks the start of Isovolumetric Relaxation?

Aortic Valve Closes.

On a P-V loop, what event marks the start of Filling Diastole (Point a)?

Mitral Valve Opens.

How does the myocardium generate ATP at rest?

It uses Glucose, Free Fatty Acids, and Lactate equally (approx. 1/3 each).

How does the myocardium generate ATP during exercise?

Utilization shifts heavily toward Lactate (approx. 2/3), which is absorbed from the blood as it is produced by active skeletal muscles.

Why must coronary blood flow increase to deliver more oxygen to the heart?

The heart has an extremely high oxygen extraction coefficient (0.70-0.80) even at rest, meaning it cannot simply extract more from the same blood.