Physiology Vocabulary

Vocabulary terms seen from labs about cardiovascular system and lungs.

Sino-Atrial Node

A node that generates electrical signals, causing the atria to contract. It acts as the heart’s normal peacemaker and controls heart rate.

Depolarization

When a cell has an electric charge shift, making the inside of it less negative compared to the outside. Occurs during influx of Na+ ions.

Bi-polar Lead

2 leads placed on each wrist and one on the ankle to make up the “Einthoven Triangle.” Any information obtained is known as bipolar.

P, Q, R, S, T waves

Electrical events of the heart in ECG. The P wave represents atrial depolarization, the QRS complex corresponds to ventricular contraction after the atria contracts, and the T wave corresponds to ventricle repolarization. In the QRS complex, the Q wave is a negative deflection showing early depolarization, the R wave is positive showing main part of ventricles activated, and the T wave is the last depolarization face.

Mean Electrical Axis of the Heart

Represents the average direction of the heart’s electrical activity during ventricular depolarization. Changes when laying down from 0 degrees to 90 degrees when standing up

Arrhythmia: (Respiratory Arrhythmia)

Variability in the heart rate where it is faster when inhaling and slower when exhaling.

Systole and Diastole

Systole is when the heart contracts to pump blood and diastole is when the heart relaxes

Systole:

A contraction in the heart that happens between the S1 and S2 sounds of the heart. Represents a contraction.

Diastole

Occurs when the heart muscles are relaxed and allow blood to enter the chambers.

Orthostatic BP (blood pressure)

The change in blood when a person stands up after being in a laying down position. The blood pressure significantly drops.

Baroreceptors

Sensory neurons that sense changes in blood pressure and send them to the brain.

Sphygmomanometer

A tool used to measure blood pressure by stopping blood flow in the artery.

Aerobic & Anaerobic:

2 Different types of cellular respiration

Aerobic Respiration

Cellular respiration that occurs in the presence of oxygen. It breaks down food molecules to produce energy.

Anaerobic Respiration

Cellular respiration that does NOT use oxygen to produce energy. ATP energy is produced without oxygen.

Cardiac Output

Shows the amount of blood pumped by the heart per minute and is calculated using CO = HR X SV

Stroke Volume

Amount of blood Amount of blood that leaves the heart’s left ventricle during each contraction

Tidal Volume (TV)

Normal breathing. Amount of air that is breathed in and out during normal relaxed breathing

Inspiratory reserve volume (IRV)

The extra amount of air a person can forcefully inhale beyond a normal breath

Expiratory reserve volume (ERV

The extra amount of air a person can forcefully exhale beyond a normal exhalation

Inspiratory capacity

maximum amount of air that can be inhaled after normal exhalation

Expiratory capacity

Maximum amount of air that can be exhaled after normal inhalation

Vital capacity

The maximum amount of air a person can forcefully expel from lungs after taking a veryy deep breath. VC = IRV + ERV + TV.

Total Lung Capacity (TLC)

The maximum volume of air that the lungs can hold after a forceful inhalation. Encompasses all lung volumes. TLC = IRV + ERV + TV + RV

Residual Volume

The amount of air that REMAINS in the lungs after exhaling as forcefully as possible

Forced Expiratory Volume (FEV1, FEV2, and FEV3)

The total volume of air exhaled forcibly after taking a deep breath. The 3 parts are FEV1, FEV2, and FEV3 which represent the amount of air expelled at 1 second, 2 seconds, and 3 seconds respectively.

P wave

Represents atrial depolarization

QRS Complex

Ventricular contraction after the atria contracts.

T Wave

Corresponds to ventricle repolarization. It is the last (repolarization) face.

Q wave

Negative deflection showing early depolarization,

R wave

Is positive and shows main part of ventricles are activated