Exam 1: BIOS 255 BIOS255 Latest

Exam 1: BIOS 255 / BIOS255 (Latest

Update 2025 / 2026) Anatomy and Physiology III with Lab | Questions with Answers | Grade A | 100% Correct - Chamberlain

Question:

function of WBC's

Answer:

defend the body against infections and foreign substances

Question:

what ions move through the membrane of cardiac muscle cells during heart action potential?

Answer:

sodium ions, calcium ions, potassium ions

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Question:

what do sodium ions do during heart action potential?

Answer:

causes membrane potential to become more positive quickly

Question:

what do calcium ions do during heart action potential?

Answer:

facilitate the contraction of the heart muscle during the plateau phase

Question:

what do potassium ions do during heart action potential?

Answer:

helps return the membrane potential back to resting by moving out of the cell

Question:

P wave in an ECG/EKG

Answer:

represents atrial depolarization; happens when electrical impulse spreads thru the atria causing them to contract and push blood into the ventricles 2 / 3

Question:

QRS complex of ECG/EKG

Answer:

represents ventricular depolarization; happens when the ventricles contract

Question:

T wave of ECG/EKG

Answer:

represents ventricular repolarization; happens when the ventricles relax

Question:

PR interval in ECG/EKG

Answer:

time it takes impulses to travel from atria to ventricles

Question:

QT interval in ECG/EKG

Answer:

time it takes ventricles to contract and relax

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