Semester 2 L13 : The Cardiovascular System 2 – Electrical and Mechanical Events Flashcards
what does Excitation cause chambers to do?
contract
beating of a heart allows a body to do what?
pump blood through the heart
what happens first systole of diastole?
diastole, systole is the last stage of a heart beat.
what is systole?
Action potential causes chamber to contract and eject blood
what is Diastole?
when the chamber relaxes and fills with blood
what happens in the ventricular filling phase?
- Atrium is diastole and is filled
- Atrioventricular valve is open with high pressure in the atrium
- The ventricle is diastole and is filling via draining
- The semilunar valve is closed and there’s high pressure in the artery
return to
slide 5
during systole blood is forced through what to what?
From atrium to ventricle
From ventricle to artery
why does the heart muscle contract?
due to action potential running through heart
where do action potentials start?
Action potential starts at the sinoatrial node
cardiac muscle is ______.
striated
what holds together cardiac myocytes ?
intercalated discs
are cardiac mycocytes aligned?
no
cardiac muscle has a ____ _____ per cell.
- single
2. nucleus
Individual ______ are not regularly aligned
sarcomeres
what similarity does cardiac and skeletal muscle have?
they are both striated
what do pacemaker cells generate?
electrical impulses
what is a sarcomere?
section between two Z lines, and is divided into zones or bands.
When the muscle contracts the ___ zone and ___ band _____ as the thin (actin) filaments are brought ____ together, the ___ band remains the same length.
- H
- I
- shorten
- closer
- A
Movement of ions across the plasma membrane result in what?
an electrical charge
what is passive transport?
Diffuse down the concentration gradient
what do ion channels and carrier proteins do?
Create holes in the membrane allowing movement
does active transport go against or with the concentration gradient?
against the concentration gradient
for every ATP molecule how many Na ions are pumped out and how many potassium ions are pumped in in?
3x Sodium ions pumped out
2x Potassium ions pumped in
