7. the cardiac cycle

7/31/2019 7. the Cardiac Cycle

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The cardiac cycleDescribing the sequence of

events in one heart beat
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Set Induction

Song on cardiac cycle

http://www.youtube.com/watch?v=xVofKd

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http://www.youtube.com/watch?v=xVofKdXOa4Mhttp://www.youtube.com/watch?v=xVofKdXOa4Mhttp://www.youtube.com/watch?v=xVofKdXOa4Mhttp://www.youtube.com/watch?v=xVofKdXOa4M


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KWLH for Cardiac cycle

K - Stands for helping students recallwhat they KNOW about the subject.

W - Stands for helping students

determine what they WANT to learn. L - Stands for helping students

identify what they LEARN as theyread.

H - Stands forHOW we can learnmore (other sources where additional

information on the topic can be

found).


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Sample KWLH

What We Know What We Want toFind Out

What We Learned How Can WeLearn More

Dinosaurs are

large.

Dinosaurs are

dead.They lived a long

time ago.

There is a movie

about dinosaurs

How long ago did

they live?

Why did they die?

How do we knowwhat they looked

like?

Who are the

people who study

dinosaurs?

An archeologist

has an exciting

life.

Dinosaurs eatplants and some

eat meat.

Some dinosaurs

were gigantic, but

had small brains.

Fossils uncoverdinosaur traits.

Research

Museums

Field Trips

Archeological digsVideos

Internet computer

search


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Cardiac cycle - Animation

http://www.interactivephysiology.com/dem

o/systems/buildframes.html?cardio/cardcy

cl/01

http://bcs.whfreeman.com/thelifewire/conte

nt/chp49/49020.html
http://www.interactivephysiology.com/demo/systems/buildframes.html?cardio/cardcycl/01http://www.interactivephysiology.com/demo/systems/buildframes.html?cardio/cardcycl/01http://www.interactivephysiology.com/demo/systems/buildframes.html?cardio/cardcycl/01http://bcs.whfreeman.com/thelifewire/content/chp49/49020.htmlhttp://bcs.whfreeman.com/thelifewire/content/chp49/49020.htmlhttp://bcs.whfreeman.com/thelifewire/content/chp49/49020.htmlhttp://bcs.whfreeman.com/thelifewire/content/chp49/49020.htmlhttp://bcs.whfreeman.com/thelifewire/content/chp49/49020.htmlhttp://bcs.whfreeman.com/thelifewire/content/chp49/49020.htmlhttp://www.interactivephysiology.com/demo/systems/buildframes.html?cardio/cardcycl/01http://www.interactivephysiology.com/demo/systems/buildframes.html?cardio/cardcycl/01http://www.interactivephysiology.com/demo/systems/buildframes.html?cardio/cardcycl/01


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Definitions

Systole = period of ventricular contraction.

Diastole = period of ventricular relaxation.

NOTE: Normally diastole is longer than

systole.


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Cardiac cycle

General Principles.

Contraction of the myocardium generatespressure changes which result in the orderlymovement of blood.

Blood flows from an area ofhigh pressure to anarea oflow pressure, unless flow is blocked bya valve.

Events on the right and left sides of the heart arethe same, but pressures are lower on the right.


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Atrial systole

The heart is full of bloodand the ventricles arerelaxed

Both the atria contractand blood passes downto the ventricles

The atrio-ventricularvalves open due to bloodpressure

70% of the blood flowspassivelydown to theventricles so the atria donot have to contract agreat amount.


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Ventricular systole

The atria relax.

The ventricle wallscontract, forcing the

blood out The pressure of the

blood forces the atrio-ventricular valves to

shut (producing theheart sound lub)


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Ventricular systole

The pressure of

blood opens the

semi-lunar valves.

Blood passes into

the aorta and

pulmonary arteries.


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Diastole

The ventricles relax

Pressure in the ventriclesfalls below that in thearteries

Blood under highpressure in the arteriescauses the semi lunarvalves to shut. Thisproduces the secondheart sound, dub.

During diastole, all themuscle in the heartrelaxes.


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Blood from the vena

cava and pulmonary

veins enter the atria.

The whole cyclestarts again.


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Cardiac Cycle:

Pressure Changes in the heart

Set Induction : Recall of cardiac cycle

Complete the table below to summarise

cardiac cycle.

Phase of cardiac

cycle

Atrial chambers

Contract/relax

Fill /empty

From/to

Ventricular

chambers

Contract/relax

Fill /empty

From/to

AV valve

Open/close

SL valves

Open /close


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Match the letter on the

graph to thefollowing events

Semi-lunar valves open

Atrio-ventricular valvesclose,

Semi-lunar valves

close

Atrio-ventricular valves

open

Plenary Cardiac cycle


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atrio-ventricular valves open


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atrio-ventricular valves openatrio-ventricular valves close


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semi-lunar valves open


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semi-lunar valves open

semi-lunar valves close


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Control of the heart beat and ECG

http://www.phschool.com/science/biology_

place/biocoach/cardio1/electrical.html

http://www.nhlbi.nih.gov/health/dci/Diseas

es/hhw/hhw_electrical.html

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ata/imports/HTML/lifebeatonline/summer2

004/learning.shtml
http://www.phschool.com/science/biology_place/biocoach/cardio1/electrical.htmlhttp://www.phschool.com/science/biology_place/biocoach/cardio1/electrical.htmlhttp://www.nhlbi.nih.gov/health/dci/Diseases/hhw/hhw_electrical.htmlhttp://www.nhlbi.nih.gov/health/dci/Diseases/hhw/hhw_electrical.htmlhttp://www.bostonscientific.com/templatedata/imports/HTML/lifebeatonline/summer2004/learning.shtmlhttp://www.bostonscientific.com/templatedata/imports/HTML/lifebeatonline/summer2004/learning.shtmlhttp://www.bostonscientific.com/templatedata/imports/HTML/lifebeatonline/summer2004/learning.shtmlhttp://www.bostonscientific.com/templatedata/imports/HTML/lifebeatonline/summer2004/learning.shtmlhttp://www.bostonscientific.com/templatedata/imports/HTML/lifebeatonline/summer2004/learning.shtmlhttp://www.bostonscientific.com/templatedata/imports/HTML/lifebeatonline/summer2004/learning.shtmlhttp://www.nhlbi.nih.gov/health/dci/Diseases/hhw/hhw_electrical.htmlhttp://www.nhlbi.nih.gov/health/dci/Diseases/hhw/hhw_electrical.htmlhttp://www.nhlbi.nih.gov/health/dci/Diseases/hhw/hhw_electrical.htmlhttp://www.phschool.com/science/biology_place/biocoach/cardio1/electrical.htmlhttp://www.phschool.com/science/biology_place/biocoach/cardio1/electrical.html


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Aberrant ECG patterns indicate damage


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Valves of the Heart


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Papillary Muscles

The papillary muscles attach to the lower portion ofthe interior wall of the ventricles.

They connect to the chordae tendineae, which

attach to the tricuspid valve in the right ventricle and

the mitral valve in the left ventricle.

The contraction of the papillary muscles opens

these valves. When the papillary muscles relax, thevalves close.

Chordae Tendineae

The chordae tendineae are tendons linking the

papillary muscles to the tricuspid valve in the right

ventricle and the mitral valve in the left ventricle

. As the papillary muscles contract and relax, thechordae tendineae transmit the resulting increase

and decrease in tension to the respective valves,

causing them to open and close.

The chordae tendineae are string-like in

appearance and are sometimes referred to as

"heart strings.

Valves of the Heart


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Cardiac Muscle

7. the cardiac cycle

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