TOPIC: Valves & Coronary Circulation OBJ: 7,9

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HW: Heart packet Pg. 426 &429 DUE: Friday

DO NOW: 3- What are your concerns for the heart practical?

Phones and Wireless headphones in

assigned pockets please

HANDOUTS to PICK-UP:

-practice packet

-Notes 18.2-18.3

-Work on heart video [due Tuesday 1/21/2020]

REMINDERS-Job Shadow/Volunteer [1st deadline: 2/3/2020]

Add on to each QUESTION every night as REVIEW

18.2- HEART VALVES & BLOOD FLOW IN ONE DIRECTION

7- -NAME the four heart valves and for each describe their location, function, and mechanism of operation.

18.3- BLOOD FLOW [PATHWAY] THROUGHOUT THE BODY

8- -TRACE the pathway of blood through the heart starting with the superior/inferior vena cava.

For Exam: Be able to start anywhere!

Anatomy Daily Work Tracker

1 1/8 Heart Labeling: Pg 419 & 421 1/9

2

3

18.3 Blood Flow

Sheep Packet: highlight

4

5

1/10

1/13

1/13

1/14

Heart labeling: Pg 426 & 4296 1/15 1/17

Have neighbor check off

& initial in PEN

BLUE highlight → you should have 2, 1, or 0 checked

1/9 Heart Labeling: Pg 423 & 425 1/10

1/9 1/10External Heart Coloring

HANDOUT-Due Date: January 20th, 2020-Paper with notes/signature due January 21st, 2020-All structures listed must be named/labeled in the video

20-7

18.2 Heart Valves

Allow blood to flow in only one direction

•Four valves

•Atrioventricular valves – between atria and ventricles

•Papillary muscles: attached to chordae tendineae to help prevent

valves from allowing backflow

•Bicuspid valve (left AV) – aka. Mitral valve

•Prevents backflow of bld into Left Atrium

•LAMB pneumonic

•Tricuspid valve (right AV)

•Prevents backflow of bld into Right Atrium

20-8

18.2 Heart Valves-AV valves open

• A-V valves open and allow blood to flow from atria into

ventricles when ventricular pressure is lower than atrial pressure

– occurs when ventricles are relaxed

20-9

18.2 Heart Valves-AV valves close

• A-V valves close preventing backflow of blood into atria

– occurs when ventricles contract → pushing valve cusps closed

→ chordae tendinae are pulled taut and papillary muscles contract to

pull cords and prevent cusps from everting

20-10

18.6 Heart Valves-AV valves close

•A-V valves close causing LUBB sound

– Occurs during ventricular systole (contraction)

Figure 18.7a The function of the atrioventricular (AV) valves.

© 2016 Pearson Education, Inc.

Direction of

blood flow

Atrium

Ventricle

Cusp of

atrioventricular

valve (open)

Chordae

tendineae

Papillary

muscle

Atria contract, forcingadditional blood into ventricles.

As ventricles fill, AV valveflaps hang limply into ventricles.

Blood returning to theheart fills atria, pressingagainst the AV valves. Theincreased pressure forcesAV valves open.

3

2

1

AV valves open; atrial pressure greater than ventricular pressure

20-12

18.2 Heart Valves-SL valves Open/Close

• SL valves open with ventricular contraction [systole]

– allow blood to flow into pulmonary trunk and aorta

• SL valves close with ventricular relaxation [diastole]

– prevents blood from returning to ventricles

20-13

18.2 Heart Valves-SL valves Open/Close

• SL valves close causing DUBB sound

-occurs during ventricular diastole (relaxation)

Figure 18.8a The function of the semilunar (SL) valves.

© 2016 Pearson Education, Inc.

Semilunar valves open

As ventricles contractand intraventricularpressure rises, bloodis pushed up againstsemilunar valves,forcing them open.

Pulmonarytrunk

Aorta

Figure 18.8b The function of the semilunar (SL) valves.

© 2016 Pearson Education, Inc.

Semilunar valves closed

As ventricles relaxand intraventricularpressure falls, bloodflows back fromarteries, filling thecusps of semilunarvalves and forcingthem to close.

20-16

18.3 Coronary Circulation

REMEMBER- there are 3 types of circulation

Review

-pulmonary

-systemic

-Coronary

20-17

18.3 Coronary Circulation

• Coronary circulation is blood supply to the heart

• Heart is a very active muscle needs lots of O2

• When the heart relaxes high pressure of blood in aorta pushes

blood into coronary vessels

• Many anastomoses

• connections between arteries supplying blood to the same region,

provide alternate routes if one artery becomes occluded (blocked)

20-18

18.3 Coronary Circulation

• Sulci - grooves on surface of heart

containing coronary blood vessels

and fat

• coronary sulcus

• encircles heart and marks the boundary

between the atria and the ventricles

• anterior interventricular sulcus

•marks the boundary between the

ventricles anteriorly

• posterior interventricular sulcus

•marks the boundary between the

ventricles posteriorly

20-19

• Branches off aorta above aortic

semilunar valve

• Left coronary artery

– Anterior interventricular artery

• Blood to septum and anterior walls of ventricles

– circumflex branch

• in coronary sulcus, supplies left atrium and left

ventricle

• Right coronary artery

– marginal branch

• in coronary sulcus, supplies right ventricle

– Posterior interventricular art.

• supplies both ventricles

18.3 Coronary Circulation-Arteries

What would happen if coronary arteries get blocked?Can lead to Angina Pectoris or MI.

Figure 18.10a Coronary circulation.

© 2016 Pearson Education, Inc.

Rightventricle

Aorta

Anastomosis(junction ofvessels)

Superiorvena cava

Left atrium

Pulmonarytrunk

Rightatrium

Rightcoronaryartery

Rightmarginalartery

Posteriorinterventricularartery

Anteriorinterventricularartery

Circumflexartery

Leftventricle

Leftcoronaryartery

20-21

18.3 Coronary Circulation-Veins

• Coronary Sinus- large vessels where veins meet

-dump blood into the Right Atrium

-Seen on posterior side of heart

• 3 veins merge to meet at the coronary sinus

• Great Cardiac vein- in anterior

interventricular sulcus

• Middle cardiac vein- in posterior

interventricular sulcus

• Small cardiac vein- runs along right inferior

margin

• venous blood is collected by cardiac veins →comes from capillary beds in

myocardium

20-22

20-23

REVIEW

1. Which side of the heart acts as a pulmonary pump?

-Right side

2. Which side of the heart acts as the systemic pump?

-left side

20-24

REVIEW

3. Which of the following statements are true?

a. The left ventricle wall is thicker than the right ventricle wall

-True

b. The left ventricle pumps blood at a higher pressure that the right ventricle

-True

c. The left ventricle pumps more blood with each beat than the right ventricle.

Explain.

-False, otherwise blood would back up in either of the circuits

20-25

REVIEW

4. Name the TWO main branches of the Right Coronary Artery.

-Right marginal artery & posterior interventricular artery

5. What is the coronary sinus and what does it do?

-large vessel where cardiac veins meet→ dumps blood into the right atrium