dccc the heart & ekg #4 cardiovascular i the...

Bio 151 – Laboratory Manual Human Anatomy & Physiology II DCCC The Heart & EKG

Last updated 06/20/2012

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#4 Cardiovascular I – The Heart

Objectives:

Identify a list of human heart structures using a virtual human dissection

Dissect a sheep heart to identify external and internal structures

Identify a list of human heart structures on a model

Equipment: Remember to bring gloves, goggles,

appropriate shoes, photographic atlas.

I. Introduction

The heart has four chambers – two upper atria

(singular, atrium) and two lower ventricles.

Blood enters the atria from the large veins and

passes into the ventricles before being ejected

from the heart within the large arteries to either

the lungs or the rest of the body (Fig. 1).

II. Virtual Human Heart Examination

Preparation

1. Start the Anatomy & Physiology

Revealed® software by double clicking the icon.

2. On the home screen, from Module (top center)

select Cardiovascular from the drop down Menu.

3. From the icon list at the top center, click the left

most icon (the dissection icon).

4. Under the Structure List column (top left) use

the Topic drop down menu to choose Thorax.

5. From the View drop down menu choose

Arteries-anterior. Do not select a Structure Type

at this point.

6. At the bottom of the left column are the layer

tools. Move the red arrows down to gradually

remove each layer of the body. The layers must be

removed in order. Remove Layers 1 and 2 to

visualize the pericardium in Layer 3.

Figure 1. Structures of the human heart

Bio 151 – Laboratory Manual Human Anatomy & Physiology II DCCC The Heart & EKG

Last updated 06/20/2012

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7. To identify visible structures within a

layer, click on the radio button at the top

of the layer that is on display. Pins will

appear marking labeled structures.

8. Hover over a pin and the name of the structure

will appear. Or click on a pin and the structure will

be highlighted in the main view and further

information on the structure will appear in the

various boxes in the left column. Another

identification method is to click on the name of the structure in the information section.

9. Practice using the layer tools and highlighting structures by clicking on the pin or structure

name.

III. Virtual Human Heart Examination

Cardiovascular system, thorax, arteries-anterior, dissection layer 3

Structures AP Revealed®

1. pericardium (also

known as pericardial sac)

1. The introductory instructions

on page 2 will bring you to

this view (APR Fig. 1).

2. Note the position of the heart

within the thoracic cavity.

3. The heart is enclosed in the

double-layered pericardium

(APR Fig. 1).

APR Fig.1

Cardiovascular system, thorax, arteries-anterior, dissection layer 4

Structures AP Revealed®

2. heart

3. aorta

a. aortic arch

b. brachiocephalic

artery

c. left common carotid

artery

d. left subclavian

artery

4. pulmonary trunk

5. vena cava

a. superior

b. inferior (not shown)

1. Use the layer tool to move one

layer deeper (Layer 4). The

pericardium is removed in

this layer revealing the major

vessels associated with the

heart (APR Fig. 2).

2. Use the labeling pins to locate

the aorta (3), superior vena

cava (5a), and pulmonary

trunk (4).

3. Note: the vessels branching

from the aorta are labeled in

APR Fig 3.

APR Fig. 2

1

3

5a

2

4

Bio 151 – Laboratory Manual Human Anatomy & Physiology II DCCC The Heart & EKG

Last updated 06/20/2012

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Cardiovascular system, thorax, arteries-anterior, dissection layer 5

Structures AP Revealed®

3. aorta

a. aortic arch

b. brachiocephalic

artery

c. left common carotid

artery

d. left subclavian

artery

1. Use the layer tool to move to

Layer 5 (APR Fig. 3).

2. The anterior veins have been

removed to reveal the arteries

branching from the aortic

arch.

3. Locate the aorta arch (3a),

brachiocephalic (3b), left

common carotid (3c), and left

subclavian (3d) a.

APR Fig. 3

Cardiovascular system, heart, vasculature-anterior, dissection layer 2

Structures AP Revealed®

6. coronary arteries

a. right

b. left

7. pulmonary arteries (not shown in this view)

8. right and left

pulmonary veins (right

shown in this view)

1. To see the heart details,

choose Heart from the Topic

drop down menu in the left

column. Choose Vasculature-

anterior under the View menu.

Move to Layer 2 (APR Fig. 4).

2. Use the labeling pins for all

three layers to locate the

structures on the left.

Also shown in this view are the

cut end of the superior and

inferior vena cavae (5a,b).

APR Fig. 4

Cardiovascular system, heart, internal features-anterior, dissection layer 1

Structures AP Revealed®

9. auricle

a. right

b. left

10. ventricle

a. right

b. left

11. apex

1. Choose Heart from the Topic

menu and Internal features-

anterior from the View menu

(APR Fig. 5).

2. Use the labeling pins to locate

the structures on the left

APR Fig.5

9a

9b

10a

10b

11

3c 3b 3d

3a

5b

6a

5a

6b 8

Bio 151 – Laboratory Manual Human Anatomy & Physiology II DCCC The Heart & EKG

Last updated 06/20/2012

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Cardiovascular system, heart, internal features-anterior, dissection layer 5

Structures AP Revealed®

12. atrium (atria, pl.)

a. right

b. left

13. interventricular

septum

14. atrioventricular

valve

a. right (tricuspid)

b. left (bicuspid)

15. papillary muscle

16. chordae tendineae

17. semilunar valve

a. pulmonary (not

visible in this figure)

b. aortic

1. Move to Layer 5 (APR Fig. 6).

2. In this view, move up and

down through Layers 2-6 to find

the appropriate labeling pins for

the structures on the left.

APR Fig. 6

III. Sheep Heart Dissection

A. Preparation

1. Wear goggles, gloves, and an apron for the entire time that you are working with

preserved specimens.

2. Obtain a dissecting tray and a sheep heart.

B. Exterior Observations

auricles (right and left)

ventricles (right and left)

apex

pulmonary trunk

aorta

Use your atlas to orient the heart. The prominent features on the anterior surface are the left

auricle and the pulmonary trunk. Most of the vessels will emerge on the posterior surface,

however, they might have been cut close to the heart and only the openings will be visible. The

apex is composed of the left ventricle.

C. Interior Observations

atria (right and left)

ventricles (right and left)

interventricular septum

atrioventricular valves

tricuspid (right)

bicuspid/mitral (left)

semilunar valves

aortic

pulmonary

chordae tendineae

papillary muscle

12a

16

13

12b

14a

17b

14b

15

Bio 151 – Laboratory Manual Human Anatomy & Physiology II DCCC The Heart & EKG

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Make a frontal section with your scalpel by cutting through the center of the left auricle toward

the apex. Continue the cut around the apex and up through the right auricle. Note that the heart is

asymmetrical. The left ventricle makes up apex, is the largest chamber of the heart with the

thickest wall. The interventricular septum separates the two ventricles. The right ventricle is

slightly posterior to the left ventricle and much smaller. Locate the atrioventricular valves

between the atria and ventricles. The chordae tendineae are attached to the inferior aspect of the

valves. Papillary muscles bind the chordae tendineae to the ventricle walls. The aortic and

pulmonary semilunar valves are at the junction of the atria with the aorta and pulmonary trunk,

respectively. Confirm the location of each vessel by inserting a blunt probe through the atria.

D. Directions for Cleaning Up

1. All specimen tissue should be thrown away in the red biohazard containers. Please do

NOT allow tissue to end up in the sink. They will clog the drain and cause extra work for

lab assistants.

2. Thoroughly wash your dissecting tray with soap and water, dry, and return it to the lab

bench where you found it.

3. Use the spray disinfectant cleaner provided to thoroughly wipe down your lab bench

area so that it will be ready for the next group of students.

4. Dispose of your gloves, paper towels and old plastic bags in the regular trash

containers, NOT the red biohazard containers.

5. Make sure that you take your dissecting kit and goggles with you when you leave the lab.

IV. Heart Model Observation

Locate the following structures on the human heart model:

aorta

─ brachiocephalic artery

─ left common carotid artery

─ left subclavian artery

pulmonary trunk

vena cava

─ superior

─ inferior

auricle

─ right

─ left

ventricle

─ right

─ left

apex

pulmonary arteries

pulmonary veins

atria

─ right

─ left

interventricular septum

atrioventricular valve

─ right (tricuspid)

─ left (bicuspid or mitral)

papillary muscle

chordae tendineae

semilunar valve

─ pulmonary

─ aortic

Bio 151 – Laboratory Manual Human Anatomy & Physiology II DCCC Cardiovascular I – The Heart Name:_________________________

Last updated 06/20/2012

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Laboratory Report

For each label in the human heart figure above, give the name of the structure on the correct line

below.

A. _____________________________

B. _____________________________

C. _____________________________

D. _____________________________

E. _____________________________

F. _____________________________

G. _____________________________

H. _____________________________

I. _____________________________

J. _____________________________

K. _____________________________

L. _____________________________

M. _____________________________

N. _____________________________

O. _____________________________

P. _____________________________