Introduction

Question 1

What are the cranial, dorsal, lateral, ventral and caudal boundaries of the thorax?

Answer 1

Cranially = Thoracic inlet
Dorsally = Thoracic vertebrae
Laterally = Ribcage
Ventraly = Sternum
Caudally = Diaphragm

Question 2

Describe the articulation of the ribs in a dog

Answer 2

Ribs 1-9 join the sternum ventrally
Ribs 10-12 form the costal arch
Rib 13 is floating

Question 3

How many sternebrae does a dog have?

Answer 3

8

Question 4

Name the palpable features on the sternebare

Answer 4

First sternebrae = manubrium

Last sternebrae = xiphoid process that has rings of xiphoid cartilage

Question 5

Describe the divisions of the lungs

Answer 5

Left lung = 2 lobes, cranial and caudal

Right lung = 4 lobes, cranial, middle, caudal and accessory

Question 6

How would you be able to tell apart pigs lungs?

Answer 6

• less obvious divisions between lobes

- surface appears marbled

Question 7

What is the serous membrane lining the thorax?

Answer 7

Pleura

Question 8

How is the pleura sub divided?

Answer 8

Into visceral and parietal

Visceral further divided into: mediastinal, diaphragmatic and costal

Question 9

What is present between the visceral and parietal pleura? What is the purpose of this?

Answer 9

A potential space

- eliminates friction and maintains negative pressure within the pleural space

Question 10

Where does the base of the heart sit compared to the apex?

Answer 10

Dorsally and cranially

Question 11

Name the serous membrane that surrounds the heart

Answer 11

Pericardium

Question 12

What are the 3 layers of the heart, from the inside -> out?

Answer 12

Inner = endocardium
Middle = myocardium
Outer = epicardium

Question 13

What is the name of the additional outpouching on the atria?

Answer 13

Auricle / Atrial appendage

Question 14

The left atrium receives oxygenated blood from the lungs via … ?

Answer 14

The pulmonary veins

Question 15

The right atrium receives deoxygenated blood from the body via … ?

Answer 15

The cranial and caudal vena cavae

Question 16

The left ventricle pumps blood out into … to go to … ?

Answer 16

The aorta, via the aortic valve, to the tissues of the body

Question 17

The right ventricle pumps blood out into … to go to … ?

Answer 17

Into the pulmonary artery, via the pulmonic valve, to the lungs

Question 18

What are the contraction and relaxation phases of the cardiac cycle called?

Answer 18

Contraction = systole
Relaxation = diastole

Question 19

What are the 4 broad phases of the cardiac cycle?

Answer 19

• isovolumetric relaxation
• filling
• isovolumetric contraction
• emptying

Question 20

What do heart sounds S1 and S2 mark?

Answer 20

The start and end of systole

Question 21

If S3 and S4 are audible during diastole, what is this heart rhythm referred to as?

Answer 21

A gallop rhythm

Question 22

What is a murmur?

Answer 22

Any abnormal turbulence within the heart or great vessels that generates a sound

Question 23

Where can you auscultate the heart?

Answer 23

Left side rib space:
- 3 = pulmonic valve
- 4 = aortic
- 5 = mitral
Right side rib space:
- 5 = tricuspid valve

Question 24

Where is the initial electrical impulse in the normal heart generated?

Answer 24

An area of specialised cardiac muscle cells situated in the wall of the right atrium, called the sinoatrial (SA) node.

Question 25

Which node serves as electrical communication between the atria and ventricles?

Answer 25

Atrioventricular (AV) node in the distal interatrial septum

Question 26

Where does the impulse go following the AV node?

Answer 26

Enters the Bundle of His, then divides into 2 branches supplying the ventricular muscle via the Purkinje fibres