Lecture 8

Question 1

Name the branching arteries off the aorta

Answer 1

Right brachiocephalic, left carotid, left subclavian,

Question 2

what does the right brachiocephalic break up into

Answer 2

right common carotid artery and right subclavian artery

Question 3

what part of the heart lies on the diaphragm?

Answer 3

the right ventricle lies flat

Question 4

what lies in the atrioventricular groove?

Answer 4

right coronary artery and vein and also the tricuspid valve.

Question 5

where does the coronary arteries originate

Answer 5

behind the two cusps of the aortic valve

Question 6

what runs in the atrioventricular groove

Answer 6

right coronary artery

Question 7

Where does the left coronary artery run and what does it give rise to?

Answer 7

In the interventricular groove, the anterior interventricular artery.

Question 8

what lies within the atrioventricular groove?

Answer 8

coronary sulcus

Question 9

what is the first branch of the right coronary artery

Answer 9

the sinoatrio node

Question 10

what is the main coronary vein that drains back into the right atrium

Answer 10

coronary sinus

Question 11

great cardiac vein? Where? empty into?

Answer 11

anterior interventricular sulcus, coronary sinus

Question 12

middle cardiac vein? where? drains into? what is with it?

Answer 12

posterior interventricular sulcus, coronary sinus, posterior interventricular artery.

Question 13

what does each lobe of the lung divide into

Answer 13

bronchopulmonary segments

Question 14

what proportion of the lung is capillaries

Answer 14

70%

Question 15

Which shunt then ensures that most blood (oxygenated ) is passed to the systemic circulation

Answer 15

ductus arteriosis

Question 16

two portions of the atria?

Answer 16

atria has a smooth wall portion,

and a muscular portion

Question 17

what are the 3 types of cardiac muscle?

Answer 17

myocardium: specialised muscle cells make up the muscular layer of the heart wall.
Endocardium: interior surface of the heart chambers, (also covers the heart valves. One way passages that allow blood to flow between chambers of the heart.
Pericardium: think double layered sac that surrounds the heart

Question 18

name the path of the impulses within the heart

Answer 18

SA node, gather at the AV node, passes through a thick bundle of fibres (atrioventricular bundle), spreads through the interventricular septum with 2 branches (Purkinje fibre branches, one left, one right), you get a large elongated cardiac muscle (fewer microfibres, located right under the endothelial lining of the cavity.

Question 19

What causes the ventricles to contract at the same time

Answer 19

Purkinje fibre branches, one left, one right

Question 20

what is the forament ovalis composed of prenatally

Answer 20

two septa

Question 21

what overall changes must occur during birth

Answer 21

change from single to double circulatory system

Question 22

Describe the changes to the heart, mentioning the lungs and placenta, after birth

Answer 22

the lungs are filled with ameotic fluid
(no air). After birth, first breath, umbilical cord is cut, the fetal blood remains in the placenta (less blood going to the umbilical veins), and to the right atrium in general. Blood pressure in the right and left atria differs (less in RA), The reverse in pressure ensure that the foremen ovalis’s valve is closed by the pressure of the LA. When the child takes the first breath, the capillaries in the lungs expand, blood flows through the lung system (extensive),, lots of blood goes in (oxygenation from air (lots of SA)). LA gets more blood

Question 23

what duct goes from the umbilical vein to the IVC

Answer 23

The ductus venosus through the liver

Question 24

WHAT DOES PHERIPHERAL MEAN

Answer 24

oN THE eDGE OF SOMETHIN

Question 25

what keeps the ductus arteriosus open?

Answer 25

Smooth muscle and prostaglandins(inhibits smooth muscle contraction) (keeping it open is very important)

Question 26

what happens if the ductus arteriosus doesn’t close

Answer 26

if it doesn’t close, aortic pressure is too great. Blood in the lungs, increase pressure, and problems, respiratory problems.

Question 27

what happens if the foramen ovalis doesn’t close

Answer 27

child cyanotic.
if the valve doesn’t close it properly, there will be blood coming from the venous side to the left side (oxygenated), disturbing the rest of the body from getting oxygen.

Question 28

how does the ductus arteriosus close?

Answer 28

reflex closure, involving enzymes (within minutes 
Contraction. 
Smooth muscle degenerate
Whole structure becomes fibrous
And ductus arteriosus
(takes a few weeks)

Question 29

when does the ductus arteriosus doesn’t close (more likely)

Answer 29

premature births (high frequency of ductus arteriosus being open at birth) 
4X normal

Question 30

R/L Liver

Answer 30

Right

Question 31

R/L Spleen

Answer 31

left

Question 32

R/L Heart

Answer 32

left

Question 33

R/L Appendix

Answer 33

right

Question 34

R/L Stomach

Answer 34

left

Question 35

what is the term used to describe the mirror image of the normal development of organs

Answer 35

situs inversus (begins at a molecular level, early in development) (opposing situs solitus)

Question 36

what two major events drive functional adaptations to the circulatory system at birth

Answer 36

cutting the umbilical cord, changes to lungs after the first breath