Lecture 6 DA

Question 1

Why are dense breasts an issue in mammograms?

Answer 1

Tumours are harder to visualise by mammogram in dense breasts.

Question 2

What is the effect of breast cancer on suspensory ligaments, and what is a consequence of this?

Answer 2

They are damaged by cancerous growth. This can cause dimpled skin and can invert the nipple.

Question 3

Describe the pathway a metastasizing cell will take once it enters the lymphatic system.

Answer 3

It enters through many lymph nodes before it reaches the veinous system. Can metastasize at these lymph nodes.

Question 4

What can be said about breast tissue in males?

Answer 4

Males still have a minimal amount of breast tissue, mammary glands, however they don’t ever fully develop (normally). With hormonal influence, they can.

Question 5

Why can males get breast cancer?

Answer 5

They have a small amount of mammary glands and low duct development, however, this allows for possible tumour growth.

Question 6

What is found between two ventricles and between an atrium and ventricle?

Answer 6

Between two ventricles is the interventricular groove.
Between an atrium and a ventricle is the atrioventricular groove.
Anterior and posterior grooves for both.

Question 7

What structure of the heart is dominantly seen in situ?

Answer 7

Right atrium.

Question 8

Is the apex of the heart anterior or posterior?

Answer 8

Posterior.

Question 9

What does the superior vena cava ultimately drain?

Answer 9

Everything above the diaphragm.

Question 10

After the inferior vena cava pierces the central tendon, does it have any branches? Why is this so?

Answer 10

It has no branches superior to the central tendon. This is because it only drains below the diaphragm, and the superior vena cava is responsible for above the diaphragm.

Question 11

What is the name of the rough muscular wall in the interior of the atria?

Answer 11

Musculi pectinati.

Question 12

What borders the musculi pectinati? What is its appearance?

Answer 12

Crista terminalis. It has a smooth appearance, unlike the rough musculi pectinati.

Question 13

What is found directly exterior to the crista terminalis? Why is this important clinically?

Answer 13

The sulcus terminalis. It is clinically important, as it is probably the only landmark for the sinoatrial node.

Question 14

What is the foramen ovali, and what is its purpose? What does it become in adults? What does its repair resemble?

Answer 14

It is a foramen found in foetal (yes, foetal, not fetal. I know foetal doesn’t have as much freedom, but hold the urge) development. It allows blood to bypass the pulmonary circulation so as not to waste energy.
It becomes the fossa ovalis in adults. When it closes, it resembles a wound repair.

Question 15

What is the coronary sinus, and where is it found?

Answer 15

It is what drains the heart of its deoxygenated blood, and is direct. It is found within the right atrium, between the fossa ovalis and atrioventricular orifice.

Question 16

What is the auricle, and where is it found?

Answer 16

It is a remnant of heart tissue, found at the base of the pulmonary trunk. It is a consequence of heart development.

Question 17

What is the main driver of moving blood from the atria to the ventricles?

Answer 17

Only 10% of blood movement is due to atrial contraction. The rest is due to suction created by the ventricle expanding.

Question 18

What are chordae tenidae, and how many are on each side of the heart?

Answer 18

They are fine, string-like tendons that anchor the valves of the atrioventricular orifice. There are three for the tricuspid (right), and two for the bicuspid/mitral (left).

Question 19

What are papillary muscles?

Answer 19

Finger-like muscles projecting off the muscle wall, to which chordae tendinae anchor to.

Question 20

What is the trabeculae carnae?

Answer 20

The rough muscle found within the interior of ventricles (the same as musculi pectinati of atria, different name).

Question 21

What is the septomarginal band, and what is its significance?

Answer 21

It connects the anterior papillary muscles with the medial wall of the heart, allowing the contraction signal to conduct through, allowing a synchronised heart-beat.

Question 22

What valve is found prior to pulmonary trunk, and how is it different from the tricuspid/mitral/bicuspid?

Answer 22

It is the pulmonary semilunar valve, and unlike the atrioventricular valves, it has no chordae tendinae.

Question 23

What side does the heart sit on?

Answer 23

The heart sits on the left atrium.

Question 24

How many pulmonary veins are there?

Answer 24

Four total, two left, and two right.

Question 25

What is the right atrioventricular valve called?

Answer 25

Tricuspid valve.

Question 26

What is the left atrioventricular valve called?

Answer 26

Bicuspid valve, also called mitral valve.

Question 27

What valve precedes the aorta?

Answer 27

Aortic semilunar valve.

Question 28

Describe the foetal (bald eagle screech) circulation.

Answer 28

Blood bypasses the pulmonary circulation. Oxygen instead comes from the pacenta via the liver. Foramen ovali bypasses the pulmonary circulation, as does ductus arteriosis, which is found above the pulmonary trunk, which communicates with the aorta for further bypass.

Question 29

What is the aortic vestibule?

Answer 29

A swelling found at the base of the aorta (interior).

Question 30

What happens to the foetal (sounds like this word needs some freedom aye?) circulation after birth?

Answer 30

Atmospheric pressure causes expansion of the lungs, which means airflow within. This increases the pressure in the left atrium which closes the foramen ovali. It also means the release of hormones which close the ductus arteriosis.

Question 31

What is the purpose of the heart’s fibrous skeleton?

Answer 31

It is composed of connective tissue, and seperates the artia and ventricles, to allow for synchronised heart beats.
It forms a figure 8 around the atrioventricular valves, which are found on the same plane.