Circulatory system

Question 1

Where is the mediastinum

Answer 1

space bounded anteriorly by sternum and costal cartilage

Question 2

What are the divisions of the mediastinum

Answer 2

1. superior mediastinum
2. inferior mediastinum
   a. anterior mediastinum
   b. middle mediastinum
   c. posterior mediatinum

Question 3

What is present in the superior mediastinum

Answer 3

• arch of aorta
• brachiocephalic trunk
• left subclavian branch
• right and left brachiocephalic veins
• inferior part of the superior vena cava
• right and left phrenic nerves
• right and left vagus nerve
• trachea
• esophagus
• thymus gland
• thoracic duct

Question 4

What are the major branches of the superior mediastinum

Answer 4

• arch of aorta
• brachiocephalic trunk
• left subclavian vein

Question 5

What is in the brachiocephalic trunk

Answer 5

we have 2 brachiocephalic veins but there is only 1 brachiocephalic artery

Question 6

Where is the esophagus located in the mediatinum

Answer 6

posterior and superior mediatinum

Question 7

What is present in the posterior mediatinum

Answer 7

-descending aorta, right and left vagus nerve, thoracic duct, esophagus, sphlanchnic nerves

Question 8

What is present in the middle mediastinum

Answer 8

heart, pericardium, right and left phrenic nerves

Question 9

What is present in the anterior mediastinum

Answer 9

thymus

Question 10

Describe the orientation of the heart

Answer 10

base of the heart faces posteriorly and the apex points anteriorly and slightly towards the left

Question 11

What are the surfaces of the heart

Answer 11

1. anterior surface= sternocostal surface
2. inferior surface =diaphragmatic surface, it leans on the diaphragm
3. left and right surface= pulmonary surface
4. posterior surface= base of heart

Question 12

What are the 2 major grooves of the heart

Answer 12

A. interventricular sulcus
1. anterior interventricular sulcus
2. posterior interventricular sulcus
B. coronary sulcus

Question 13

Where are these structures located

a. anterior interventricular sulcus
b. posterior interventricular sulcus

Answer 13

a. anterior surface/sternocostal surface

b. inferior/diaphragmatic surface

Question 14

Interventricular sulcus

Answer 14

separates the ventricles

Question 15

What is the auricle , where do you find it

Answer 15

small sac on top of the atrium

Question 16

What is the coronary sulcus

Answer 16

it encircle the heart and separate the atria from the ventricles

Question 17

What is the shallow fossa that separates the left and right atrium

Answer 17

fossa ovalis

Question 18

What is the muscles in the ventricles

Answer 18

trabeculae carnea ( does not produce hormones unlike those muscles of the atria - pectinate muscles)

Question 19

contraction of atria is equal to?

Answer 19

auricles are only part of the atria that have muscle tissue

Question 20

What are papillary muscles

Answer 20

subdivision of trabeculae carnea, attach to walls of ventricles and the other attaches to the chorda tendinae

Question 21

What is the function of papillary muscles

Answer 21

1. keep the atrioventricular valve closed during ventricular systole ( prevent it from inverting to atria).

Question 22

How many layers cover the heart

Answer 22

Almost 3 layers

Question 23

What covers the heart

Answer 23

pericardial sac that contains the fibrous pericardium and inner serous layer

Question 24

What is a serous membrane

Answer 24

CT that secretes serous fluid that helps lubricate organs

Question 25

What is the function of the fibrous pericardium

Answer 25

mechanical protection and surrounds the heart and attaches to the central tendon and diaphragm

Question 26

What are the layers of the serous pericardium?

Answer 26

• parietal layer: lines the inner surface of the fibrous pericardium
• visceral layer/epicardium: attaches to surface of heart

Question 27

What is cardiac tampanade

Answer 27

serious buildup of serous fluid in the pericardial cavity that causes increased pressure along the pericardium.