Histology of heart/vessels

Question 1

What part holds the most blood from most to littlest

Answer 1

Peripheral veins 65%
Heart and Lungs 20%
Peripheral arteries 10%
Capillaries 5%

Question 2

What are the 3 basic layers of the blood vessels

Answer 2

Inner layer: Tunica intima
Middle layer: Tunica media
Outer layer: Tunica adventitia

Question 3

What is the Tunica intimacy made of

Answer 3

Single layer of squamous epithelial cells called endothelial cells supported by the basal lamina and a thin layer of connective tissue

Question 4

What is the Tunica media made up of

Answer 4

Predominantly of smooth muscle

Question 5

What is the Tunica adventitia made up of

Answer 5

Supporting connective tissue

Question 6

What separates the tunica intimacy from the tunica media

Answer 6

layer of elastic tissue called the internal elastic membrane

Question 7

What separates the tunica media and adventitia

Answer 7

layer of elastic tissue called the external elastic membrane

Question 8

What are elastic arteries

Answer 8

Largest arteries like the aorta
They have many sheets of elastic fibres in the tunica media

Question 9

What is the Vasa vasorum

Answer 9

The own vascular supply of large vessels

Question 10

What are Arterioles and what are they mad of

Answer 10

Small arteries
Have tunica intimacy, only 1 or 2 layers of smooth muscle in the tunica media and almost no adventitia

Question 11

What are meta arterioles

Answer 11

Smooth muscle are replaced by dis-continuous non-contractile cells called pericytes
terminated into capillaries

Question 12

What are capillaries composed of

Answer 12

Endothelial cells and basal lamina
Often have pericytes which have contractile properties

Question 13

What are continuous capillaries and where are they found

Answer 13

No gap between endothelium
muscle, connective tissue, lung, skin and nerve

Question 14

What are Fenestrated capillaries and where are they found

Answer 14

Small gaps in endothelium but basal lamina is continuous
mucosa of gut, endocrine glands, glomeruli of kidney

Question 15

What are Sinusoidal/Discontinues capillaries and where are they found

Answer 15

Large gaps in the endothelium and no basal lamina
Liver, spleen and bone marrow

Question 16

What are post-capillary venules

Answer 16

Where capillaries drain into
Which are endothelial cell-lined and contain thin layer of connective tissue

Question 17

What is the difference between a Vein and an artery

Answer 17

Thin tunica media
Thick tunica adventitia containing bundles of longitudinally orientated smooth muscle
Valves which are extension from the tunica intima

Question 18

What are the 3 layers of the heart

Answer 18

Endocardium (inner layer)
Myocardium (middle layer)
Epicardium (outer layer)

Question 19

What is the Endocardium made of

Answer 19

Endothelium
Basal lamina
Thin layer of collagen fibres
Layer of denser connective tissue
Some areas subendocardium

Question 20

What is a subendocardium

Answer 20

loose connective tissue containing small blood vessels and nerves and branches of impulse conducting system

Question 21

What is the structure of the Myocardium

Answer 21

Bundles and layers of contractile cardiac muscle fibres
Individual muscle fibres are surrounded by connective tissue with capillaries

Question 22

What is the structure of the Epicardium

Answer 22

Surface: single layer of flattened epithelium called mesothelium
Basal lamina
Fibroelastic connective tissue and some places adipose tissue

Question 23

What are the 2 parts of the pericardium

Answer 23

Fibrous pericardium (connective tissue)
Serous pericardium

Question 24

What is the pericardium made up of

Answer 24

Layer of simple squamous epithelium (mesothelium) backed by basal lamina and connective tissue

Question 25

What are the parts of the Serous pericardium called

Answer 25

Parietal Serous pericardium touching the fibrous pericardium
Visceral serous pericardium touching the heart

Question 26

What separates the fibrous and serous pericardium

Answer 26

Pericardial cavity

Question 27

What is the Fibrous skeleton of the heart

Answer 27

Formed by thick bands of fibrous connective tissue

Question 28

What are heart valves made of

Answer 28

Outer endothelial layer with basal lamina
Layer of collagen and elastin fibres
Core connective tissue called lamina fibrosa
No blood vessels

Question 29

What are the 3 types of cardiac muscle cells

Answer 29

Contractile cells 99%
Pacemaker cells
Conducting cells

Question 30

Do lymphatic vessels have a central pump

Answer 30

No but smooth muscle in walls, pressure in tissue and compression of vessels combined with valves in vessels produce flow