Structures of Blood vessels and Heart

Question 1

Order of blood vessels the blood passes through after the heart

Answer 1

Heart
Elastic arteries 
Muscular arteries
Arterioles
Capillaries
Venules
VEins
Muscular veins

Question 2

What is the innermost layer of the blood vessels

Answer 2

Tunica intima

Question 3

What is the middle layer of the blood vessels

Answer 3

Tunica media

Question 4

What is the outermost layer of the blood vessels

Answer 4

Tunica adventitia

Question 5

What does the tunica intima have lining the lumen

What does it have adjacent to this

Answer 5

Simple squamous epithelium lining the lumen

AN adjacent layer of connective tissue

Question 6

What is the tunica media made of

Answer 6

• Smooth (or cardiac) muscle which is mainly circular

- Varying amounts of elastin, mainly in sheets in the interspersed connective tissue

Question 7

What does the tunica adventitia consist of

Answer 7

-connective tissue with varying amounts of interspersed elastic fibres and smooth muscle cells (mainly longitudinal)

Question 8

What layers does the heart have

Answer 8

Endocardium (tunica intima)
Myocardium (tunica media)
Epicardium (tunica adventitia)

Question 9

What is the difference between the tunica media in the heart vs vessels

Answer 9

In the tunica media, it consist of cardiac and not smooth muscle

Question 10

What is the squamous epithelium in the endocardium lined by

Answer 10

Thin band of relatively loose connective tissue

Question 11

What is the myocardium supplied by

Answer 11

Coronary vessels

Question 12

What is the epicardium like

Answer 12

Partially dense, partially loose connective tissue

Question 13

What is the connective tissue in the epicardium bordered with

Answer 13

Simple squamous epithelium (visceral pericardium) which forms the inner lining of the pericardial sac

Question 14

What is pulsating blood flow met by In elastic arteries

Answer 14

Lamellae of elastin woven into the media

Question 15

What do muscular arteries do

Answer 15

Help distribute the bulk of blood to the site of need eg to the leg muscles when cycling

Question 16

Using a histological stain and looking at the tunica media, what does collagen look like

Answer 16

Red with few thin interspersed elastin sheets

Question 17

USing a histological stain and looking at the tunica media, what do the circular smooth muscle cells look like

Answer 17

Brown

Question 18

Using a histological stain, what does the external elastic membrane look like in the tunica media

Answer 18

Black

Question 19

What is a blood vessel with a perpendicular pattern most likely to be

Answer 19

Artery or arteriole

Question 20

Which vessels are the main site of blood pressure regulation

Answer 20

Arterioles

Question 21

How many smooth muscle cells would an arteriole have

Answer 21

1-3

Question 22

Why are there no internal elastic membranes in small arteries and arterioles

Answer 22

Because flow is not pulsating anymore

Question 23

Why do small arteries and arterioles not have vasa vasorum

Answer 23

Because their walls are small enough to be supplied by diffusion

Question 24

What do capillaries not have

Answer 24

Media or adventitia

Question 25

What do capillaries contain

Answer 25

One layer of endothelial cells

A few collagen fibres around it

Question 26

How are larger molecules transported through capillary walls

Answer 26

IN small vesicles by pinocytosis

Question 27

Difference between continuous capillaries and fenestrated capillaries

Answer 27

-Continuous= Lumen is lined by a continuous uninterrupted layer of single endothelial cells that are linked by cell-cell contacts containing tight and adherent junctions

Fenestrated= numerous pores in their endothelial cells. Therefore the barrier to the interstitial is the basement membrane

Question 28

Where are sinusoids found

Answer 28

Liver and the spleen

Question 29

What are sinusoids

Answer 29

Beds of wide capillaries with diameters of several erythrocytes. Their endothelial cells and basement membranes have holes which allow plasma to directly reach cells. This allows fast exchange of larger components

Question 30

What are pericytes

Answer 30

cells that wrap around endothelial cells throughout the body. They are essential for the regulation of blood flow and maintenance of homeostasis within the body, such as the blood-brain barrier.

Question 31

What do venules not have

Answer 31

No media and no or hardly any adventitia

Question 32

In the extremities, what are muscular arteries often accompanied by and what does this do (vein-artery-vein triplets)

Answer 32

Accompanied by veins on either side so that the pulsations slightly compress the veins, driving the blood towards the heart due to the valves

Question 33

What does the portal vein do

Answer 33

Links the capillary beds of the digestive system and spleen directly to the capillary bed (sinusoids) of the liver

Question 34

What is an anastomosis

Answer 34

Direct link between an artery or vein without a capillary bed in between

Question 35

How does fluid enter the lymphatic system

Answer 35

Blood circulation is slightly leaky and so fluid leaves mainly in the capillary beds.

Question 36

Why does fluid leave the capillary beds

Answer 36

Because of blood pressure and osmotic differences between blood and interstitial fluid

Question 37

Pathway of fluid before it goes into lymphatic vessels and back into the blood circulation

Answer 37

Fluid leaks out, and drains from the tissues as lymph via lymph vessels which feed as afferent lymphatics into lymph nodes. Lymph is checked for antigens in lymph nodes. After checks, the lymph enters the lymphatic ducts, which empty into the subclavian veins.