Cardiac histology Flashcards

1
Q

What are the receiving chambers of the heart?

A

The two atria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The pumps or discharging chambers are what?

A

Ventricles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What side of the heart pumps blood out to the body? (systemic circuit)

A

The left side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which atrium receives oxygenated blood?

A

The left atrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which side of the heart is for the pulmonary circuit?

A

The right side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which atrium receives deoxygenated blood?

A

The right atrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The heart has a fibrous skeleton- what surrounds the valves and what connects the rings?

A

Four fibrous rings surround the valve orifices

Two fibrous trigones connect the rings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the epicardium?

A

The outer; visceral layer of the serous pericardium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the myocardium?

A

The middle layer, primarily composed of cardiac muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which layer of the heart wall contains the fibrous skeleton of the heart?

A

The mycardium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the endocardium and how many components are in it?

A

It is the inner layer with three components

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the three components of the endocardium and what are they made up of?

A
  1. Endothelial cell layer- inner layer
  2. Subendothelial layer-Underlying layer of dense CT
  3. Subendocardial layer- CT layer
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why are the walls of the left ventricle thicker than those of the right ventricle?

A

Because the left ventricle sends blood to the systemic circuit (the entire body) and has to overcome much more friction than the pulmonary circuit of the right side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Is the heart sitting in a sac?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the purpose of the atrioventricular valves?

A

Prevent backflow into the atria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the two atrioventricular valves?

A

Tricuspid and bicuspid (mitrial) valves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the two semilunar valves?

A

Aortic semilunar and pulmonary semilunar valves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the purpose of the two semilunar valves?

A

To prevent backflow into the ventricles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

T/F both ventricles have the same amount of blood being push out of the ventricles?

A

Truth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Are there valves associated with entrances of venae cavae, coronary sinus, and pulmonary veins into the heart?

A

Nope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

T/F Heart valves enforce one way blood flow through the heart and open/close in response to pressure changes.

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the composition of heart valves?

A

connective tissue overlying endocardium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the three layers of the heart valves?

A

Spongiosa
Fibrosa
Ventricularis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

The tricuspid valve is in on what side of the heart?

A

The right side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

The bicuspid/mitral valve is on which side of the heart?

A

The left!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the spongiosa layer of the heart valve responsible for?

A

Shock absorber

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the fibrosa layer of the heart valve for?

A

It is the core of the valve that contains fibrous extensions from the dense CT of the skeletal rings of the heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the ventricular layer of the heart valve made of and where is it at?

A

Well, it’s dense CT with layers of elastic fibers- adjacent to the ventricular side of the valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Which layer of the heart valve is thickest?

A

The fibrosa layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What allows the cardiac muscle of the heart to depolarize and contract without impulses from the nervous system?

A

The intrinsic cardiac conduction system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Which node is the pacemaker of the heart?

A

The sinoatrial (SA) node

32
Q

An impulse travels from the SA node to the AV node via what?

A

Internodal tracts/pathways

33
Q

How long is the impulse delayed between SA and VA nodes and why?

A

0.1 seconds to allow the atria to contract so the heart doesn’t explode like a balloon as everything contracts at once

34
Q

What is the only electrical connection between the atria and ventricles?

A

The atrioventricular bundle or bundle of His

35
Q

Where are the right and left bundle branches of the atrioventricular bundle headed?

A

toward the apex of the heart through the interventricular septum

36
Q

Where are the purkinje fibers headed?

A

They finish the pathway and head from the apex back up towards the atria

37
Q

Describe the nodal cardiac cells.

A

Found in SA and AV nodes
They are modified cardiac muscle cells
Smaller than surrounding atrial contractile cardiac cells
Contain fewer myofibrils and lack intercalated disks

38
Q

Describe purkinje fibers

A

Found in AV bundle, bundle branches, and subendothelial branches
Also are modified cardiac cells
Larger than surrounding ventricular contractile cardiac cells
Contain myofibrils at periphery of cell
Nuclei are round and larger than nuclei of regular cardiac fibers
Have associated intercalated discs

39
Q

What are the three types of blood vessels?

A

Arteries
Capillaries
Veins

40
Q

What do arteries do?

A

Carry blood away from the heart- oxygenated in systemic circuit, deoxygenated in pulmonary circuit

41
Q

What is the smallest artery called?

A

Arteriole

42
Q

What do capillaries do?

A

smallest of the blood vessels, thin wall- they all the exchange of materials between the blood and body tissues

43
Q

What do veins do?

A

Carry blood towards the heart- oxygen poor blood in systemic circuit and oxygen rich blood in pulmonary circuit

44
Q

What is the smallest vein called?

A

Venule

45
Q

The walls of blood vessels, except the smallest, have three layers. What are they?

A

Tunica intima
Tunica media
Tunica externa

46
Q

Tell me about the tunica externa.

A

In larger vessels this tunic contains a vasa vasorum and a nervi vascularis

47
Q

Tell me about tunica media.

A

Contains rings of smooth muscle cells responsible for vasoconstriction and vasodilation- can contain elastin!

48
Q

Tell me about tunica intima.

A

Has three parts- endothelium, basal lamina, subendothelial layer

49
Q

In cross section ____ will appear more open while _____ will appear more flat.

A

Arteries

Veins

50
Q

What is the thickest layer of arteries?

A

The tunica media

51
Q

What is the thickest layer of veins?

A

Tunica externa

52
Q

What do elastic/conducting arteries do?

A

These are the largest diameter arteries, they are elastic and are important in helping to propel blood onward while ventricles are relaxing- the elastic fibers function as a pressure reserve

53
Q

What are muscular/distributing arteries?

A

Medium sized arteries- contain lots of smooth muscle- regulate blood flow to specific body regions- smooth muscle cells responsible for vasodilation/constriction

54
Q

How big are elastic/conducting and muscular/distributing arteries?

A

Greater than 10mm

2-10 mm

55
Q

Describe small arteries.

A

0.1mm-2mm in diameter and as many as 8 layers of smooth muscle in the tunic amedia

56
Q

Describe arterioles.

A

Smallest artery diameter- 10-100 micrometers- only one or two layers of smooth muscle in the tunica media

57
Q

Describe capillaries.

A

Smallest diameter of blood vessels.
Thin wall
Allows for exchange of materials

58
Q

What are the three types of capillaries?

A

Continuous
Fenestrated
Discontinuous (sinusoidal)

59
Q

Where are continuous capillaries found?

A

In muscles
Lungs
CNS

60
Q

Do continuous capillaries have holes in their walls?

A

No- they have tight junctions

61
Q

Are pinocytotic vessels or pericytes seen in continuous capillaries?

A

Yep

62
Q

Where are fenestrated capillaries found?

A

In endocrine glands and at sites of fluid and metabolite absorption

63
Q

Will you see pinocytotic vessels or pericytes in fenestrated capillaries?

A

Just pinocytotic vessels

64
Q

Where are discontinuous (sinusoidal) capillaries found?

A

Liver, spleen and bone marrow

65
Q

Which capillaries have the biggest holes in them?

A

Sinusoidal capillaries

66
Q

The flow of blood from an arteriole through a capillary network to a postcapillary venule is called what? What is the functional unit called?

A

Microcirculation

Microcirculatory bed/microvascular bed

67
Q

What are the two types of vessels in the capillary network?

A

True capillaries

Ateriorvenous anastomoses/shunts

68
Q

What type of capillary has oval windows? Which type has irregular holes?

A

Fenestrated- ovals

Sinusoidal- irregular

69
Q

If precapillary sphincters relax, more blood flows through which capillaries?

A

True capillaries

70
Q

If precapillary sphincters constrict, where does more blood go?

A

The arteriovenous anastomoses to bypass the true capillaries

71
Q

What are the four types of veins?

A

Venule
Small veins
Medium veins
Large veins

72
Q

Venules receive blood from what?

What are the two types of venules?

A

Capillaries
Postcapillary venule
Muscular venule

73
Q

Small veins receive blood from what?

A

Muscular venules

74
Q

In which veins are all three layers present?

A

Medium and large veins

75
Q

Most veins in the limbs have ___.

A

Valves

76
Q

Valves in veins are really what?

A

Folds in the tunica intima

77
Q

What do valves in veins do? What is their purpose?

A

Prevent backflow