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Flashcards in Cardiovascular System Deck (54)
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1
Q

Cardiovascular system

A

Transport of blood and lymph to and from organs
Consist of the heart, blood vessels, and lymph vessels
Closed system in vertebrates, open in invertebrates

2
Q

Closed system

A

Blood is always maintained within a series of tubes (vessels)
Found in vertebrates

3
Q

Open system

A

Blood (aka hemolymph) leaves the vessels and contacts cells directly
Found in invertebrates

4
Q

Coronary circuit

A

Blood flow through the heart tissue and back to the heart

5
Q

Pulmonary circuit

A

Heart to lungs and back

6
Q

Systemic circuit

A

Everything else besides the coronary and pulmonary circuits

7
Q

Blood flow goes from the _______ –> _______ –> _______ –> _______ –> _______ –> _______ –> _______.

A

heart; arteries; arterioles; capillaries; venues; veins; heart

8
Q

Arterioles and venules comprise the _______.

A

microvasculature

9
Q

Arteries and veins comprise the _______.

A

macrovasculature

10
Q

Portal blood flow

A

Capillary to a vein to a capillary
Hepatic portal system
Hypothalamal hypothoseal portal system

11
Q

Heart

A

4 chambered organ with 4 layers of tissue

Cardiac muscle cells

12
Q

What are the four layers of heart tissue?

A
  1. Epicardium
  2. Pericardium
  3. Myocardium
  4. Endocardium
13
Q

Epicardium

A

Epithelial serous membrane covering the heart

14
Q

Pericardium

A

Membrane that envelops the heart as it grows

2 layers

15
Q

Myocardium

A

Thick, muscular layer of the heart

16
Q

Endocardium

A

3 thin separate layers of the heart

  1. Endothelium
  2. Subendothelial layer
  3. Subendocardial layer
17
Q

Endothelium

A

Layer of the endocardium layer of the heart
Simple squamous epithelium
Makes contact with the blood

18
Q

Subendothelium layer

A

Layer of the endocardium of the heart

Made up of CT fibers such as elastin and collagen

19
Q

Subendocardial layer

A

Layer of the endocardium layer of the heart

Made up of CT fibers such as elastin, collagen, and conducting fibers

20
Q

Purkinje fibers

A

Conducting fibers in the subendocardial layer of the heart
Initiate and transport action potentials
Cluster of large cells; non-contractile, modified muscle cells

21
Q

Pacemakers take over for the _______ when it malfunctions.

A

SA node

22
Q

The heart has a fibrous _______ running throughout the heart muscle that forms the _______.

A

skeleton; valves

23
Q

The two heart valves are the _______ (aka _______ valve) and the _______ valves.

A

bicuspid; mitral; tricuspid

24
Q

The aortic and pulmonary valves are also formed by the _______.

A

fibrous skeleton

25
Q

The heart has _______ innervation.

A

dual

26
Q

The heart is innervated by the _______ and _______ nervous systems, which are both branches of the _______ nervous system.

A

sympathetic; parasympathetic; autonomic

27
Q

Sympathetic innervation of the heart

A

Increases rate and force of contraction
Mediated by norepinephrin
2 sympathetic accelerating nerves
β-1 receptors

28
Q

Parasympathetic innervation of the heart

A

Decreases rate and force of contraction
Mediated by acetylcholine
Vagus nerve (X)
Muscarine receptor

29
Q

Capillaries

A

Tiny numerous bv that are the site of exchange between cells and blood
Made up of simple squamous epithelium (endothelium) anchored to a basement membrane
Have pericytes on top of cells

30
Q

Pericyte

A

Contractile cell with actin, myosin, and tropomyosin that sit on cells of capillaries
Help in healing wounds

31
Q

Continuous capillary

A

Has zona occludens for tight junctions and inhibition of paracellular movement
Forms the BBB

32
Q

Fenestrated capillary

A

Has fenestrations in the cell membrane with a very thin diaphragm (thinner than the cell membrane)
Found in places where you need quick exchange, such as the kidneys, endocrine cells, and the intestine

33
Q

Sinusoidal capillaries

A

Have large spaces between cells with no basal lamina covering the spaces, only covering the individual cells
Allows RBC exchange
Found in the spleen and bone marrow

34
Q

Blood vessels have 3 layers, or _______, called _______, _______, and _______.

A

tunics; tunica intima; tunica media; tunica adventitia

35
Q

Tunica intima

A

Innermost tunic of a blood vessel
Simple squamous epithelium (endothelium)
Has a sub endothelial layer that anchors and separates this tunica from the next tunic

36
Q

Tunica media

A

Middle tunic of a blood vessel

Smooth muscle that recoils and stretches

37
Q

Tunica adventitia

A

Outermost tunic of a blood vessel
Fibrous CT surrounding the entire tube
Continuous with surrounding tissue

38
Q

Internal elastic membrane

A

Condensation of elastic fibers found between the tunica intima and tunica media
Found mainly in arteries; small amounts may be found in other bv

39
Q

External elastic membrane

A

Condensation of elastic fibers found between the tunica media and tunica adventitia
Only found in large arteries

40
Q

Vasa vasorum

A

“bv of the bv”
Blood supply for very large vessels, such as the aorta and the vena cavas
Bv is so thick in these vessels that it needs its own supply of blood, nutrients, and waste elimination
Found in the tunica media of these vessels

41
Q

What regulates the diameter of bv?

A

Nerve fibers

42
Q

Sympathetic nerve innervation of bv

A

Release of norepinephrine makes the bv contract, making the lumen smaller (less blood flow)
Important in arterioles, the main vessels for blood flow regulation

43
Q

Sympathetic nerve fibers terminate in the _______ and release _______, where it must diffuse through the tunics to get to receptors on _______ muscle.

A

tunica adventitia; norepinephrine; smooth

44
Q

Relaxation of bv can be _______ or _______.

A

passive; active

45
Q

Passive relaxation of bv is due to _______.

A

lack of norepinephrine when there is no sympathetic innervation

46
Q

Active relaxation of bv is due to _______.

A

acetylcholine release of parasympathetic innervation

47
Q

Parasympathetic active relaxation of bv

A

ACh released –> Nitric oxide production –> diffuses to sm. muscle –> activates guanylyl cyclase –> forms cyclic GMP –> activates kinase G –> SERCA –> no contraction (larger lumen, therefore more blood flow)

48
Q

SERCA

A

Ca+ pump on SER

Pumps Ca+ into SER out of muscle cytoplasm

49
Q

Nitric oxide

A

NO
Toxic
Cells use to communicate

50
Q

Artery

A

Very thick tunica media

No valves except for semilunar valves of pulmonary artery and aorta

51
Q

Vein

A

Very thick adventitia

Large veins have modified tunica intima that forms valves

52
Q

Valve

A

Specialization of tunica intima that prevents back flow of blood
Found in veins, pulmonary artery, aorta

53
Q

Varicose vein

A

Swollen, discolored vein close to skin surface

Can develop phlebitis, which can lead to clots that can become a thrombus and clog vessels

54
Q

Phebitis

A

Inflammation of a vein