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Flashcards in Cardiovascular System Deck (54):
1

Cardiovascular system

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

Closed system

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

3

Open system

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

4

Coronary circuit

Blood flow through the heart tissue and back to the heart

5

Pulmonary circuit

Heart to lungs and back

6

Systemic circuit

Everything else besides the coronary and pulmonary circuits

7

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

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

8

Arterioles and venules comprise the _______.

microvasculature

9

Arteries and veins comprise the _______.

macrovasculature

10

Portal blood flow

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

11

Heart

4 chambered organ with 4 layers of tissue
Cardiac muscle cells

12

What are the four layers of heart tissue?

1. Epicardium
2. Pericardium
3. Myocardium
4. Endocardium

13

Epicardium

Epithelial serous membrane covering the heart

14

Pericardium

Membrane that envelops the heart as it grows
2 layers

15

Myocardium

Thick, muscular layer of the heart

16

Endocardium

3 thin separate layers of the heart
1. Endothelium
2. Subendothelial layer
3. Subendocardial layer

17

Endothelium

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

18

Subendothelium layer

Layer of the endocardium of the heart
Made up of CT fibers such as elastin and collagen

19

Subendocardial layer

Layer of the endocardium layer of the heart
Made up of CT fibers such as elastin, collagen, and conducting fibers

20

Purkinje fibers

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

21

Pacemakers take over for the _______ when it malfunctions.

SA node

22

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

skeleton; valves

23

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

bicuspid; mitral; tricuspid

24

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

fibrous skeleton

25

The heart has _______ innervation.

dual

26

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

sympathetic; parasympathetic; autonomic

27

Sympathetic innervation of the heart

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

28

Parasympathetic innervation of the heart

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

29

Capillaries

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

Pericyte

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

31

Continuous capillary

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

32

Fenestrated capillary

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

Sinusoidal capillaries

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

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

tunics; tunica intima; tunica media; tunica adventitia

35

Tunica intima

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

Tunica media

Middle tunic of a blood vessel
Smooth muscle that recoils and stretches

37

Tunica adventitia

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

38

Internal elastic membrane

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

External elastic membrane

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

40

Vasa vasorum

"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

What regulates the diameter of bv?

Nerve fibers

42

Sympathetic nerve innervation of bv

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

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

tunica adventitia; norepinephrine; smooth

44

Relaxation of bv can be _______ or _______.

passive; active

45

Passive relaxation of bv is due to _______.

lack of norepinephrine when there is no sympathetic innervation

46

Active relaxation of bv is due to _______.

acetylcholine release of parasympathetic innervation

47

Parasympathetic active relaxation of bv

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

SERCA

Ca+ pump on SER
Pumps Ca+ into SER out of muscle cytoplasm

49

Nitric oxide

NO
Toxic
Cells use to communicate

50

Artery

Very thick tunica media
No valves except for semilunar valves of pulmonary artery and aorta

51

Vein

Very thick adventitia
Large veins have modified tunica intima that forms valves

52

Valve

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

53

Varicose vein

Swollen, discolored vein close to skin surface
Can develop phlebitis, which can lead to clots that can become a thrombus and clog vessels

54

Phebitis

Inflammation of a vein