Cardiovascular System Histology Set 1

Front 1

3 layers of cardiovascular system
(innermost to outermost layer)
Vessels
Heart

Back 1

1. Tunica intima - endocardium
2. Tunica Media - Myocardium
3. Tunica Adventitia - Epicardium

Front 2

Where is atherosclerosis initiated?

Back 2

Endothelium

Front 3

Epithelium of Tunica intima?

Back 3

Simple squamous

Front 4

Where is the subendothelial layer and what does it contain?

Back 4

beneath endothelium
contains SM cells

Front 5

Orientation of endothelium and its elements?

Back 5

Longitudinally
same axis as blood flow

Front 6

7 functions of endothelium

Back 6

selective permeability
non-thrombogenic barrier
modulate blood flow and vascular resistance
regulate cell growth
regulate immune response
maintain ECM
lipoprotein metabolism

Front 7

What is the most prominent layer in arteries?

Back 7

Tunica media

Front 8

Tunica media
contents

Back 8

concentric layers of SM
elastic membranes
reticular fiber (type III collagen)
proteoglycans

Front 9

Arrangement of elements in Tunica Media

Back 9

circularly arranged

Front 10

what separates TM from TI?

Back 10

internal elastic lamina

Front 11

Where is ECM in media synthesized?

Back 11

Smooth muscle (SM) cells

Front 12

Elastic lamella trend in arteries

Back 12

Elastic lamella predominates in Aorta
moving away from aorta more SM is found in TM

Front 13

What is the most prominent layer in veins?

Back 13

Tunica Adventitia (TA)

Front 14

Type of collagen in TA CT sheath?

Back 14

Type 1 collagen

Front 15

how do large BV's get nutrients?

Back 15

Vasa vasorum

Front 16

what component of TA regulates SM in the Tunica media?

Back 16

nervi vascularis

Front 17

What are Nervi vascularis

Back 17

vasomotor nerves
network in the TA
innervates SM of tunica media

Front 18

arrangement of Tunica Adventitia?

Back 18

Longitudinally arranged
just like Tunica Intima

Front 19

what is the homologous structure of the TI in the heart?

Back 19

Endocardium - innermost layer

Front 20

the endocardium contains _____ containing purkinje fibers

Back 20

subendocardium

Front 21

What is the subendocardium composed of?

Back 21

Loose CT
elastic and collagen fibers
SM cells

Front 22

Veins, nerves, purkinje fibers and lymphatic vessels are in the subendocardium? T/F

Back 22

F.
only some small veins, nerves, and purkinje fibers

Front 23

what are purkinje fibers?

Back 23

specialized cardiac muscle cell

Front 24

Characteristics of Purkinje fibers

Back 24

larger than ordinary cardiac cell
fewer myofibril (stain lighter)
central (often binucleate) nucleus
prominent glycogen accumulation surrounding nucleus

Front 25

an ischemic attack involving purkinje fibers would result in what?

Back 25

Death
inability for heart to rhythmically contract

Front 26

Describe briefly the electronic conduction of the heart

Back 26

beat is initated at SA node (pacemaker)
AV node picks up beat and sends it along the fibrous skeleton to the AV bundle (Bundle of his)
Bundle divides into R and L bundle branches then to subendothelial branches (Purkinje fibers)

Front 27

describe the muscle contraction of the heart

Back 27

contraction intitiated in atria
forces blood into ventricles
contraction in ventricles begining at apex forces blood through aorta and pulmonary trunk

Front 28

What important feature is located in the subendocardial layer?

Back 28

Purkinje fibers

Front 29

Are purkinje fibers specialized for contraction?

Back 29

NO.
Specialized for conduction of electrical impulse

Front 30

what is myocardium anchored by?

Back 30

Fibrous Cardiac skeleton

Front 31

what is the dense fibrous cardiac skeleton

Back 31

dense CT
Contains:
Four fibrous rings (surround valve orifices)
two fibrous trigones connecting rings
membranous part of interventricular and interatrial septa

Front 32

what is the principal component of the heart?

Back 32

Myocardium

Front 33

what does it mean that heart muscle is postmitotic?

Back 33

focal death of myocardial fibers by ischemia cannot be replaced
Scar tissue formation replaces muscle

Front 34

can you see intercalated disks in myocardium?

Back 34

Yes

Front 35

What is the epithelium of epicardium?

Back 35

Simple squamous

Front 36

Epicardium composition

Back 36

loose CT
adipose tissue
contains arteris, veins and nerves

Front 37

What is the embryological origin of epicardium?
function?

Back 37

mesothelium
allows for smooth movement within pericardial sac

Front 38

what occurs with L ventricular hypertrophy?

Back 38

enlarging of cardiac cells
less distensible
increased systemic resistance

Front 39

the two types of arteries?

Back 39

Large elastic
and
Muscular

Front 40

control of blood flow to capillary networks is done by what?

Back 40

SM in arterioles