Histology Exam #1 Cardiac Muscle And Smooth Muscle

Front 1

Cardiac muscles fibers are small, ___ cells and has ___. Adjacent fibers are connected at their ends by junctions (dark zigzagged line) called ____

Each fiber has a oval euchromatic nucleus in the __ of the cell.

Back 1

branched

striations

intercalated disc

center

Front 2

What are the similarites of cardiac muscles and skeletal muscles?

Are the organelles less developed in cardiac muscles?

what is the main difference?

Back 2

1)both have contractile filaments (actin and myosin), myofibrils, and sacromeres with A, I bands, and Z lines and 2) membranous specializations that include sarcoplasmic reticulum with terminal cisternae and tubules

-yes

-Cardiac muscle has a Diad (one t tubule and one cisternae at the Z line

Front 3

(T or f) Cardiac muscles are abundant with myoglobin and mitochondria

( t or F) individuals are not attached to each other with special junctions

Back 3

true

false (they are by intercalated discs)

Front 4

___ and ____ hold adjacent cells together and transmit the force of contraction from cell to cell ____ anchors actin filament of the last sarcomere to the sarcolemma

___ are strong spot attachments that bind neighboring cells.

___ allow the diffusion if ions and electrical excitation between the cells

Back 4

fascia adherens (type of intermediate junction) and desosomes

fascia adherens

desosomes

gap junctions

Front 5

The linking of the individual cells structurally and ionically, allow the cell to contract together as a mass or ____

Cardiac muscles are ____ that is they exhibit a spontaneous rhythmic contraction.

(t or f) there are motor end plates in the cardiac muscle

Back 5

synctium

autogenic

false

Front 6

Purkinje fibers are located in the ___ of the heart. they contain an abundant amount of __ with a few myofibrils. They are specialized to a play a key role in coordinating ___ of the heart. they help set the pace of the contraction by quickly conducting and spreading waves of ____ to other cardiac muscle by gap junctions

Back 6

endocardium

glycogen

the pattern of contraction

excitation

Front 7

Do cardiac muscles replicate?

If portions of the cardiac muscle dies (myocardial infarct) muscle tissue is replaced by what?

Back 7

no

CT

Front 8

hypertension can lead to ___ off the cardiac muscle if the increased functional demands on the heart to maintain the high blood pressure leads to a massive increase in cell and heart heart size

Back 8

hypertrophy

Front 9

Where is smooth muscle commonly found?

Smooth have __ spindle shaped cells

Each fiber has how many central nucleus?

Are there any striations?

Back 9

in the walls of tubes (blood vessels, airways) and hollow organs (gut, uterus)

acidophilic

one

no

Front 10

(True or false) myofilamets are present and is organized into myofibrils, sarcomeres, a and I bands in smooth muscle

In smooth muscle, the filaments interconnect and are anchored to ___ that in turn are anchored to the sarcolemma

Back 10

false, they are not

dense bodies

Front 11

Do smooth muscles cells have specialized membrane system (organelles)? they have small invaginations called ___ , and ___ are prevalent in the cytoplasm

Are there any specialized motor end plates in smooth muscle? what are they often linked by?

Back 11

No

caveolae

pinocytotic vesicles

no

gap junctions

Front 12

(T or f) Most of the smooth muscle tissue can spontaneously contract, although the autonomic nervous system and hormones of the endocrine system can modify the rate of contraction

Back 12

true

Front 13

Smooth muscle can undergo __ and ___

*smooth muscle divide to maintain its number, new smooth muscle can develop from existing smooth muscle cells, or undifferentiated stem cells or from pericytes associated with blood vessels*

Back 13

hyperplasia, hypertrophy

Front 14

Can smooth muscle proliferation and extracellular matrix (fibers and proteogylcans) deposition play an important role in the formation of atherosclerosis lesions in the walls of blood vessels?

Back 14

yes

Front 15

___ are malignant tumors derived from smooth muscles. they are most found in the pelvic organs (especially the uterus) and blood vessels. These rare tumors usually occur in adults

__ are malignant tumors that resemble developing skeletal muscle cells. they usually occur in the arms and legs. this rare tumor is typically present in children (1 through 6)

Back 15

Leiomysarcomas

Rhabdomyosarcomas