HISTOLOGY L5

mesoderm

origin of muscle tissue

movement
maintenance of posture
joint stabilization
heat generation

functions of muscle tissue

due to Mitochondria producing ATP

(heat generation): during contraction, what is the reason why our muscle tissues produce heat?

IV

the ff are the general characteristics of muscle tissue, except?

I. contractility
II. excitability
III. extensibility
IV. flexibility
V. elasticity

contractility

vital protoplasmic property that is highly developed in
muscle tissue

they shorten the muscle

during contraction, what do they do the muscle?

a pulling force

(contractility): shortening generates?

the nerve fibers attached
to the muscle

the muscle tissue excites itself due to?

sciatic nerve

for muscle nerve preparation, what causes contraction?

gastrocnemius muscle

what stimulates the sciatic nerve?

excitability

cause electrical impulses that travel into the muscle
tissues, thus can cause contraction

excitability

Nerve fibers cause electrical impulse to travel

extensibility

As the muscle stretches. It contracts with the contraction of an
opposing muscle

extensibility

Stretch with contraction of an opposing muscle

elasticity

period of relaxation is the ________ of the muscle tissue

passively

elasticity recoils ____ after being stretched

f, no against

(t or f): one of the characteristics of the muscle fiber is that it is elongated AGAINST in the direction of the action.

all are included

the ff are the organelles found in the cytoplasm of the muscle tissue, except?

I. cell membrane
II. fibrils
III. smooth ER
IV. mitochondria
V. sarcoplasma

muscle fibers

muscle cells are now termed as?

smooth muscle
cardiac muscle
skeletal muscle

3 types of muscles

direction of the action

the elongation of the muscle fiber is based on the?

f, parallel

(t or f): elongation of the muscle fiber basing on the direction of the action means that it is PERPENDICULAR to their long axis of contraction.

t

(t or f): the shape of the nucleus of the muscle cell VARIES OR CONFORMS to the shape of the cell.

f, the # of nuclei varies bc it is DEPENDENT on the type of muscle

(t or f): the number of the nuclei of muscle tissue is INDEPENDENT on the type of muscle.

sarcoplasm

cytoplasm is also termed as?

strongly acidophilic

H&E stain of the cytoplasm of muscle tissue?

due to the staining reaction of the myoglobin pigment

why is it strongly acidophilic?

sarcolemma

cell membrane is termed as?

I - ii, II - i, III - iii

associate.

I. sarcoplasm
II. sarcolemma
III. sarcosomes

i. cell membrane
ii. cytoplasm
iii. mitochondria

myofibrils

the fibrils are known as?

fibrils

smallest contractile elements of the
muscle cell or the muscle fiber

sarcoplasmic reticulum

smooth ER of muscle tissue is termed as?

simple or extensive

smooth ER could either be ____ depending on the muscle type

smooth ER

its function can either be for cell circulation and spread of excitation

mitochondria

produces ATP

sarcosomes

mitochondria is termed as?

accommodate the high energy requirement during contraction (bc of heat generation)

numerous mitochondria in order to?

functional
structural

classification of muscle tissue

functional

Either voluntary or involuntary

structural

Either striated or unstriated

smooth muscle
cardiac muscle
skeletal muscle

3 histologic types of muscle tissue

smooth muscle

(type): it is unstriated and involuntary

muscle fiber

structural and functional unit of smooth muscle

V

occurrence of smooth muscle, except?

I. hollow organs of the body
II. genitourinary tract
III. ureter, urinary bladder, renal pelvis, renal calyces
IV. blood vessels and respiratory tract
V. attached to bone

smooth muscle

the tissue of the walls esp in muscularis portion is?

ileum

L section of smooth muscle specimen

spindle-shaped - broad/wide middle portion with tapered end

L section of smooth muscle shape of the cell

elongated, centrally located

L section of smooth muscle nucleus

Thin tapered end
attached to the thick middle portion of the neighboring cell
or adjacent cell

L section of smooth muscle nucleus arrangement of muscle cells/fibers

location

the size of smooth muscle fibers in its cross section varies in?

cross section is small

smooth muscle cross section: cutting at the tapered ends?

larger cross section

smooth muscle cross section: cutting transversely (middle portion)?

the nuclei appears

when x section is cut on the thick portion transversely, what appears?

t

(t or f): NOT ALL CELLS in the smooth muscle (x section) have nuclei.

f, larger cross section

(t or f): Only the SMALLER CROSS SECTION has a centrally located nuclei.

Nexus or Fusiform Densities

Appearance in Long Section

Nexus or Fusiform Densities

localized thickening of the apposed cell
membrane

Myofibrils
Myalgia or Border Fibrils
Contraction bands or nodes

fibrils in smooth muscle

t

(t or f): you CANNOT APPRECIATE the longitudinal striation of smooth muscle due to the arrangement of its myofibrils.

t

(t or f): myofibrils are STILL PRESENT in smooth muscle.

unstriated

the myofibrils in smooth muscle is classified as?

bc the longitudinal striation is not prominent

why are the myofibrils classified as unstriated in smooth muscle?

the periphery of the
muscle fiber/muscle cell.

where is the myalgia or border fibrils located in smooth muscle?

periphery

near the
sarcolemma or the cell membrane

f, reticular, and elastic fibers not obvious

(t or f): one muscle fiber (in the smooth muscle) is surrounded by a delicate, GRANULATED, AND COLLAGEN FIBERS OBVIOUS to the L/M.

border fibrils

(smooth muscle): acts as a
cytoskeleton, so therefore, helps straighten the muscle
after contraction

contraction bands or nodes

transverse dark lines that can be seen only if the
living muscle cells/fibers are fixed during contraction

no

are contraction bands or nodes identifiable in the slide stained with H&E even if its a fixed specimen?

yes

is smooth muscle also found in esophagus (lower)?

spindle-shaped

muscles of the smooth muscle tissue are _______ cells

one centrally located nucleus

nucleus of smooth muscle has ___________

elongated

smooth muscle nucleus: L section

round

smooth muscle nucleus: X section

grouped into sheets

smooth muscle is ________, often running PERPENDICULAR to each other

t

(t or f): there is PERISTALTIC MOVEMENT in smooth muscle

f, no striations (no sarcomeres)

(t or f): smooth muscle HAS STRIATIONS

slow
sustained
resistant to fatigue

contractions in smooth muscle are?

synaptic fatigue

when the sciatic nerve is stimulates the gastrocnemius muscle contracts
but dali ra sya muhunong, so it's not resistant to
fatigue

f, does not always

(t or f): smooth muscle ALWAYS require a nervous signal

stretching or hormones

smooth muscle can be stimulated by _______

inside the eye
walls of vessels
respiratory tubes
digestive tubes
urinary organs
reproductive organs

6 major locations of smooth muscle

sarcomere

Structural and Functional Unit of skeletal muscle

f, DOES NOT INCLUDE

(t or f): occurrence of skeletal muscle INCLUDES the intrinsic muscle of the tongue and
some muscles for facial expression.

multinucleated cells

fibers of skeletal muscle

long, solitary band; they are non
branching fibers

fibers for skeletal muscle appearance

Roughly cylindrical in shape

fiber shape in skeletal muscle

f, longitudinal

(t or f): fibers in skeletal muscle is prominently cross-banded (CROSS striations)

has cells with striations

skeletal muscle has/does not have cells with striations?

voluntary

the contractions in skeletal muscle is voluntary or involuntary?

striated and voluntary

classification of skeletal muscle?

In the "Periphery" (the perimeter of a circle)

Location of Nucleus in the cross section of the skeletal muscle?

2 nuclei (bc its multinucleated) in one x section

Appearance of Tongue in Cross Section, for its sarcolemma?

rough appearance with fine dots

sarcoplasm for tongue in x section appearance

condensed area/field

myofibrils in x section appearance

A, I, H, M, and Z lines

L section of skeletal muscle different bands

I - II - III

the L section of a skeletal muscle has the following:

I. Conheim's area
II. Different bands
III. Sarcoplasmic reticulum

Anisotropic Band

A band

Anisotropic Band

"Dark staining Band"

"H Zone"

A band has been dissected by pillar zones known as ____________

M line

Direct line that is center of the H Zone