Muscular System BIO 515 Sonya Livitz

Hello. My name is Sonya Limits, and I will be

discussing the structure of skeletal muscles so before we dive

into what it is, the skeletal muscle is has many

different functions in the human body that is responsible for

locomotion. Heat, body heat production, a posture regulation of internal

organs, respiration as well as communication, especially between signals coming

from the brain.

But these are not the only muscles found in the

skeletal system.

In fact, we also have the smooth and cardiac muscles.

Smooth muscles are present in the organs, airways and blood

vessels, and they are involved in involuntary movement with one

nuclear Purcell.

And they're not street.

Not being non strategy means that it is basically not

banded. Cardiac muscles are present in the heart, and they're

involved in involuntary movement.

They consist of one nucleus for self, and they are

striated now.

This is similar to a skeletal muscle, because a skeletal

muscle is striated as well, with consistently visible banding.

It also has many nuclear Purcell, and it is involved

in voluntary movement, which is different than the other two.

For example, if you would like to go for a

walk or you would like to drink a glass of

water. This is voluntary, as the signals from your brain

are sending messages to yourselves muscles to contribute to this

movement in a coordinated fashion.

It is also a present around the bone.

There are over about 400 skeletal muscles in the human

body, which takes up a significant amount of the human

body weight.

Now this will be discussed a little bit later on

in the presentation.

But skeletal muscle is composed of muscle fibers, connective tissue

of blood, vessels and nerves, and these fibers are quite

long in form, a cylindrical shape.

Um, they also tend to be smaller and, um, in

small muscles, of course, and definitely larger in larger muscles.

So let's go ahead and go to the anatomy.

So in the anatomy skeletal muscles, air composed of bundles

within bundles, meaning there are many layers to this so

we can see it starts with the muscle, the muscle,

fast sickles, muscle fibers.

In my 05 Brill's, there are two types of my

own Bibles.

There is the Act In and Miles and miles.

Five bills and, um, each of the mild muscle fibers

are suspended side by side, Um, spaces between them are

filled with the circle plasm, so the circle plasm consists

of potassium, magnesium, phosphate and other protein enzymes.

Now my liberals could be found on each end of

the fiber.

They are anchored to the inner surface of circle Emma,

and when these mile fireballs, when they become shorter, the

muscle will also shorter.

I'll become shorter, meaning that it is contracting a ZX

for the circle.

Llama is basically the cellular membrane.

It protects the muscle fibers and contains Onda abundance of

myoglobin. What this means is that it contains many of

the same organelles seen in other cells.

And what this A ZX well is this oxygen binding

protein. It is also consisting of openings of the T

two bills, and these tubes extend into the circle plasm

um, at the surface.

The Circle plasm is known as thesis plasm of the

muscle fiber or the inconsistent intracellular fluid, and it holds

the Maya fibra ls also toe, which we will also

discuss a little bit.

Thea Mile filaments are thin, while the Myerson are thick,

so let's go into the structural functions.

So as we can see in this picture here we

have the nuclei Thean Domizzi, um, paramecium at the museum.

A ZX well, a ZX, the Kalima, fast sickles and

blood vessels.

But we're going to discuss now what the top four

are and what their role is.

So, well, nuclear.

So the skeletal muscle has multiple new client is a

multi nucleus Purcell on the periphery of itself wth e

end. Um, easy.

Um, is known to be the thinner portion.

It surrounds each individual muscle fiber and regulates the metabolic

exchange between the muscles and the blood.

The para museum is surrounding the the bundles of these

fast sickles and it involved in contract tile movement.

As for the FM museum, it surrounds the entire muscle.

It protects it from damage friction that can be caused

with other muscles and bones.

My five bills we discussed consists of SAARC Amir's, and

it is involved in muscle contraction.

Um, circle Emma is basically like a barrier between the

internal and external environments and compartments and the physical is

the muscle Viber helping and determining what kind of muscle

movement will it be?

For example, are we going in a circular motion?

Are we going in a straight motion so it helps

coordinate which direction we're going Now, let's go ahead and

discuss wth E Sarko Plas Mick Ridiculous.

Um, so the circle plasma ridiculous is known to be

the storage of calcium islands consisting of l tubules.

It then functions and pushing these calcium islands out into

the circle Plasm So And it's important to consider how

the sarka plasma ridiculous is different from the end of

plasma Ridiculous, um which isn't responsible for the synthetic for

synthesizing molecules.

The end of class in particular, um, also consists of

rough and smooth, which are different, in which the rough

and new class in particular is bound by ribosomes and

stores proteins, while the smooth it doesn't is not.

It is more irresponsible in sword and lipid and protein

storage. The circle positive particular, um, also spans Sark Amir,

of which we can see in the diagram and thes

different variables that we will go through our part of

the composition of the circle here.

So as we can see here the Z, the Z

line on this diagram or the disc these air the

end of the SAARC Amir's thin acting filaments branch from

these Z lines towards the middle of the SAARC.

Amir the M line is basically the midpoint of the

SAARC Amir Thick Meyssan filaments will branch from the M

lines towards the ends of the SAARC.

Amir three i band is the heir of SAARC Amir,

where only acting filaments are present and then we see

here the A band.

Next to it is the area in the circum era

where the act in my sin will overlap.

As for our last section here, the ages own it

is the area of the circle near where Onley myson

is found to be present.

In addition, we should also consider the motor units.

Motor units are made up of muscles and it refers

to all of the muscle fibers that are innovated by

a single neuron.

So small motor units are involved in only a few

muscle fibers used for precision movement, while the large motor

units are involved in many muscle fibers and they are

integrated by a single neuron but are used in very

powerful movements like punching, for example.

Now let's go ahead, Thio muscle proteins and my vibe

roles Okay, So as we discussed a little bit earlier,

there are thin and thick mile filaments thin consist of

acting with nebula in attachments.

Um, Thio Nebula Attachment, yes, and then thick is basically

consisting of mice in which they have tighten attachments.

As we can see here in this diagram, the Titan

attachments or molecules are able to form elastic filaments that

help to connect thick filaments to the Z line.

As we've shown in the Sarko here, while nebula is

more associated with thin filaments and helps with regulating how

active is affected and its movement Now when we look

at regulatory proteins here we have triple myson and Proponent

triple medicine, prevents any type of contraction in muscle cells

and also acts as a barrier at myosin binding sites

to active molecules.

Troponin, on the other hand, is involved in the attachment

of is also attached.

That should be two T's.

Sorry about that.

To triple myson, um, to place on acting molecules.

Mhm trouble.

Madison also is a wrapped around and acting helix, and

it is, um, covering active sites and the resting phase,

while troponin is going to be made up of three

protein subunits, troponin I, C and T.

It's also important to keep in mind that when we

have any type of muscle contraction, there are many different

changes. We have chemical, we have mechanical, thermal and electrical.

And in mechanical, for example, we haven't isotonic contraction, which

basically means that there is a muscle shortening.

Um, but the volume of the muscle is still staying

the same.

We also happen isometric contraction, in which there is actually

no change in the length of the muscle.

Another example of a changes in thermal, which is like,

for example, activation heat.

This'll involves troponin in which energy needed for a calcium

influx, um, binds to the troponin and pumps out calcium

ions. So this is the final presentation, along with references.

Thank you for listening.

Muscular System BIO 515 Sonya Livitz

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