Muscle TissueWhich way to the anatomy classroom?... This way…

Introduction

• Lets be very honest…• Many of the things that define

us as humans and as individuals are based on muscular movements• The ability to walk upright• The ability to play sports• The ability to play the saxophone• The ability to talk a selfie

Introduction

• Here is an unconventional example• My friend Jon is a professional

eater• The muscles that he uses defines

what he does• In fact we often talk about the

different types of muscles that could help him in his competitions

Muscle Tissue

• Muscle tissue is designed to help movement of the body or in the body• It is a diverse set of tissue that is

specialized for contraction• This contraction will pull on two

anchored bases and will allow for movement

Muscle Tissue

• There are three main types of muscle tissue• Skeletal Muscle• Cardiac muscle• Smooth Muscle

• These three different types of muscles are responsible for the entire movement system of the body

Skeletal Muscle

• Skeletal muscle is composed of large muscle cells that are designed to make strong contractions• It is a significant amount of your

body weight• 42% in men• 36% in women

Skeletal Muscle

• Skeletal muscle cells can be up to one foot in length• Single muscle cells are often

called muscle fibers• Muscle fibers are often bundled

with other muscle fibers to increase their strength and resistance to damage• These bundles give your muscle

a striped or striated appearance

Skeletal Muscle

• Skeletal muscles are controlled by the nervous system• This means that for a skeletal muscle

to contract a signal must come from a set of nerves• Since you have a large amount of

control over your nerves, you have a large amount of control over your muscle fibers• This means most of your muscle

movements come from striated voluntary muscle

Cardiac Muscle Tissue

• Ok… lets try an experiment• On the count of three I would

like everyone to try to make their heart stop beating for three seconds• This is not long enough for a

change in our bodies• Ready…• Set…• Go!

Cardiac Muscle Tissue

• Cardiac muscle tissue is located in the heart and is designed for long term involuntary use• These cells are designed to

contract many times a minute for the entirety of a human life• When they decide to take a 10

minute break… an organism dies• Cardiac muscle cells are referred

to as cardiocytes

Cardiac Muscle Tissue

• Cardiac tissue anchors on itself so it forms very strong interconnections with itself• This creates branching networks

of muscle cells that are interconnected• These connections occur at

places called intercalated discs

Cardiac Muscle Tissue

• Cardiac muscle cells do not wait for a nerve stimulus to start a contraction• Instead they use a signal that is

generated from a group of cells called pacemaker cells• These cells monitor the level of

blood needed in the body and send impulses that cause the heart to beat

Smooth Muscle Tissue

• Smooth muscle tissue is involuntary muscle tissue located in the walls of hollow organs • These muscles are designed to

create both short and long contractions that are not controlled the organism• Imagine how much concentration

and effort it would take for someone to control food from their mouth until it left them as waste

Smooth Muscle Tissue

• The smooth muscle tissue that lines the body is controlled by the nerves in the brain• However the part of the brain

that controls the smooth muscle tissues is at the base of the brain • This is the area of the brain that

we have very little (almost no) control over

Smooth Muscle Tissue

• Smooth muscle is often found in flat sheets that line organs• If it was bulky it would block

these hollow organs• This means that it does not

bundle the same way that skeletal muscle does• Because of the lack of muscle

control by the brain and the lack of bundles of fibers smooth muscle is referred to as nonstriated involuntary muscle