Week 4 // Muscular Tissue AND Muscular System Flashcards
What are the 3 types of muscular tissue?
Skeletal muscle
Cardiac muscle
Smooth muscle
What is the function and location of skeletal muscles?
Skeletal, function is to move bones.
What is the function and location of cardiac muscles?
In heart, function is to pump blood.
What is the function and location of visceral (smooth) muscles?
various organs, various functions (ex. paristalsis)
What is the appearance of skeletal, cardiac and smooth muscle tissue?
skeletal: multi-nucleated and striated
cardiac: one nucleus, striated, intercalated disks
What are the functions of muscular tissue?
- Generating heat
- Producing body movements
- Stabilizing body positions
- Storing and mobilizing substances within the body
(In a less known but critically important role, muscle influences energy and protein metabolism throughout the body. Muscle is a primary site for glucose uptake and storage, and it is also a reservoir of amino acids stored as protein.)
Properties of muscular tissue?
- Electrical excitability
- Contractility
- Extensibility
- Elasticity
How are muscles formed?
Myoblasts
How do skeletal muscles produce movements?
Skeletal muscles produce movements by exerting force on tendons
Tendons attach to and pull on bones, and movement occurs
Origin and Insertion
When a muscle contracts, it draws one articulating bone toward the other
Origin – the attachment to the stationary bone
Insertion – the attachment to the moveable bone
Lever Systems and Leverage
Levers are acted upon by ____ and ________
The lever is acted on by:
Load (Resistance)
Effort
Bones serve as levers and joints serve as
________
fulcrums
What is a lever?
Lever is a rigid structure that can move around a fixed point called a fulcrum
First Class Lever
Load and effort on opposite sides of fulcrum.

Second Class Lever
Load and Effort on same sides as fulcrum, the effort is farthest away from fulcrum.
(wheelbarrel)

Third Class Lever
Load and Effort on same sides as fulcrum.
Load is farthest away from fulcrum.
(Picking something up, biceps)

How are most skeletal muscles arranged?
most skeletal muscles are arranged in opposing pairs at joints
Agonist/prime mover
biceps brachii (add from text)
Antagonist
Triceps brachii muscle must relax to allow biceps to move
Synergist
During forearm flexion, for example lifting a cup, a muscle called the biceps brachii is the prime mover. Because it can be assisted by the brachialis, the brachialis is called a synergist in this action
(Smaller muscles that help Agonist and Antagonist muscles to finish movements)
How are muscles named?
A muscle may be named based on:
Location
Size
Number of origins
Appearance
Direction of fibres
Origin and insertion
Muscle action
Rectus
Parallel to midline
Transverse
Perpendicular to midline
Oblique
Diagonal to midline












































































