Module 3 (Types of Muscles) Flashcards
What are the 3 types of muscles
Skeletal, cardiac, and smooth
What kind of organs are muscles
Contractile organs
Through muscle contraction, what can these organs do
Perform a number of important functions such as movement
Characteristics of skeletal muscles
Help the body move
Voluntary
Attached to bones via tendons
Striated
Multi-nucleated and peripherally located
Long, cylindrical/rod like
Characteristics of cardiac muscles
Found in the heart
Involuntary
Contracts rhythmically, modulated by neural activity and hormones
Striated
Contain intercalated discs
Uni/binucleated, centrally located
Small and branched
What causes striations
Arrangement of actin and myosin filaments within myofibrils
Characteristics of smooth muscles
Controlled by the nervous system and hormones
Involuntary
May be inactive and respond to stimulation or may be rhythmic
Not striated
Uninucleated, centrally located
On the walls of hollow organs
Shape of smooth muscles
Fusiform meaning they are wide in the middle and taper off at the ends
How can muscles be characterized
Based on morphology (form) or how they function
What are intercalated discs
Connects heart muscle cells to each other
What are voluntary muscles
Muscle that is consciously controlled in order to perform a specific function
Ex. skeletal muscles
What are involuntary muscles
Muscles that are not consciously controlled
Ex. smooth and cardiac muscles
How do muscles function
They have 2 basic properties
Excitability and contractility
What is excitability
The ability of muscle tissue to receive and respond to electrical signals from nerves or stimulation from hormones
What is contractility
When a muscle cell is excited by a nerve or hormone, this causes the muscle to shorten, resulting in contraction
