Home Site Map Contact Us
Rapid Learning Member Login  
Rapid Learning Blog Rapid Learning on Facebook Rapid Learning on Youtube Rapid Learning on Twitter
 How to Learn in 24 Hours?

 Need Help?
M-F: 9am-5pm(PST):
Toll-Free: (877) RAPID-10
or 1-877-727-4310

24/7 Online Technical Support:
The Rapid Support Center

Secure Online Order:
Buy Now


 Got Questions?
Frequently Asked Questions
 Need Proof?
Testimonials by Our Users

Trustlink is a Better Business Bureau Program.
Rapid Learning Center is a fivr-star business.

External TrustLink Reviews

 Member Login:
User ID: 

 Rapid Learning Courses:

MCAT in 24 Hours (2021-22)

USMLE in 24 Hours (Boards)

Chemistry in 24 Hours

Biology in 24 Hours

Physics in 24 Hours

Mathematics in 24 Hours

Psychology in 24 Hours

SAT in 24 Hours

ACT in 24 Hours

AP in 24 Hours

CLEP in 24 Hours

DAT in 24 Hours (Dental)

OAT in 24 Hours (Optometry)

PCAT in 24 Hours (Pharmacy)

Nursing Entrance Exams

Certification in 24 Hours

eBook - Survival Kits

Audiobooks (MP3)

Have friends taking science and math courses too? Tell them about our rapid learning system.

Muscles and Muscle Tissue

Topic Review on "Title":

Muscles are organized into three basic types:

  1. Striated: Skeletal muscle facilitates movement by applying forces to bones and joints through its contraction.  They are generally under voluntary control. Muscles have an origin; a thick portion of the muscle between the insertion and origin is called the muscle belly or gaster and a tendon.
  2. Cardiac: Cardiac muscle is an involuntary striated muscle found exclusively in the heart. Cardiac muscle has unique properties; it stimulates its own contraction without the required electrical impulse from the central nervous system via special pacemaker cells in the sinoatrial node.
  3. Smooth: Smooth muscle is an involuntary non-striated muscle found in the walls of hollow organs such as the bladder, and in blood vessels. Smooth muscle can be directly stimulated by the CNS or can react to hormones secreted locally, such as vasodilators and vasoconstrictors.

Skeletal muscle fiber

  • Anatomy: Skeletal Muscle Fibers are made up of many myofibrils surrounded by sarcoplasmic reticulum. The sarcolemma is on the outside of the muscle fiber and contains many nuclei.
  • Sarcomere: The dark striations of skeletal muscle are made up of a lattice of thick and thin filaments, which are formed into a functional unit of contraction known as the sarcomere. Sarcomeres are the basic unit of muscle, made up of actin and myosin.
  • Sliding filament model: Sliding filament model: after the signal to contract comes from the central nervous system, an action potential spreads over the muscle fiber.

Physiology of contraction

  • Excitation-Contraction coupling: Excitation-Contraction coupling is the process by which an action potential causes calcium (Ca2+) release and cross bridge cycling. An incoming action potential, transmitted through the neuromuscular junction, causes the depolarization of the skeletal muscle cell.
  • Length-Tension Relationship: The amount of tension (force of contraction) a skeletal muscle creates is dependent, in part, on the length of the muscle itself. The optimal length for a muscle is when the maximum number of myosin cross bridges make contact with thin filaments.

Muscle metabolism

  • Breakdown of ATP: when a muscle is stimulated to contract, the initial ATP (stored as phosphocreatine) is the initial energy source, lasting seconds.
  • Anaerobic Glycolysis: when the phosphocreatine source is depleted, muscle converts glucose into pyruvic acid and ATP.
  • Aerobic Glycolysis: if sufficient oxygen is available muscle tissue will convert glucose into CO2, H2O and ATP to use as energy.
  • Lipolysis: during long periods of exercise, muscle can use the byproducts of fat breakdown, which are free fatty acids (FFA). FFA are converted into ATP.

Types of Skeletal Muscle Fibers: There are 3 main types of skeletal muscle:

  1. Slow Oxidative Fibers
  2. Fast Oxidative-Glycolytic Fibers
  3. Fast Glycolytic Fibers.

Most skeletal muscles are a mixture of all 3 types.

Control of muscles

  • Neuromuscular junction: Motor neurons axons connect with muscle fibers via a neuromuscular junction. The axon ends at the neuromuscular junction and is separated from the muscle fiber itself by a synaptic cleft. Neutortansmitters such as acetylcholine, cross the synaptic cleft and transmit the chemically converted electrical impulse to the muscle causing it to contract.
  • Voluntary muscles: broadly only skeletal muscles are under voluntary control. Meaning we can contract the muscles at will.
  • Involuntary muscles: Involuntary muscles are rhythmic, automatically controlled muscles. The muscles of breathing are under both voluntary and involuntary control. Cardiac (heart) muscle is under involuntary control. The pacemaker cells in the sinoatrial node set the rate and the autonomic nervous system can modulate that rate. Smooth muscles in the walls of organs and blood vessels are primarily under involuntary control.

Rapid Study Kit for "Title":
Flash Movie Flash Game Flash Card
Core Concept Tutorial Problem Solving Drill Review Cheat Sheet

"Title" Tutorial Summary :

Muscles are key to providing strength and movement to the body, as well as providing organ function and the ability to modulate systemic blood pressure.  Muscles are controlled by the nervous system and the signals to contract are transmitted through the neuromuscular junction.

Tutorial Features:

Specific Tutorial Features:

  • Step by step details are shown to describe how the individual sarcomere and eventually the entire muscle contract.
  • The various types of muscles and their unique function in the body are presented.

Series Features:

  • Concept map showing inter-connections of new concepts in this tutorial and those previously introduced.
  • Definition slides introduce terms as they are needed.
  • Visual representation of concepts
  • Examples given throughout to illustrate how the concepts apply.
  • A concise summary is given at the conclusion of the tutorial.

"Title" Topic List:

Muscles are organized into three basic types:

  • Striated
  • Cardiac
  • Smooth

Skeletal muscle fiber

  • Anatomy
  • Sarcomere
  • Sliding filament model

Physiology of contraction

  • Excitation-Contraction coupling
  • Length-Tension Relationship

Muscle metabolism

  • Breakdown of ATP
  • Anaerobic Glycolysis
  • Aerobic Glycolysis
  • Lipolysis

Types of Skeletal Muscle Fibers

Control of muscles

  • Neuromuscular junction
  • Voluntary muscles
  • Involuntary muscles

See all 24 lessons in Anatomy and Physiology, including concept tutorials, problem drills and cheat sheets:  Teach Yourself Anatomy and Physiology Visually in 24 Hours

© 2021 Rapid Learning Inc. All rights reserved         Disclaimer | Privacy Policy