Master Skeletal Muscle Contraction Action with Picmonic for Pre-Health

With Picmonic, facts become pictures. We've taken what the science shows - image mnemonics work - but we've boosted the effectiveness by building and associating memorable characters, interesting audio stories, and built-in quizzing.

DOWNLOAD PDF

Recommended Picmonics

Skeletal Muscle Contraction Initiation

Macroscopic Bone Structure

Muscle Types

Skeletal Muscle Contraction Action

Skeleton-Muscle-Man flexing his Muscle

Picmonic

Skeletal muscle contraction action describes the process by which the muscle contracts, starting with calcium binding to troponin. The calcium enters the cell through the opening of voltage-gated calcium channels and binds to troponin within muscle cells. This causes an allosteric shift that moves tropomyosin and exposes the active binding site on actin. The myosin head binds to the active site and uses ATP hydrolysis (and phosphate release) to drive a conformational change, which results in myosin pulling on actin, an action also known as the power stroke. Finally, the release of ADP causes the myosin head to disengage from actin. This process results in large amounts of ATP consumption, so muscle cells must have many mitochondria producing ATP to adequately keep up with energy demand.

7 KEY FACTS

An action potential in a motor neuron leads to acetylcholine release. Acetylcholine binds with receptors on the muscle fibers, opening sodium channels, with release of calcium. Calcium influx from voltage-gated calcium channels results in calcium binding to troponin on the muscle fiber.

The calcium binding causes an allosteric change in troponin, shifting tropomysin, which was blocking the active site. This movement exposes the binding sites on the actin filament.

The power stroke of contraction requires ATP, so to keep up with muscle demands for ATP there are many mitochondria producing ATP in muscle cells.

The myosin head binds to the newly available active site, initiating the power stroke. They do so by breaking down ATP to ADP and a phosphate group.

The power stroke occurs when multiple myosin molecules generate force through ATP hydrolysis, which causes a conformational shift and myosin to pull against actin.

The release of the ADP allows the myosin head to unbind from the active site on actin, until more ATP hydrolysis occurs with another power stroke.

Many ATP are consumed for ATP hydrolysis, which allows the power stroke and muscle contraction to occur.

DOWNLOAD PDF

Take the Skeletal Muscle Contraction Action Quiz

Picmonic's rapid review multiple-choice quiz allows you to assess your knowledge.

It's worth every penny

See more reviews

Picmonic for Pre-Health Covers

Pre-Health
200+ Videos
1,000+ Facts

*Average video play time: 2-3 minutes

Anatomy:
50+ Videos

Biochemistry and Genetics:
30+ Videos

Biology:
30+ Videos

Chemistry:
3 Videos

Human Physiology:
60+ Videos

Microbiology:
1 Video

Physics:
6 Videos

Psychology:
30+ Videos

Search for a specific Video or category now!

Or create your own Picmonic

Our Story Mnemonics Increase Mastery and Retention

Memorize facts with phonetic mnemonics

Unforgettable characters with concise but impactful videos (2-4 min each)

Ace Your Pre-Health Classes & Exams with Picmonic:

Over 1,880,000 students use Picmonic’s picture mnemonics to improve knowledge, retention, and exam performance.

Choose the #1 Pre-Health student study app.

Picmonic for Pre-Health covers information that is relevant to your entire Pre-Health education. Whether you’re studying for your classes or getting ready to conquer the MCAT, we’re here to help.