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Muscular system

12 videos
3B: Muscles never sleep (literally). If you have ever taken a breath, you have benefited from the work of the diaphragm, which contracts to create an area of low pressure within your thoracic cavity, allowing air in. How exactly are some weightlifters able to support 717 lbs without breaking anything more than a little sweat? Fun fact: the largest muscle in your body is the gluteus maximus (that’s your butt) while the smallest skeletal muscle is the stapedius (it stabilizes the smallest bone, the stapes, which is in your middle ear). By Raja Narayan.

Myosin and actin

VIDEO 9:38 minutes
How myosin and actin interact to produce mechanical force.

Tropomyosin and troponin and their role in regulating muscle contraction

VIDEO 9:22 minutes
Tropomyosin and troponin and their role in regulating muscle contraction. How calcium ion concentration dictates whether a muscle is contracting or not.

Role of the sarcoplasmic reticulum in muscle cells

VIDEO 14:42 minutes
The role of the sarcoplasmic reticulum in controlling calcium ion concentrations within the muscle cell.

Anatomy of a muscle cell

VIDEO 12:42 minutes
Understanding the structure of a muscle cell. By Raja Narayan.

Three types of muscle

VIDEO 11:29 minutes
Understanding the structure of a muscle cell.

Motor neurons

VIDEO 7:19 minutes
How do neurons help us move? Learn about how motor neurons send signals to muscle cells and what happens when we damage this precious neurons. By Raja Narayan.

Neuromuscular junction, motor end-plate

VIDEO 9:00 minutes
How do neurons talk directly to muscle cells? Learn about how a neuronal message is translated into a muscular action at the neuromuscular junction. By Raja Narayan.

Type 1 and type 2 muscle fibers

VIDEO 9:09 minutes
What's the difference between type 1 and type 2 muscle fibers? Learn one golden rule that will help you easily distinguish between them. By Raja Narayan.

Calcium puts myosin to work

VIDEO 10:03 minutes
See exactly how Calcium binds Troponin-C and allows Myosin to do some work.

Muscle innervation

VIDEO 5:14 minutes
Which muscles do we voluntarily control? Which muscles do we have NO control over? What's the difference between sympathetic and parasympathetic innervation? Learn about how our brain splits its control over the body into autonomic and ...

Autonomic vs somatic nervous system

VIDEO 3:48 minutes
Understand the different divisions of the brain that control our muscles.  By Raja Narayan.

Thermoregulation by muscles

VIDEO 8:23 minutes
Why do we shiver when it's cold? How do our muscles make sure we don't freeze or have a heat stroke? Learn how the skin, brain, blood vessels, and muscles work together to maintain our core body temperature.  By Raja Narayan.