What are the different types of motor units?
Based on contractile speed, motor units are classified as either slow-twitch (S) or fast-twitch (F). The F motor units are further subdivided into fast-twitch fatigue-resistant (FR), fast-twitch fatigue-intermediate (Fint), and fast-twitch fatigable (FF).
Why is Alpha Gamma Coactivation important?
Alpha-gamma coactivation ensures that muscle spindles maintain sensitivity to stretch over a wide range of muscle lengths.
What is the difference between Extrafusal and Intrafusal muscle fibers?
Muscles have receptors for stretch and force. Extrafusal muscle fibers comprise the bulk of muscle and form the major force-generating structure. Intrafusal muscle fibers are buried in the muscle, and they contain afferent receptors for stretch, but they also contain contractile elements.
What are the four types of motor unit pathologies?
The disease can be classified into four main types depending on the pattern of motor neurone involvement and the part of the body where the symptoms begin.
- Amyotrophic lateral sclerosis (ALS)
- Progressive bulbar palsy (PBP)
- Progressive muscular atrophy (PMA)
- Primary lateral sclerosis (PLS)
What is a Type 2 motor?
Type II motor units are called fast-twitch motor units because of this quicker response time. Another common name is the phasic motor unit, because Type II motor units are recruited after Type I motor units to provide short bursts, or phases, of higher muscle tension as required.
What does Coactivation mean?
Activation of two or more things together. noun. (genetics) A process wherein RNA transcription is increased by a coactivator protein. noun. (medicine) The activation of one muscle coordinately with another.
What is alpha and gamma Coactivation?
Alpha-‐gamma coactivation is a way the muscle maintains this length. As the muscle contracts and relaxes, the sensory neuron relays information to the central nervous system about the change in muscle status. As the central nervous system receives the information, the alpha and gamma motor neurons are activated.
What is an Extrafusal muscle fiber?
Extrafusal muscle fibers are the standard skeletal muscle fibers that are innervated by alpha motor neurons and generate tension by contracting, thereby allowing for skeletal movement. Extrafusal muscle fibers can be generated in vitro (in a dish) from pluripotent stem cells through directed differentiation.
What is Golgi tendon?
Golgi tendon organs (GTOs) are proprioceptors that are located in the tendon adjacent to the myotendinous junction. The Golgi tendon organ is a tree-like sensory ending enclosed in a spindle-like connective tissue capsule, that lies near the junction of a tendon with a muscle.
Do Intrafusal fibers contain actin and myosin?
Just like extrafusal muscle fibers, intrafusal muscle fibers have contractile proteins like actin and myosin.
What are Extrafusal muscle fibers?
Extrafusal muscle fibers are the standard skeletal muscle fibers that are innervated by alpha motor neurons and generate tension by contracting, thereby allowing for skeletal movement. They make up the large mass of skeletal striated muscle tissue and are attached to bone by fibrous tissue extensions (tendons).
Can I teach an IB course?
You are familiar with the IB subject guide (including assessment procedures and moderation) and would like greater confidence before teaching a course. You have inherited a course and would like to review the subject content before teaching it to suit your own style and expertise.
How many classes are there in the IB?
However, these are all the classes the IB has created a curriculum and test for. There are in total 57 classes (counting HL and SL separately). I have categorized them by the categories that the IB defines as the six subject groups.
What is an IB Category 3 workshop?
The International Baccalaureate® (IB) has three categories of workshop based on your experience level, circumstances and professional goals. Category 1 focuses on IB philosophy and implementation. Category 2 covers delivery of the four IB programmes of education. Category 3 builds on and enhances professional development portfolios.
Are you familiar with the IB Subject Guide?
You are aware of the IB philosophy and programme structure but are not experienced in teaching or administrating the IB. You are familiar with the IB subject guide (including assessment procedures and moderation) and would like greater confidence before teaching a course.