A fascicle in general is a bundle or cluster of things. Very generally in medicine commonly mentioned fascicles include nerve fascicles (a bundle of axons) and muscle fascicles (a bundle of skeletal muscle fibers)
The spinal cord is composed of both the grey matter "horns" and the white matter surrounding it. In the white matter are the myelinated axons, and the grey matter contains mainly the cell bodies of the axons that project their fibres up and down.
Fascicles, or tracts, are groups of neurons that convey specific information about a particular area in your body, either up to your brain (sensory, or referred to as ascending tracts), or from your brain to your muscles (motor, also referred to as descending tracts). There are multiple different tracts responsible for different things. A fascicle is just another word for a tract.
To take a couple of examples, let us quickly run through a couple of important tracts. In the dorsal funiculus (a funiculus is a GROUP of fasciculi, don't get confused!) there is the gracile fasciculus and the cuneate fasciculus. They convey proprioceptive information, vibration and discriminative touch from the lower and upper limbs respectively, hence they are ascending pathways. If you wish to know more about specific tracts then let me know as there will be a lot to go through!!
Another example, this time of a descending tract, is located in the lateral funiculus, and is known as the lateral corticospinal tract. This tract consists mainly of the 90% of fibres that cross over from the primary motor cortex, and is responsible for skilled voluntary movements. Interestingly enough, the lateral corticospinal tract in the upper limb is highly developed due to the amount of control that we have to have over our fingers!
Images are by far the best way to study the individual tracts of the spinal cord, PM me if you have any more questions on the many other different tracts in the spinal cord. :)
Fascicles are bundles or clusters of nerve or muscle fibers.
As a fascicle is made up of many muscle fibers, as each muscle fiber contract as a whole- a greater contraction is generated.
In anatomy, a fascicle is a bundle of skeletal muscle fibers surrounded by perimysium, a type of connective tissue.
A bundle of fibers (especially nerve fibers)
The arrangement of the fascicles in orbicularis oris is circular.
Muscle fibers are grouped into fascicles, these fascicles form a muscle. The fascicles are arranged in 3 basic patterns. Parallel fascicles are arranged length wise in a parallel form. Circular fascicles are arranged in rings in a concentric pattern. Pennate fascicles are arranged in a feather pattern, with muscles arranged like a feather attached to a tendon along its length.
In forming whole muscles, individual muscle fibers are arranged in bundles, or fascicles, held together by fibrous connective tissue.Answer is Fascicles.
Perimysium is the connective tissue that divides the muscle into fascicles.
perimysium
no
Fascicles
nope!
fascicles are wrapped in perimysium
Parallel
Fascicles
no