Respuesta :
Answer and explanation;
Skeletal muscles;
- The primary function is to attach to and move skeleton
- Skeletal muscles consist 40% of the body weight
- They have fibers with multinucleated cells (embryonic cells fuse)
- Nuclei pushed off to the side
- Cells have obvious striations
- Contractions voluntary
Smooth Muscles
- Cells spindle shaped with one central nucleus.
- They are grouped into sheets (often perpendicular to each other)
- They have no striations (no sarcomeres)
- Their contractions slow, sustained, and resistant to fatigue
- They do not always require nervous signal.
- They aid the process of peristalsis
- They provide multiple functions to organs (ex. change diameter and length of tubular organs)
- They are usually on organs that need sustained/regular contractions
Cardiac muscles
- They are only located in the heart
- Their function: reduce size of chambers of the heart (atria/ventricles)
- They have a system of contractile proteins (ie. sarcomeres) and sarcoplasmic reticulum similar to skeletal muscle
- They differ in that; they have single cells, intercalated sics, 1-2 nuclei in center, inherent rhythmicity
Answer:
On the basis of structure, location and function, there are three types of muscles: skeletal muscle, smooth muscle and cardiac muscle.
Explanation:
Skeletal muscle:
- Most abundant type of muscle fiber
- Found attached to bones
- they are voluntary i.e they are under control of our own will.
- These muscle fibers are multinucleated
- Location: attached to bones most commonly muscles with arms, legs, body wall, face, neck.
- Has characteristic striated or striped appearance
- They soon get fatigued
Smooth muscle:
- Unstriped or non-striated muscles
- Found in the walls of hollow visceral organs
- They are involuntary i.e their function cannot be controlled by our will
- These muscles never connect with skeleton
- Muscle fibers are uninucleate
- Location: posterior parts of oesophagus, stomach, intestine, lungs, bladder, etc.
- Helps in involuntary movements such as peristalsis.
- They do not get fatigued
Cardiac muscle:
- Present in heart
- Involuntary in nature
- Composed of branched fibers
- Muscle fibers are uninucleate
- Location: in the wall of heart
- Contract and relax rapidly and rhythmically
- Never get fatigued
