Question

The ultrastructure of a muscle contains many micro units are called as ___________

• A. Microfibrils
• B. Macrofibrils
• C. Myofibrils
• D. Mesofibrils

Answer 1

The correct option is C

Myofibrils

Collagen, in the form of elongated fibrils, is mostly found in fibrous tissues such as tendons, ligaments and skin. It is also abundant in corneas, cartilage, bones, blood vessels, the gut, intervertebral discs and the dentin in teeth. Each individual fiber of collagen is made up of many small fibers, called macrofibrils, all bound together. And all of the macrofibrils are themselves made up of even tinier fibers called microfibrils. This structure accounts for the strong nature of collagen.
A myofibril (also known as a muscle fibril) is a basic rod-like unit of a muscle cell. Muscles are composed of tubular cells called myocytes, known as muscle fibers in striated muscle, and these cells in turn contain many chains of myofibrils.
Neurons are the basic units of the nervous system and its most important part is the brain