Question

Red muscle fibres are rich in
A. Golgi body
B. Mitochondria
C. Lysosomes
D. Ribosomes

Answer 1

Hint: Muscle fibre contains hemoprotein myoglobin which makes it red. Myoglobin is a protein that can bind iron to the oxygen. Organism like a whale comprises a high amount of myoglobin which allows it to hold the breath for a larger period. During aerobic oxidation, Red muscle fibre does not accumulate lactic acid that allows the fibre to contract slowly for long.

Complete answer:
-The Golgi body is a membrane-bound organelle which is found in most of the eukaryotes. The Golgi body comprises a set of glycosylation enzymes.
-The main function of the Golgi body is the processing of protein and lipid into a membrane-bound vesicle.
-Mitochondria are double membraned organelles. The major functions of mitochondria are ATP production, cell signalling, cell death etc.
-Red muscle fibre contains a high number of mitochondria and less number of sarcoplasmic reticulum.
-The high concentration of mitochondria synthesizes a larger amount of ATP which allows the muscle fibre to contract for longer`.
-A Lysosome is a spherical vesicle that possesses hydrolytic enzymes. Hydrolytic enzymes are responsible for breaking down various biomolecules.
-Ribosomes are composed of ribonucleoprotein.
-IT comprises two subunits, larger catalytic subunit and smaller decoding subunit. It is responsible for the synthesis of protein by connecting the amino acids.
So, the correct answer is “Option B”.

Note:
Red muscle fibre is also called slow-twitch fibres. Myoglobin of red muscle fibre transports the oxygen to the interior for ATP production. The Red muscle fibre is mainly responsible for maintaining body posture, sitting, standing, locomotion etc. In comparison to red muscle fibres, white muscle fibres comprise less mitochondria, myoglobin and capillaries. White muscle fibres are the fast-twitch fibres that involve well developed sarcoplasmic reticulum.