Muscle Biology

The deltoid muscle, specifically the middle fibers, is primarily responsible for abducting the arm sideways (raising it away from the body in the coronal plane). This large, triangular muscle covers the shoulder joint and is the main abductor of the arm beyond 15 degrees. The other options are incorrect: bronchus is an airway tube, flexor pollicis moves the thumb, biceps flexes the elbow.

The tongue is often cited as the strongest muscle relative to its size and for its endurance (constantly active for eating/speaking/swallowing). However, the masseter (jaw muscle) exerts more absolute force, and gluteus maximus is largest. This is a commonly oversimplified trivia fact.

MI stands for Myocardial Infarction, the medical term for heart attack. 'Myocardial' refers to the heart muscle (myocardium), and 'Infarction' means tissue death due to lack of blood supply. Note: the correct spelling is 'Infarction' not 'Infraction'.

The tongue is attached at both ends - to the hyoid bone and the mandible (lower jaw). Additionally, other muscles in the body are also attached at only one end, such as some facial muscles. The statement is factually incorrect on both counts.

While the tongue is often cited as the strongest muscle based on its size-to-strength ratio and constant use, this is actually a common misconception. The masseter (jaw muscle) exerts the most pressure. However, among the given options, the tongue is the conventional answer expected.

The gluteus maximus is indeed the largest muscle in the human body by volume. It's the main extensor muscle of the hip and the muscle we sit on.

The tongue is often cited as the strongest muscle in the body relative to its size. It's composed of multiple muscle groups that work together constantly for speaking, swallowing, and chewing. While the masseter (jaw muscle) can exert more absolute force, the tongue has exceptional endurance and is always working.

Yes, it is correct. Smooth muscles cells are present in uterus.

Cells are cylindrical and unbranched.

This is the correct option. Heavy weightlifters develop muscle cramps after heavy exercise. This is due to the accumulation of lactic acid in the muscles.

Myoglobin is an iron- and oxygen-binding protein found in the muscle tissue of vertebrates in general and in almost all mammals. It is related to hemoglobin, which is the iron- and oxygen-binding protein in blood, specifically in the red blood cells.

  Skeletal muscle is unable to undergo a sustained contraction.