Week 2 Introductory Myology / Muscle Tissue; Muscles of the Shoulder Region

Question 1

What type of muscle contraction is required of the triceps brachii from A to B if moving very slowly?

Answer 1

Essentric contraction. The elbow extensors must control the arm from falling quickly (flexion of the elbow) as a result of gravity acting on the arm.

Question 2

What form of muscle is the one in the picture?

Answer 2

Strap

Question 3

Muscle X and muscle Y are of equal size. The form of muscle X is parallel and quadrilateral, while the form of muscle Y is oblique and multipennate. Which of the following functions is muscle X better adapted to perform compared with muscle Y?

Answer 3

Large range joint movement. All the muscle cells in parrallel muscle are in the line of pull of the muscle. This results in maximum shortening of the muscle during contraction.

Question 4

What type of muscle contraction is required off the elbow flexors from figure A to B if moving very slowly?

Answer 4

No contraction. Any contraction of the elbow flexors with the upper limb in this position would cause the arm to drop towards the head quickly as ggravity is exerting a force on the arm.

Question 5

At what range is the triceps brachii muscle contraction from in figure B to A?

Answer 5

Outer to mid range.