Question

11.The axial skeleton:

A.protects and supports internal organs.

B.participates in vital functions such as respiration.

C. includes the scapulae

D.provides attachment sites for skeletal muscles and therefor movement.

E. includes the bones of the auditory ossicles of the middle ear.

12. Which generalization concerning movement by skeletal muscles would be true?

A. A muscle’s origin is usually proximal to the part which it moves.

B. Muscles produce movements both by pulling and pushing on bones.

C. The insertion usually moves toward the origin.

D. Flexors are typically stronger than extensors.

E. The tendon attachment to the more stationary end of the bone is the origin.

13. Sarin gas is an organophosphorus compound that attacks the nervous system by

preventing the breakdown of acetylcholine (acetylcholineasterase is blocked). This would mean that:

A. the neurotransmitter would continue to act on the muscle fiber.

B. there would be loss of voluntary control of skeletal muscle.

C.the individual would experience spastic paralysis and uncontrolled muscle contraction.

D. this gas can be fatal due to respiratory muscles not being able to relax

E. the muscles would not be able to contract because no ACh would reach the membrane.

14. Anaerobic muscular activity:

A. enables the cells to generate ATP when mitochondria are unable to meet the energy demands.

B. Uses carbohydrates in the glycolytic process.

C. produces lactic acid when pyruvic acid builds up faster than the mitochondria can utilize it.

D. can only continue so long as mitochondrial activities continue

E. is influenced by the oxygen provided by the blood.

Answer 1

11. A.protects and supports internal organs

Explanation: The most important function of axial skeleton is to protect the organs prsent in the central part of the body such as brain, heart, lung etc.

12. C. The insertion usually moves toward the origin.

Explanation: origin is the stationary point while insertion is the mobile point that moves towards the origin.

13. C.the individual would experience spastic paralysis and uncontrolled muscle contraction.

Explanation: Due to inhibition of Acetylcholine esterase enzyme,Acetylcholine is unable to get broken down leading to its prolonged action on the muscle fiber. this causes prolonged contraction of the skeletal muscle causig spastic paralysis

14. C. produces lactic acid when pyruvic acid builds up faster than the mitochondria can utilize it.