Why is back pain so common in humans?

When curare, a neuromuscular poison, is dropped onto an isolated muscle-nerve preparation in a laboratory, the muscle does not contract when the nerve is stimulated, even though neurotransmitter is released from the nerve cell. Why does this happen? How might this action of curare be lethal to an individual who has been poisoned?

How does asynchronous flight muscle differ from that of synchronous? Which is capable of faster wing-beat frequency and why?

A patient with heart disease experiences pain at the base of the neck and in the left shoulder and upper limb during exercise. How would you explain the likely origin of this pain to the patient? HINT How does referred pain happen?

The disease poliomyelitis (po′le-o-mi′˘e-li′tis) destroys motor neurons, causingloss of muscle function and even flaccid paralysis. Some patients recoverbecause axon branches form from the remaining motor neurons. Thesebranches innervate the paralyzed muscle fibers to produce motor unitswith many more muscle fibers than usual. How does this reinnervation ofmuscle fibers affect the degree of muscle control in a person who hasrecovered from poliomyelitis?

Bruxism is a condition in which individuals clench and/or grind their teeth. It often occurs as they sleep, leading to jaw pain and damaged teeth. Which muscles contract during this nocturnal event? What are possible causes of bruxism?

The term somatic cell refers to: A) normal body cells other than sperm and egg B) pluripotent cells C) most stem cells D) all of the above are somatic cells

What do you mean by alary muscles?

IV. Complete these sentences using the terms anterior or posterior. (23) The scapula is (24) The maxillary central incisors are (25) The radial nerve in the brachial area is (26) The occipital lobe is to the heart. to the maxillary molars. to the upper portion of the humerus. to the frontal lobe of the human brain. V. Complete these sentences using the terms lateral or medial. (27) The arms are, (28) The vertebral column is (29) The nose is (30) The fifth digits of the feet are_ to the nipples. _to the scapula. to the eyes. to the first digits. VI. Complete these sentences using proximal or distal. (31) The palms are (32) The axilla is (33) The toes are (34) The knees are the elbow. to the first digit. to the knees. to the groin.

What do you mean by voluntary muscles?