Exam4 416K-Fall 06

Exam4 416K-Fall 06 - Name_ Bio416K Physiology and...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Name________________________________ Bio416K Physiology and Functional Anatomy I Lecture Exam 4 Fall 06 1. The sarcoplasmic reticulum has the following role in skeletal muscle contraction: a. Conduction of the action potential stimulated by the end plate potential b. Contains the dihydropyridine receptor proteins that translate the sarcolemma action potential c. Regulates Na + and K + levels in the sarcoplasm to reduce muscle fatigue d. Supplies glycogen and fatty acids for ATP production in the sarcoplasm e. Releases calcium in response to the sarcolemma action potential to initiate contraction 2. Manganese ions block the calcium channels in the cell membrane of contractile cardiac muscle cells. How would the presence of manganese in the extracellular fluid affect the contraction of the heart muscle? a. The plateau phase of contraction would be longer b. The action potential refractory period would be longer c. The heart would contract less forcefully d. The heart rate would increase e. The contraction phase would be prolonged 3. While watching Olympic weight lifters on the television, you notice that on several occasions an athlete would lift the weight to his chest and then suddenly drop it as if the muscles lifting the weight involuntarily relaxed. Which reflex would most likely explain what was happening to the weight lifter? a. Muscle spindle reflex b. Crossed extensor reflex c. Golgi tendon organ reflex d. Reciprocal inhibition reflex e. Kinesthetic joint receptor reflex 4. Which of the following would be affected if the number (availability) of muscle nicotinic acetylcholine receptors were reduced (for example, as occurs in the disease myasthenia gravis)? a. Muscle end plate potential b. Somatic motor neuron action potential frequency c. Somatic motor neuron acetylcholine release d. Muscle cell resting membrane potential e. Somatic motor neuron acetylcholinesterase activity 5. In skeletal muscle myofibrils, at the end of the power stroke, ______________. a. Inorganic phosphate has been released from the myosin b. Actin has been moved toward the M line c. The myosin head releases ADP and resumes the rigor state d. The myosin head is tightly bound to actin e. All of these are correct 1
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
6. The nervous system controls motor movements through a hierarchy of three successive levels – 1) the precommand level, 2) the initiation level, and 3) the execution level. Which of the following brain areas sends efferent nerve fibers
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 03/19/2008 for the course BIO 416K taught by Professor Findell during the Fall '08 term at University of Texas.

Page1 / 6

Exam4 416K-Fall 06 - Name_ Bio416K Physiology and...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online