Test 3-II. - PRINTABLE VERSION Test 3 You scored 78 out of...

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

View Full Document Right Arrow Icon
PRINTABLE VERSION Test 3 You scored 78 out of 100 Question 1 Your answer is INCORRECT. In twitch summation: a) The muscle fiber is stimulated again before the action potential has returned to resting potential. b) The muscle fiber is stimulated again before the filaments have completely returned to their resting position. c) Stronger muscle contractions occur but stronger action potentials do not occur. d) Both [b] and [c] above e) All of these answers Question 2 Your answer is INCORRECT. Which of the following statements regarding skeletal muscle is true: a) Calcium in muscles cells is required for cross-bridges between actin and myosin. b) ATP binds troponin allowing the myosin-binding site on actin to be made available. c) ATP is stored in the sarcoplasmic reticulum. d) Skeletal muscles lack mitochondria e) All of these Question 3 Your answer is CORRECT. With eccentric muscle contractions: a) The development of tension occurs at constant muscle length. b) The muscle lengthens while contracting. c) The muscle shortens while contracting. d) Muscle length and tension vary throughout a range of motion. e) None of these answers. Question 4 Your answer is CORRECT. A motor unit refers to: a) a single motor neuron plus all of the muscle fibers it innervates. b) a single muscle fiber plus all of the motor neurons that innervate it. c) all of the motor neurons supplying a single muscle. d) a pair of antagonistic muscles. e) a sheet of smooth muscle cells connected by gap junctions. Question 5 Your answer is INCORRECT. Calcium that enters the cell during smooth muscle excitation binds with: a) calmodulin.
Background image of page 1

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

View Full DocumentRight Arrow Icon
inactive myosin kinase. c) troponin. d) myosin. e) actin. Question 6 Your answer is INCORRECT. According to the sliding filament mechanism of muscle contraction, the thin filaments slide towards the M line to shorten the sarcomere. a) True b) False Question 7 Your answer is INCORRECT. Blood returning from the lungs: a) enters the right atrium. b) enters the left atrium c) is poorly oxygenated. d) both [a] and [c] above e) both [b] and [c] above Question 8 Your answer is CORRECT. The plateau of the cardiac action potential results from the opening of voltage-gated slow _____ channels in the plasma membrane of the cardiac cell. a) sodium b) potassium c) calcium d) chloride e) magnesium Question 9 Your answer is CORRECT. Which of the following ECG waves represents ventricular depolarization? a) P wave b) QRS complex c) T wave d) PR segment e) ventricular depolarization occurs simultaneously with atrial repolarization and can not be recorded. Question 10 Your answer is CORRECT. Which of the following conditions does not exist during the TP interval? a) Atrial pressure is greater than ventricular pressure. b)
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.

Page1 / 9

Test 3-II. - PRINTABLE VERSION Test 3 You scored 78 out of...

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