During concentric isotonic contraction of a skeletal muscle fiber, which of these occurs?
A. Thin filaments shorten
B. Sarcomeres lengthen
C. A bands lengthen
D. I bands shorten
E. A bands shorten
Answer: D
You might also like to view...
Which of the following enzymes in an RBC breaks H2CO3 down to water and carbon dioxide?
A) Hemoglobinase B) Carboxyhemoglobinase C) Carbonic anhydrase D) Carbaminoreductase E) Bisphosphoglycerase
The C cells of the thyroid gland produce
A) thyroxine. B) TSH. C) calcitonin. D) PTH. E) triiodothyronine.
Choose the correct statement regarding neonates.
A) Urinary water losses are low. B) The digestive system is extremely active before birth. C) Neonatal respiratory rates are considerably lower than those of adults. D) Typical neonatal heart rates are lower than fetal heart rates. E) At birth, the lungs are fully expanded and filled with fluid.
In the light-adapted state,
A) photoreceptors are much more sensitive to stimulation. B) photoreceptors are much less sensitive to stimulation. C) we can only see color, and not black and white. D) we would see better in the dark. E) colors are dull.