A sarcomere is the
A. contractile thread that extends the length of the muscle fiber.
B. plasma membrane of a muscle fiber.
C. protein strand composed of actin or myosin.
D. structural and functional unit of the skeletal muscle fiber.
E. cytoplasm of a muscle fiber.
Answer: D
You might also like to view...
Which of the following is true of potassium ions?
a. they are actively secreted in the proximal tubule b. their concentration is controlled by aldosterone c. changes in concentration can affect membrane excitability d. are reabsorbed in the distal tubule e. both (b) and (c)
Match each substance with its primary mode of transport across the kidney epithelium.
1. sodium 2. glucose 3. urea 4. small plasma proteins A. transcytosis B. active transport C. symport with a cation D. passive reabsorption/diffusion
If there is an increase in systemic blood pressure, the resulting stretch of afferent arterioles results in reflexive
A. vasodilation of afferent arterioles to keep GFR normal. B. vasodilation of efferent arterioles to lower GFR. C. vasoconstriction of afferent arterioles to keep GFR normal. D. vasoconstriction of efferent arterioles to raise GFR.
Where are color, object movement, and depth processed?
A) precentral gyrus B) auditory association cortex C) visual association areas D) premotor cortex