Since the action potential "leaps" from node to node in a myelinated axon, ________.
A. action potentials move faster if the nodes are farther apart
B. Na+ movement within the myelin sheath is possible
C. Na+ channels are not present between the nodes
D. myelinated axons need far less Na+ channels than unmyelinated axons
Answer: C
You might also like to view...
Disaccharides are one type of
A. carbohydrate. B. starch. C. lipid. D. essential amino acid. E. triglyceride.
You pick up the skull and begin examining it. The mastoid process is rather small, and the external occipital protuberance is not well defined. The supraorbital margins are rather sharp, and the mental protuberance is pointed (instead of squared-off). All of these features lead you to the following conclusion: The skull is from a female. Based on the answer you gave to question 3, what feature(s) would you expect to see in the pelvis?
a. narrow pelvic inlet b. elongated, rectangular pubic bones c. narrow, U-shaped sciatic notch d. 90-degree subpubic arch
The round ligament is the remnant of the fetal ductus venosus.
Answer the following statement true (T) or false (F)
Which of the joints shown in the figure only permits back-and-forth and side-to-side movements between the articulating bones?
a) A b) B c) C d) Both A and B e) Both A and C