Which of the following statements about rods and cones in the retina is TRUE?
A. Rods provide higher visual acuity than do cones.
B. Cones are found in highest density in the fovea; rods are more prevalent near the edges of the retina.
C. Rods require brighter light to activate them than do cones.
D. Rods and cones all have the same kind of opsin.
E. Cones enable us to see in dim light; rods provide color vision.
Answer: B
You might also like to view...
If the human carpometacarpal thumb joint were a uniaxial hinge joint instead of a saddle joint...
a) the thumb would exhibit rotational movement. b) the ability to grasp and hold objects would be hindered. c) then sliding and twisting motions would become prominent. d) it would allow for abduction and adduction but not flexion and extension.
Which of the following changes have the potential to dramatically affect the potential difference across the plasma membrane?
A. increased permeability of the membrane to sodium ions B. increased intracellular concentration of potassium ions C. any change in the rate at which the sodium-potassium pump works D. increased permeability of the membrane to sodium ions and increased intracellular concentration of potassium ions E. increased permeability of the membrane to sodium ions, increased intracellular concentration of potassium ions and any change in the rate at which the sodium-potassium pump works
The postganglionic parasympathetic fibers that are controlled by pelvic splanchnic nerves innervate thea: Large intestineb: Reproductive organsc: Salivary glandsd: Pupillary constrictor musclese: Urinary bladderf: Ureters
A. b, c, e B. a, d, e C. a, c D. a, b, e, f E. c, d, f
When the level of potassium ions in the ECF increases,
A) osmoreceptors swell. B) ions are conserved. C) less ADH is released. D) there is an increase in the level of aldosterone. E) there is a decrease in the level of atrial natriuretic peptide.