The beak of birds is covered by a sheath of overlapping keratin scales called the
A) Rhamphotheca.
B) Rostrum.
C) Osculum.
D) Manubrium.
Answer: A
You might also like to view...
Which endocrine gland also performs exocrine functions?
A) thymus B) pituitary gland C) thyroid gland D) pancreas
In the ovarian cycle, the dominant follicle:
A. undergoes atresia. B. continues to grow beyond day 7 of the cycle, while the other developing follicles degenerate. C. is selected on day 1 of the cycle, and no other follicles develop beyond that day. D. is selected to continue growing at about the middle of the luteal phase. E. ruptures during ovulation on day 21 of the cycle.
Which curves of the vertebral column are present at birth?
A. Cervical and thoracic B. Lumbar and thoracic C. Thoracic and sacral D. Lumbar and sacral E. Lumbar and cervical
Contraction of the atria of the heart leads to blood moving directly
a) into auricles. b) into arteries. c) into veins d) through atrioventricular valves e) through semilunar valves.