How is vitamin D (vitamin D3) related to calcium homeostasis in bone?
A) Vitamin D provides a framework for calcium in the matrix.
B) Vitamin D is regulated by osteoclast activity.
C) Vitamin D is produced by osteoblasts during endochondral ossification.
D) Vitamin D is involved in calcium absorption by the digestive tract.
E) Vitamin D replaces calcium in the skeleton.
Which structure is lined by a ciliated epithelium?
A) 1
B) 2
C) 9
D) 11
E) 12
A hormone might
A) alter a membrane channel by changing its shape, thereby affecting what can go
through it.
B) depolarize a skeletal muscle cell.
C) interfere with norepinephrine at a neuronal synapse.
D) inactivate glucose so it cannot be used by a cell.
E) block the production of a cell membrane.