A protein is found in blood that is produced by the pancreas and acts on receptors of cells in the liver. What type of physiological regulator is it most likely to be?
A. An autocrine signal
B. A neurotransmitter
C. An enzyme
D. A hormone
E. A paracrine signal
Answer: D
You might also like to view...
Mitral valve prolapse causes blood to leak back into the ________ when the ventricles contract.
A. pulmonary trunk B. right atrium C. left atrium D. pulmonary arteries E. aorta
Which abundant antibody is the only one to cross the placental barrier?
A) IgA B) IgM C) IgD D) IgG E) IgE
Answer the following questions true (T) or false (F)
1. Vesicles known as melanosomes are taken into the cytosol of keratinocytes by endocytosis. The melanosome is transported to the superficial side of the keratinocyte to shield its nucleus. 2. Carotene and hemoglobin are two pigments that contribute to skin color in minor ways. 3. Hairs grow from cells in the matrix of the root that are still undergoing keratinization.
Nephrons located close to the medulla with long nephron loops are called
A) calyces. B) columnar nephrons. C) cortical nephrons. D) perimedullary nephrons. E) juxtamedullary nephrons.