Exam 47: Chemical Signals in Animals

In experiments where researchers suspect that a hormone may be responsible for a certain physiological effect,they may cut the neurons leading to the organ where the effect being studied occurs.What is the purpose of cutting these neurons?

Which of these glands is located within the abdominal cavity?

In human embryonic development,which of the following pairs of hormones are released by the developing testes and result in development of the male reproductive tract and inhibition of the female reproductive tract?

Tadpoles must undergo a major metamorphosis to become frogs.This change includes reabsorption of the tail,growth of limbs,calcification of the skeleton,increase in rhodopsin in the eye,development of lungs,change in hemoglobin structure,and reformation of the gut from the long gut of an herbivore to the short gut of a carnivore.Amazingly,all of these changes are induced by thyroxine.What is the most likely explanation for such a wide array of effects of thyroxine?

All of the following are examples of amplification of a hormone signal except _____.

Which of the following is true during a typical cAMP-type signal transduction event?

If a portion of the pancreas is surgically removed from a rat and the rat subsequently loses its appetite,one explanation is that the removed portion contains cells that secrete a chemical signal that somehow stimulates appetite.Given this scenario,what type of chemical signaling is occurring?

Of the following types of molecules,which can function as both neurotransmitters and hormones?

A cluster of tumor cells that produces and secretes growth factors to induce surrounding cells to grow and divide are showing which type of cell-to-cell signaling?

When adenylyl cyclase is activated ________.

When partially digested food enters the small intestine from the stomach,several events must occur to protect the intestine and allow for the continued digestion of the food.One hormone in particular performs two of these functions.What intestinal hormone is responsible for causing the pancreas to release digestive enzymes and the gallbladder to release bile salts into the intestine?

Prolactin tumors can cause a number of effects on the body.Which of the following might occur in a male patient?

What is the only type of chemical signal that is not intended to alter the physiology of the animal producing that signal?