Secretions that affect only nearby cells are termed:
Autocrine.
Endocrine.
Exocrine.
Paracrine.
The Correct Answer is D
Paracrine secretions are chemical signals that affect only nearby cells.
They are released by the sending cell and diffuse through the extracellular space to the target cell, which has a specific receptor for the signal.
Paracrine signaling is a form of local signaling that occurs in multicellular organisms.
Choice A is wrong because autocrine secretions are chemical signals that act on the same cell that produced them.
Autocrine signaling is also a form of local signaling, but it involves cell signaling itself.
Choice B is wrong because endocrine secretions are chemical signals that are secreted into the blood and act at long distances.
Endocrine signaling is a form of long-range signaling that involves ductless glands that secrete hormones.
Choice C is wrong because exocrine secretions are non-hormonal substances that are secreted into ducts to the external environment.
Exocrine signaling is not a form of cell-cell communication, but rather a way of releasing substances such as sweat, saliva, or digestive enzymes.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is A
Explanation
The celiac artery supplies blood to the liver, spleen, and stomach.
It is one of the three major branches of the abdominal aorta, along with the superior mesenteric artery and the inferior mesenteric artery.
The celiac artery divides into three branches: the left gastric artery, the splenic artery, and the common hepatic artery.
Choice B is wrong because the brachiocephalic artery is a large vessel that arises from the aortic arch and supplies blood to the right side of the head and neck and the right arm.
It has no connection to the liver or spleen.
Choice C is wrong because the renal arteries are paired vessels that arise from the abdominal aorta and supply blood to the kidneys.
They are located below the superior mesenteric artery and above the inferior mesenteric artery.
Choice D is wrong because the tibial arteries are branches of the popliteal artery that supply blood to the lower leg and foot.
They are located in the posterior and anterior compartments of the leg.
The normal range of blood pressure in the celiac artery is about 100-120 mmHg systolic and 60-80 mmHg diastolic.
The normal range of blood flow in the celiac artery is about 200-300 ml/min. The normal diameter of the celiac artery is about 5-7 mm.
Correct Answer is C
Explanation
Uterine contractions during childbirth illustrate a positive feedback mechanism.
A positive feedback mechanism is a process in which the end products of an action cause more of that action to occur in a feedback loop.
This amplifies the original action.
For example, when a woman goes into labor, the pressure of the baby’s head on the cervix stimulates nerve impulses that travel to the brain and trigger the release of oxytocin, a hormone that causes the uterus to contract.
The contractions increase the pressure on the cervix, which stimulates more nerve impulses, more oxytocin, and more contractions.
This cycle continues until the baby is delivered.
Choice A is wrong because body temperature control is an example of a negative feedback mechanism, which is when the end results of an action inhibit that action from continuing to occur.
For example, when the body temperature rises above normal, the skin sweats, and blood vessels dilate to release heat.
This lowers the body temperature back to normal and stops sweating and dilation.
Choice B is wrong because control of blood sugar is also an example of a negative feedback mechanism.
For example, when the blood sugar level rises after a meal, the pancreas secretes insulin, a hormone that helps cells take up glucose from the blood.
This lowers the blood sugar level back to normal and stops the insulin secretion.
Choice D is wrong because maintaining blood pressure is another example of a negative feedback mechanism.
For example, when the blood pressure drops due to blood loss or dehydration, the heart beats faster and stronger, and the blood vessels constrict to increase the blood pressure.
This restores the blood pressure back to normal and stops the heart rate and vessel constriction.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today