In a positive-feedback system where hormone A alters the amount of protein X
A) an increase in A always produces an increase in X.
B) an increase in X always produces a decrease in A.
C) a decrease in A always produces an increase in X.
D) a decrease in X always causes a decrease in A.
E) it is impossible to predict how A and X affect each other.
Answer: A
Learn More :
Biology
- Endocrine structures derived from nervous tissue include the
- Oxytocin and antidiuretic hormone are synthesized in the
- In a lactating mammal, the two hormones that promote milk synthesis and milk release, respectively, are
- To prevent insect pests from maturing into reproducing adults, pest controllers use synthetic agonists of
- A product of the anterior pituitary gland that causes color changes in its target cells is
- Prolactin stimulates mammary gland growth and development in mammals and regulates salt and water balance in freshwater fish. Many scientists think that this wide range of functions indicates that prolactin
- The hypothalamus
- If a person loses a large amount of water in a short period of time, he or she may die from dehydration. ADH can help reduce water loss through its interaction with its target cells in the
- Portal blood vessels connect two capillary beds found in the
- The hypothalamus modulates hormone secretion by the anterior pituitary by means of
- The interrelationships between the endocrine and the nervous systems are especially apparent in
- Based on their effects, which pair below would not be expected to be active at the same time and place?
- During short-term starvation, most available fuel molecules are catabolized to provide energy for metabolism rather than being used as building blocks for growth and repair, a trade-off that is hormonally regulated by
- During mammalian labor and delivery, the contraction of uterine muscles is enhanced by oxytocin. This is an example of
- Hormones that promote homeostasis
- Suppose that substance X is secreted by one cell, travels via interstitial fluid to a neighboring cell, and produces an effect on that cell. All of the following terms could describe this substance except
- Nitric oxide and epinephrine
- For hormones that homeostatically regulate cellular functions,
- When a steroid hormone and a peptide hormone exert similar effects on a population of target cells, then
- Hormone X activates the cAMP second messenger system in its target cells. The greatest response by a cell would come from
- A chemical signal operating in a paracrine manner is one that
- Endocrine glands that are sources of steroid hormones
- Insect hormones and their receptors
- Different body cells can respond differently to the same peptide hormones because
- The reason that the steroid hormone aldosterone affects only a small number of cells in the body is that
If the answers is incorrect or not given, you can answer the above question in the comment box. If the answers is incorrect or not given, you can answer the above question in the comment box.