Mastering Biology: Hormones and Endocrine Systems

In what ways are neurosecretory cells similar to endocrine cells? Both affect only nearby target cells. Both transmit electrical signals. Both involve split second, short lasting responses. Both release signal molecules into the bloodstream.

Both release signal molecules into the bloodstream. Endocrine cells release hormones into the bloodstream. Neurosecretory cells release neurohormones into the bloodstream.

Which of the following statements about hormones and the endocrine system is true? Hormones are produced by specialized blood cells and secreted into the blood. Hormones only affect specific cells having the appropriate receptors. Hormones are stored in the mitochondria of hormone-secreting cells. Hormones result in short-term responses as compared with nervous responses.

Hormones only affect specific cells having the appropriate receptors. Hormones convey information via the bloodstream to cells throughout the body. Cells are unresponsive to a particular signal if they lack the appropriate receptors.

Which of the following statements is true? It takes longer for hormones to be released into the bloodstream and taken to target cells than it does for electrical signals to be transmitted. Effects of hormones last for brief periods of time, while effects of electrical signals last for long periods of time. Hormones have a direct connection with target cells, while electrical signals do not. Hormones travel via specific pathways to specific cells, while electrical signals travel through the blood to all areas of the body.

It takes longer for hormones to be released into the bloodstream and taken to target cells than it does for electrical signals to be transmitted.

Body cells that respond to insulin include Liver cells only. Liver cells and muscle cells only. Muscle cells only. Intestinal cells only. Liver cells, as well as most other cells of the body.

Liver cells, as well as most other cells of the body.

What cells in the body respond to glucagon by breaking down glycogen and releasing glucose? Muscle cells. Liver cells and cells in the pancreas. Intestinal cells. Cells in the pancreas. Liver cells.

Liver cells.

From which part of the pituitary are hypothalamic hormones such as antidiuretic hormone (ADH) and oxytocin released? Posterior pituitary Neither lobe of the pituitary Both lobes of the pituitary Anterior pituitary

Posterior pituitary Hormones from the hypothalamus are released from the posterior pituitary, which does not produce its own hormones.

Which of the following statements regarding endocrine glands is true? The sex organs and the thyroid gland produce steroid hormones. Some endocrine glands, like the pituitary, have other endocrine glands as their targets. The pancreas has only nonendocrine functions. Most of the endocrine glands produce steroid hormones.

Some endocrine glands, like the pituitary, have other endocrine glands as their targets.

Which of the following is an accurate statement regarding the difference between steroid and water-soluble hormones? Steroid hormones are made from amino acids whereas water-soluble hormones are not. Steroid hormones attach to receptors in the cytoplasm; water-soluble hormones attach to receptors embedded in membranes. Steroid hormones do not directly activate genes; water-soluble hormones directly activate genes. Steroid hormones cannot pass through cell membranes; in general, water-soluble hormones can.

Steroid hormones attach to receptors in the cytoplasm; water-soluble hormones attach to receptors embedded in membranes. Steroid hormones enter the cell to take action; water-soluble hormones trigger a signal transduction pathway from outside the target cell.

A liver cell responds to insulin by Taking in glucose and converting it to glucagon. Releasing glucagon. Releasing insulin. Breaking down glycogen and releasing glucose. Taking in glucose and converting it to glycogen.

Taking in glucose and converting it to glycogen.

Antidiuretic hormone (ADH) only affects kidney cells, whereas growth hormone (GH) targets many different kinds of cells throughout the body. Which of the following is the best explanation for this observation? ADH and GH are produced by different endocrine organs. ADH is a local regulator, and GH is not. ADH is a peptide hormone, whereas GH is a protein hormone. The GH receptor is expressed in many different cells, whereas the receptor for ADH is expressed only in kidney cells.

The GH receptor is expressed in many different cells, whereas the receptor for ADH is expressed only in kidney cells. A hormone can act at any cell that expresses a receptor for that specific hormone. Growth hormone receptors are expressed by many different cells in the body. Receptors for ADH are expressed only by kidney cells.

Which of the following statements about glands and hormones is true? The anterior pituitary produces multiple hormones that affect activity of other endocrine glands and cells of the body. The pineal gland is the master control center of the endocrine system. The hypothalamus is an endocrine gland responsible for producing the hormone calcitonin. The posterior pituitary produces melatonin, which helps regulate biological rhythms.

The anterior pituitary produces multiple hormones that affect activity of other endocrine glands and cells of the body.

When blood glucose levels are low The pancreas releases insulin, which eventually causes blood glucose levels to increase. The pancreas releases insulin, which eventually causes blood glucose levels to decrease. The pancreas releases glucagon, which eventually causes blood glucose levels to decrease. The pancreas releases glucagon, which eventually causes blood glucose levels to increase. Liver cells convert more glucose to glycogen.

The pancreas releases glucagon, which eventually causes blood glucose levels to increase.

When blood glucose levels are high The pancreas releases glucose. The pancreas releases glucagon. The pancreas releases insulin. The liver releases insulin. The liver releases glucagon.

The pancreas releases insulin. The pancreas responds to high blood glucose levels by releasing insulin.

How are hormones distributed to tissues, and what determines which cells hormones will affect? They are delivered by neurosecretory cells to specific tissues and affect the cells in those tissues. They are carried to specific organs by lymphatic vessels and affect the cells in those organs. They are carried throughout the body in the bloodstream, and each hormone affects target cells that have receptors for it. They are distributed locally in the interstitial fluid and affect nearby responsive target cells.

They are carried throughout the body in the bloodstream, and each hormone affects target cells that have receptors for it.

How do hormones from the hypothalamus get to the anterior pituitary gland? They are released near a capillary bed in the hypothalamus and travel a short distance to a second capillary bed in the pituitary, where they diffuse out around the cells of the anterior pituitary. They are secreted from the neurosecretory cells in the hypothalamus directly onto the endocrine cells in the anterior pituitary. They are released near a capillary bed in the hypothalamus and travel around the body before arriving at a second capillary bed in the pituitary, where they diffuse out around the cells of the anterior pituitary.

They are released near a capillary bed in the hypothalamus and travel a short distance to a second capillary bed in the pituitary, where they diffuse out around the cells of the anterior pituitary. The releasing hormones from the hypothalamus travel a short distance from one capillary bed in the hypothalamus to a second capillary bed in the pituitary.

A characteristic of every animal hormone is that the hormone _____. acts as a regulatory message or signal between cells enters a cell and interacts with DNA is under the control of the pituitary gland is a protein

acts as a regulatory message or signal between cells Hormones are secreted into body fluids, usually blood, and communicate regulatory signals throughout the body.

Receptors for nonsteroid hormones are located in _____. the extracellular fluid the cytoplasm the nucleus the cytosol association with a cell's plasma membrane

association with a cell's plasma membrane Since nonsteroid hormones do not cross a cell's plasma membrane, their receptors are located in association with the plasma membrane.

Steroid hormones, such as the sex hormones, _____. bind to receptors in the plasma membrane are peptides, which are small molecules containing 3 to 30 amino acids can diffuse across the phospholipid membrane of cells can affect DNA directly to stimulate transcription of certain genes

can diffuse across the phospholipid membrane of cells Steroid hormones are small, nonpolar molecules that easily move across cell membranes.

An organ that produces and releases hormones is called a _________.

endocrine gland

Taken together, all of the cells of the human body that produce and secrete hormones are called the ________

endocrine system

Which of these is a nonsteroid hormone? estrogen testosterone both estrogen and testosterone oxytocin epinephrine and oxytocin

epinephrine and oxytocin Both epinephrine and oxytocin are nonsteroid hormones.

Which of these extracellular signal molecules could diffuse through a plasma membrane and bind to an intracellular receptor? estrogen epinephrine cellulose oxytocin starch

estrogen Steroid hormones such as estrogen can diffuse through the plasma membrane and bind to intracellular receptors.

People with diabetes have trouble regulating the levels of ___________in the blood. calcium glucose glucagon insulin

glucose

Compared to the endocrine system, the nervous system has a slower response and a signal that does not last as long. has a slower response with a longer-lasting signal. has a faster response, but the signal does not last as long. has a faster response with a longer-lasting signal.

has a faster response, but the signal does not last as long.

Calcitonin and parathyroid hormone are antagonistic hormones involved with calcium regulation. This antagonistic interaction means that calcitonin and parathyroid hormone _______________. have opposite effects have similar effects bind to each other when released simultaneously have unrelated effects

have opposite effects

The body's tendency to maintain relatively constant internal conditions is called homeostasis. diabetes. negative feedback. positive feedback. None of the above.

homeostasis

A ________ is a chemical substance used for communication that is produced at one site in the body and then carried in the blood to another.

hormone

When glucose levels get too high in the blood, the pancreas releases ____________, whereas when glucose levels get too low, the pancreas releases ____________. insulin; glucagon glucagon; insulin insulin; calcitonin calcitonin; glucagon

insulin; glucagon

The posterior pituitary is a component of the pituitary gland that _____. secretes the hormone prolactin (PRL), which has different effects in different species produces the endorphins, which are the body's natural painkillers is composed of nerve tissue that connects directly to the brain is composed of endocrine cells synthesizing numerous hormones

is composed of nerve tissue that connects directly to the brain It stores and secretes two hormones made in the hypothalamus.

The hypothalamus secretes a releasing hormone known as TSH-releasing hormone that _____. keeps hormones at levels that maintain homeostasis acts as the body's natural painkiller acts on blood-forming units in the bone marrow stimulates oxytocin and antidiuretic hormone

keeps hormones at levels that maintain homeostasis This system takes cues from the environment to maintain the delicate balance of systems throughout the body.

A hormone often affects only certain target cells. The reason the message of an "inappropriate" hormone is "ignored" by nontarget cells is that the nontarget cells _____. have enzymes that break down the hormone lack the genes that the hormone is attempting to activate lack receptors for the hormone produce ADH

lack receptors for the hormone Cells are unresponsive to a particular signal if they lack the appropriate receptors.

A signal molecule is also known as a(n) _____. ligand protein initiator key receptor

ligand A ligand is a signal molecule.

Which of the following is the best example of homeostasis? decreasing activity due to fatigue maintaining the pH of blood around 7.4 growing taller during development digesting food

maintaining the pH of blood around 7.4

A nerve cell that can communicate via both hormones and electrical signals is called a __________

neurosecretory cell

How do nonsteroid hormones differ from steroid hormones? nonsteroid hormones bind to a cell's DNA; steroid hormones do not bind to a cell's DNA nonsteroid hormones act via signal transduction pathways; steroid hormones do not act via signal transduction pathways the action of nonsteroid hormones never affects gene expression; the action of steroid hormones always affects gene expression nonsteroid hormones bind to cytoplasmic receptors; steroid hormones bind to plasma membrane receptors nonsteroid hormones are fat-soluble; steroid hormones are water-soluble

nonsteroid hormones act via signal transduction pathways; steroid hormones do not act via signal transduction pathways Since they do not enter the cell, nonsteroid hormones act via signal transduction pathways.

Which of the following hormones is released by neurosecretory cells extending from the hypothalamus? oxytocin estrogen calcitonin growth hormone

oxytocin

Hormones are chemicals produced by the endocrine system that are stimulated by the action of metabolic enzymes. regulate a variety of body functions, such as metabolism. function to prevent a variety of diseases, such as diabetes. control the formation of urine.

regulate a variety of body functions, such as metabolism.

The pituitary gland is important to the endocrine system because it _____. relays directives from the hypothalamus to other glands produces all of the steroid hormones connects the endocrine system with the circulatory system neutralizes the effects of endorphins

relays directives from the hypothalamus to other glands For this reason, many consider the hypothalamus to be the master component of the endocrine system.

What do these two events have in common? You respond to a hot stove by quickly pulling your hand away. You experience an increase in insulin levels after consuming soda pop. release and use of a chemical messenger common receptor molecule distance of transmission time frame of action

release and use of a chemical messenger Pulling your hand away from the stove is a response of the nervous system and requires the release of a chemical messenger (neurotransmitter). Increasing insulin levels is a response of the endocrine system and requires the release of a chemical messenger (hormone).

TRH is a type of ________ hormone secreted by the ________. releasing; hypothalamus peptide; thymus releasing; anterior pituitary steroid; thyroid gland

releasing; hypothalamus

Steroid hormones such as estrogens and androgens are produced by the __________. thymus gland sex organs two lobes of the pituitary gland pineal gland

sex organs Although many organs secrete steroid hormones, estrogens and androgens in particular are secreted by the sex organ

A signal transduction pathway is initiated when a _____ binds to a receptor. calmodulin G protein tyrosine kinase cyclic AMP signal molecule

signal molecule The binding of a signal molecule to a receptor initiates a signal transduction pathway.

In their mechanism of action, a difference between steroid and nonsteroid hormones is that _____. nonsteroid hormones bind reversibly to DNA steroid hormones enter the nucleus of the target cell, whereas nonsteroid hormones do not steroid hormones use a signal transduction pathway nonsteroid hormones cross the plasma membrane more readily than do steroid hormones

steroid hormones enter the nucleus of the target cell, whereas nonsteroid hormones do not Nonsteroid hormones typically bind to plasma membrane proteins, initiating signal transduction pathways. Steroid hormones typically enter the cell and bind with intracellular receptors. In the nucleus, the steroid hormone-receptor complex affects gene transcription.

A _______ is a cell that has receptors for a specific hormone and will therefore be affected by that hormone.

target cell

Steroid hormone-receptor complexes act in _____. the nucleus lysosomes vesicles the cytoplasm the plasma membrane

the nucleus Steroid hormone-receptor complexes bind to DNA, where they affect transcription.

The primary reason steroid hormones usually act slowly is that _____. they are produced at very low concentrations acting via a signal transduction pathway makes for slower responses than does directly interacting with a cell's DNA they are too large to enter a cell and therefore must first bind to a plasma membrane receptor before having an effect on a cell target cells tend to ignore steroid hormones in favor of nonsteroid hormones they turn genes on or off and it takes time for gene products to build up or become depleted

they turn genes on or off and it takes time for gene products to build up or become depleted This is the primary reason that steroid hormones usually act slowly.

Calcitonin is released from the _______________ and parathyroid hormone is released from the _______________. pancreas; parathyroid gland thyroid gland; pancreas thyroid gland; parathyroid gland parathyroid gland; thyroid gland

thyroid gland; parathyroid gland

Which of these is the second of the three stages of cell signaling? gene activation reception binding of a neurotransmitter to a plasma membrane receptor transduction cell response

transduction Transduction is the second of the three stages of cell signaling.

The difference between neurotransmitters and hormones has become blurred in recent years, but a chemical is currently classified as a hormone if it _____. leaves the body of the secreting organism and affects other individuals of the same species travels in the blood and has an effect on a remote tissue has its release controlled by a neuron is made in an endocrine gland

travels in the blood and has an effect on a remote tissue Chemical messengers that affect target cells convey information via the bloodstream to target cells throughout the body.