A&P II Self Midterm

What is the mechanism of action of lipid-soluble hormones? A) Activation of genes, which increase protein synthesis in the cell. B) Phosphorylation of intercellular proteins. C) Increasing protein kinases.

A) Activation of genes, which increase protein synthesis in the cell.

Intracellular signaling pathways within target cells are organized such that: A) Each step allows for amplification of the signal where one molecule can activate many. B) Enzymes are used up and degraded after each individual reaction they catalyze. C) Each step involves one molecule activating or synthesizing exactly one other molecule for precise control.

A) Each step allows for amplification of the signal where one molecule can activate many.

Steroid hormones exert their action by ___________. A) Entering the nucleus of a cell and initiation or altering the expression of a gene. B) Binding cell receptors and initiating cAMP activity. C) Activating the hypothalamic release of regulating hormones.

A) Entering the nucleus of a cell and initiation or altering the expression of a gene.

Which of the following is NOT a category of endocrine gland stimulus? A) Enzymes B) Humoral C) Neural regulation D) Hormonal

A) Enzymes

Acromegaly and gigantism are the result of ___________ of growth hormones. A) Hypersecretion B) Hyposecretion C) Normal production

A) Hypersecretion

Which of the following is true of epinephrine? A) It is a tyrosine amine hormone. B) It is a tryptophan amine hormone. C) It is a proline amine hormone. D) It is a serine amine hormone.

A) It is a tyrosine amine hormone.

Concerning the half-life of hormones: A) Lipid-soluble hormones generally have a longer half-life. B) Hormones with a shorted half-life regulate activities with a slow onset and long duration. C) Hormones with a shorted half-life are maintained at more constant levels in the blood.

A) Lipid-soluble hormones generally have a longer half-life.

Which of the following are functions of the endocrine system (select all that apply): A) Maintenance of water, electrolyte and nutrient balance. B) Reproduction. C) Regulation of cellular metabolism and energy balance. D) Integration of sensory information. E) Development and influence of behavior and emotions. F) Immune system response. G) Growth and development.

A) Maintenance of water, electrolyte and nutrient balance. B) Reproduction. C) Regulation of cellular metabolism and energy balance. E) Development and influence of behavior and emotions. F) Immune system response. G) Growth and development.

As someone starts to develop in puberty, most cells in their reproductive organs are probably starting to express: A) More receptors for sex hormones. B) Fewer receptors for sex hormones.

A) More receptors for sex hormones.

When a chemical messenger helps initiate an inflammatory response by causing cellular changes in neighboring cells, it is demonstrating _______________ signaling. A) Paracrine B) Allomone C) Autocrine D) Pheromone

A) Paracrine

Within the adenylate cyclase signal transduction pathways of target cells, cAMP activates: A) Protein kinase B) The G protein C) The receptor D) Transcription of mRNA

A) Protein kinase

The hypothalamus: A) Rests in the sell turcica B) Is also called the neurohypophysis C) Is located inferior to the pituitary gland D) Is located superior to the thalamus

A) Rests in the sell turcica

Endocrine glands _____________. A) Secrete chemical messengers that travel in the bloodstream. C) Include sebaceous glands and sweat glands. C) Secrete hormones that travel through a duct to the target organs. D) Release neurotransmitters into the synaptic cleft.

A) Secrete chemical messengers that travel in the bloodstream.

Endocrine glands (select all that apply): A) Secrete hormones directly into the bloodstream. B) Are the organs of the endocrine systems. C) Help to maintain homeostasis. D) Have ducts.

A) Secrete hormones directly into the bloodstream. B) Are the organs of the endocrine systems. C) Help to maintain homeostasis.

Which hormones are synthesized from cholesterol? A) Steroids B) Modified amino acids C) Peptides D) Glycoproteins E) All of the above

A) Steroids

When the effects of water-soluble hormones on their target cells are considered, the hormone itself is: A) The first messenger B) The phospholipase C) The third messenger D) The second messenger E) The hormone-response element

A) The first messenger

All adenohypophyseal hormones except growth hormones (GH) affect their target cells via cyclic AMP (cAMP) second messenger. A) True B) False

A) True

All peptide hormone synthesis requires gene activation that produces mRNA. A) True B) False

A) True

Among their many functions, hormones regulate blood volume, cellular concentration, and the number of platelets. A) True B) False

A) True

Both "turn on" factors (hormonal, humoral, and neural stimuli) and "turn off" factors (feedback inhibition and others) may be modulated by the activity of the nervous system. A) True B) False

A) True

Hormone secretion is primarily regulated by negative feedback. A) True B) False

A) True

Neurotransmitters are a special class of paracrines. A) True B) False

A) True

All peptide hormone synthesis requires gene activation that produces mRNA. A) Water-soluble hormones such as insulin and epinephrine. D) Lipid-soluble hormones such as thyroid hormones and cortisol.

A) Water-soluble hormones such as insulin and epinephrine.

What type of hormones bind to receptors located on the cell membrane? A) Water-soluble hormones such as insulin and epinephrine. B) Lipid-soluble hormones such as thyroid hormones and cortisol.

A) Water-soluble hormones such as insulin and epinephrine.

The term down-regulation refers to the process by which: A) A carrier protein increases the rate of degradation for a hormones and thereby decreases its blood concentration. B) A cell decreases the number of receptors it has for a hormone. C)A large amount of hormone shunts down all metabolic activity in a target cell. D) A carrier protein decreases the rate of degradation of the protein it ferries. E) A glandular cell decreases the amount of hormone it secretes.

B) A cell decreases the number of receptors it has for a hormone.

Too much GH in a fully grown adult results in: A) Giantism B) Acromegaly C) Simmond's disease D) Diabetes insipidus

B) Acromegaly

Which is the correct order of events for hormones activating Gs proteins? A) Activation of a G protein, tyrosine kinase receptor, phosphorylation of intracellular proteins. B) Activation of G protein, binding of GTP, activation of adenylyl cyclase, conversion of ATP to cAMP. C) Activation of G protein, binding of GTP, activation of phospholipase C, activation of DAG and IP3.

B) Activation of G protein, binding of GTP, activation of adenylyl cyclase, conversion of ATP to cAMP.

What type of response is initiated by steroid and thyroid hormones? A) Makes more hormones B) Alters activity of genes C) Provide feedback D) Produce enzymes

B) Alters activity of genes

Which of the following hormones has intracellular receptors? A) Epinephrine B) Cortisol C) Insulin

B) Cortisol

What BEST describes the process of up-regulation? A) Decrease the number of surface receptors. B) Decrease the amount of hormone. Increase the number of surface receptors. C) Decrease desensitization from prolonged exposure to increase hormone. D) All of the above.

B) Decrease the amount of hormone. Increase the number of surface receptors.

Hormones often cause a cell to elicit multiple responses; this is because _____________. A) The receptors bind to several hormones at the same time. B) During protein kinase activation, enzymes phosphorylate many other enzymes. C) There are thousands of receptors on the cell membrane. D) The protein kinases are rapidly metabolized into functional amino acids.

B) During protein kinase activation, enzymes phosphorylate many other enzymes.

Cells of the posterior pituitary produce antidiuretic hormone (or vasopressin). A) True B) False

B) False

Which of the following will inhibit the secretion the secretion of growth hormone? A) Growth hormone-releasing hormone (GHRH) B) Growth hormone-inhibiting hormone (GHIH) C) IGFs (somatomedins) D) A posterior pituitary-inhibiting hormone E) T3 and T4

B) Growth hormone-inhibiting hormone (GHIH)

Damage to the liver might impair enzymatic degradation of some hormones (i.e. estrogen). The levels of such hormones in the blood would therefore be expected to: A) Remain unchanged B) Increase C) Decrease

B) Increase

Which of the following chemical messengers is not derived from lipids? A) Prostaglandins B) Insulin C) Cortisol D) Aldosterone E) Estrogens

B) Insulin

Which of the following hormones are controlled by humoral stimuli? A) Triiodothyronine B) Insulin C) Epinephrine D) Norepinephrine E) Cortisol

B) Insulin

Lipophilic hormones bind to _____________ receptors of target cells. A) Membrane-bound B) Intracellular

B) Intracellular

The hypothalamic-hypophyseal tract: A) Connects the hypophysis to the pituitary gland. B) Is partially contained within the infundibulum. C) Conducts aldosterone to the hypophysis. D) Is the site of prolactin synthesis.

B) Is partially contained within the infundibulum.

Chemical signaling that affects neighboring cells is called: A) Autocrine B) Paracrine C) Endocrine D) Neuron

B) Paracrine

Cellular responses to hormones that initiate second-messenger systems include __________. A) Cyclic AMP phosphodiesterase formation of an active second messenger. B) Possible activation of several different second-messenger systems. C) Formation of specific protein kinase that acts on a series of extracellular intermediates. D) Hormone binding to intracellular receptors.

B) Possible activation of several different second-messenger systems.

Which of the following is correctly matched? A) Steroid hormones bind to an intracellular receptor; thyroid hormones bind to a plasma membrane receptor. B) Steroid hormones bind to a cytoplasmic receptor; thyroid hormones bind to a nuclear receptor. C) Steroid hormones bind to a nuclear receptor; thyroid hormones bind to a cytoplasmic receptor. D) Steroid hormones bind to a plasma membrane receptor; thyroid hormones bind to an intracellular receptor.

B) Steroid hormones bind to a cytoplasmic receptor; thyroid hormones bind to a nuclear receptor.

Which of the following is NOT a change typically produced by a hormonal stimulus? A) Activates or deactivates enzymes B) Stimulates production of an action potential C) Alters plasma membrane permeability D) Induces secretory activity

B) Stimulates production of an action potential

What property prevents the hormones of cell-surface receptors from entering the cell? A) The molecules bind to the extracellular domain. B) The molecules are water-soluble and cannot penetrate the lipid-soluble interior of the plasma membrane. C) The molecules are attached to transport proteins that deliver them through the bloodstream to the target cells. D) The ligands are able to penetrate the membrane and directly influence gene expression upon receptor binding.

B) The molecules are water-soluble and cannot penetrate the lipid-soluble interior of the plasma membrane.

A newly developed pesticide has been discovered to bind to an intracellular hormone receptor. If ingested, residue from this pesticide could disrupt the levels of: A) Melatonin B) Thyroid hormone C) Growth hormone D) Insulin

B) Thyroid hormone

Which of the following adrenergic receptors increase cAMP levels? A) ?1 receptors B) ?2 receptors C) ? receptors

C) ? receptors

Lipid-soluble hormones readily diffuse through capillary walls; whereas water-soluble hormones must: A) Be secreted through capillary cells. B) Pass through pores in the capillary endothelium. C) Be secreted through exocytosis, and active transport mechanism. D) Remain in the blood.

C) Be secreted through exocytosis, and active transport mechanism.

Why do steroid hormones have a longer half-life than other hormones? A) Because they are cholesterol. B) Because they are released from the adrenal gland and gonads. C) Because they are bound to proteins carries. D) Because they are exerted in urine or bile.

C) Because they are bound to proteins carries.

The second-messenger mechanism of hormone action operates by ___________. A) Synthesizing more than one hormone at a time. B) Increasing the basal metabolic rate in the target organ. C) Binding to specific receptors and employing the services of G protein and cAMP. D) Altering gene expression in the nuclear DNA.

C) Binding to specific receptors and employing the services of G protein and cAMP.

Modified amino acids that act as hormones are referred to as ________ amines. A) Atavistic B) Syriac C) Biogenic D) Promotive

C) Biogenic

What keeps intracellular receptors from binding to DNA before a hormone bind to the receptor? A) Receptors can't enter the nucleus until the hormone is bound to it B) Transcription factors C) Chaperone proteins (chaperonins)!

C) Chaperone proteins (chaperonins)!

Cells that respond to peptide hormones usually do so through a sequence of biochemical reactions involving receptor and kinase activation. In order for cells to respond, it is necessary for first and second messengers to communicate. This is possible because _____________. A) Peptide hormones are converted by cell membrane enzymes into second messengers. B) Hormones alter cellular operations through direct stimulation of a gene. C) G protein acts as the link between first and second messengers. D) The hormone receptor complex moves into the cytoplasm as a unit.

C) G protein acts as the link between first and second messengers.

Growth factor hormones, such as insulin, bind to which type of receptor? A) Tyrocine kinase receptors B) Intracellular receptors C) G proteins

C) G proteins

If you had to summarize the role of the endocrine system in one word, what would it be? A) Communication B) Development C) Homeostasis D) Growth

C) Homeostasis

Eicosanoids do NOT include ______________. A) Paracrines B) Leukotrienes C) Hydrocortisones D) Prostaglandins

C) Hydrocortisones

Several hormones are synthesized in the hypothalamus and transported to the anterior pituitary gland. The mechanism of transportation from the hypothalamus to the anterior pituitary gland is through the ___________. A) Hepatic portal system B) General circulatory system C) Hypophyseal portal system D) Feedback loop

C) Hypophyseal portal system

The hypophyseal portal system carries hormones from: A) Anterior pituitary to the hypothalamus B) Posterior pituitary to the hypothalamus C) Hypothalamus to the anterior pituitary D) Hypothalamus to the posterior pituitary E) Anterior pituitary to posterior pituitary

C) Hypothalamus to the anterior pituitary

ADH is secreted in response to: A) Overhydration B) Increased volume of body fluids C) Increased osmotic pressure of the body fluids D) High blood pressure

C) Increased osmotic pressure of the body fluids

A student is in a car accident, and although not hurt, immediately experiences pupil dilation, increased heart rate and rapid breathing. What type of endocrine system stimulus did the student receive? A) Humoral B) Hormonal C) Neural D) Positive feedback

C) Neural

Which of the following general chemical categories is NOT represented by a group of hormones? A) Modified amino acids B) Polypeptides and proteins C) Nucleic acids D) Steroids

C) Nucleic acids

What intracellular substance degrades cAMP, thus inactivating the response to a hormone? A) Phospholipase C B) Protein kinase C C) Phosphodiesterase D) Adenylyl cyclase

C) Phosphodiesterase

Which of the following does NOT influence the response of the target cell? A) Number of receptors for the hormones. B) Concentration of hormone in the blood. C) Rate of blood flow. D) Affinity for binding between hormone and receptor.

C) Rate of blood flow.

Virtually all of the protein or amino acid-based hormones exert their effects through intracellular __________. A) Deactivating ions B) Calcium C) Second-messengers D) Nucleotides

C) Second-messengers

Which of the following occurs in situations where more than one hormone produces the same effect at the target cell and their combines effects are amplified? A) Summation B) Permissiveness C) Synergism D) Antagonism

C) Synergism

When the effects of one hormone reinforce the activity of another hormones on the same target cell, the interaction is said to be: A) Agnostic B) Permissive C) Synergistic D) Antagonistic

C) Synergistic

The ability of a specific tissue or organ to respond to the presence of a hormone is dependent on _________. A) The location of the tissue or organ with respect to the circulatory pathway. B) The membrane potential of the cells or the target organ. C) The presence of the appropriate receptors on the cells of the target tissue or organ. D) Nothing - all hormones of the human body are able to stimulate any and all cell types because hormones are powerful and non-specific.

C) The presence of the appropriate receptors on the cells of the target tissue or organ.

Most peptide hormones are easily transport in the blood plasma because: A) They all have transport proteins B) They are made of lipids C) They are water-soluble D) They are very small

C) They are water-soluble

Which hormone's receptor is always bound to DNA, even when the receptor is empty? A) Insulin B) Cortisol C) Thyroid hormone

C) Thyroid hormone

In circumstances where the body requires prolonged or increased levels of a hormone, the DNA of a target cell will specify the synthesis of more receptors in the surface of the cells of the target organ. This is known as ___________. A) Sensitivity increase B) Cellular affinity C) Up-regulation D) Down-regulation E) A stressor reaction

C) Up-regulation

After a lipid-solution hormone is bound to its intracellular receptor, what does the hormone complex? A) Phosphorylates a protein B) Directly alters protein synthesis at the ribosome C) Activates a protein kinase D) Acts as a transcription factor and binds to DNA, activating a gene.

D) Acts as a transcription factor and binds to DNA, activating a gene.

Which of the following is a mechanism of stimulating hormone release? A) Humoral regulation B) Hormonal regulation C) Neural regulation D) All of the above

D) All of the above

Which of these can regulate the secretion of a hormone from an endocrine tissue? A) Other hormones B) Negative-feedback C) Humoral substances in the blood D) All of these

D) All of these

When eicosanoids bring about cellular changes within the cell from which they were formed, the process is called ______________ simulation. A) Merocrine B) Paracrine C) Eccrine D) Autocrine

D) Autocrine

The most common second-messenger mechanism of hormone action operates by: A) Synthesizing more than one hormone at a time. B) Increasing the basal metabolic rate in the target organ. C) Altering gene expression in the nuclear DNA. D) Binding to specific receptors and employing the services of G proteins and cAMP.

D) Binding to specific receptors and employing the services of G proteins and cAMP.

Which of the following is NOT a change that may be caused by a hormonal stimulus? A) A change in membrane potential B) The stimulation of genetic event resulting in protein synthesis C) An increase in enzymatic activity D) Direct control of the nervous system

D) Direct control of the nervous system

Which of the following is NOT a type of hormone interaction? A) Permissiveness B) Synergism C) Antagonism D) Feedback

D) Feedback

Regulating hormones from the hormones: A) Enter venous circulation and travel to the heart, which pumps the hormone-contain in blood to the pituitary. B) Enter the haptic portal system, which feeds the pituitary. C) Travel by arteries to the pituitary. D) First enter into the hypophyseal portal system.

D) First enter into the hypophyseal portal system.

The thyroid hormone, thyroxin is formed: A) From cholesterol B) From changes to carbohydrates C) From other hormones D) From changes to an amino acid

D) From changes to an amino acid

Which stimulus would increase the rate of growth hormone secretion? A) High blood glucose levels B) High blood protein levels C) Deep sleep D) High somatostatin levels

D) High somatostatin levels

Chemical substances secreted by cells into the extracellular fluids and that regulate the metabolic functions of other cells in the body are called: A) Enzymes B) Antibodies C) Proteins D) Hormones

D) Hormones

One of the least complicated of the endocrine control systems directly responds to changing blood levels of ions and nutrients. Which of the following describes this mechanism? A) Carbohydrate oxidation B) Catabolic inhibition C) Protein synthesis D) Humoral stimulation

D) Humoral stimulation

ADH: A) Increases urine production B) Promotes dehydration C) Is produced in the adenohypophysis D) Is inhibited by alcohol

D) Is inhibited by alcohol

What happens to the protein calmodulin when hormones bind to it? A)It is destroyed B) It releases ATP C) It produces a hormone D) It activates enzymes

D) It activates enzymes

The neurohypophysis or posterior lobe of the pituitary gland is not a true endocrine gland disorder because: A) It is strictly part of the neural system and has little or nothing to do with hormone release. B) Embryonically, it was an endocrine tissue, but in the adult human, it is no longer functional. C) It is unable to function as an endocrine tissue because it is an actual part of the neural system due to its location. D) It is only a hormone storage area that receives hormones from the hypothalamus for release.

D) It is only a hormone storage area that receives hormones from the hypothalamus for release.

The milk ejection reflex is an important effect of: A) Prolactin B) Estrogen C) Progesterone D) Oxytocin E) FSH

D) Oxytocin

When the activity of one hormone requires that of a second hormones, the interaction is said to be: A) Synergistic B) Agonistic C) Antagonistic D) Permissive

D) Permissive

The sell turcica is the location of which gland? A) Thymus B) Adrenal C) Pineal D) Pituitary

D) Pituitary

Anterior pituitary cells called mammotropes (lactotropes) secrete: A) Adrenocorticotropic hormone B) Follicle-stimulating hormone C) Growth hormone D) Prolactin

D) Prolactin

Most hormones are made up of chains of amino acids and are therefore: A) Catecholamines B) Biogenic amines C) Steroids D) Proteins

D) Proteins

In an ECG, the T-wave represents: A) Depolarization of the atria B) Depolarization of the ventricles C) Repolarization of the atria D) Repolarization of the ventricles.

D) Repolarization of the ventricles.

Cells that respond to a particular hormone are called: A) Receptor cells B) Effector cells C) Secretory cells D) Target cells E) Active cells

D) Target cells

Peptide hormones must bind to a plasma membrane hormone receptor because: A) They are lipophilic B) They are non-polar C) They are hydrophobic D) They are polar E) They are too small

D) They are polar

Which of the choices below is NOT a factor required for target cell activation by hormone receptor interaction? A) Number of receptors for the hormone. B) Strength of the bond between the receptor and the hormone. C) Blood levels of hormones. D) Type of hormone.

D) Type of hormone.

Reduced hormone concentration in the blood often causes target cells to: A) Up-regulate receptors in order to decrease cell sensitivity. B) Down-regulate receptors in order to decrease cell sensitivity. C) Down-regulate receptors in order to increase cell sensitivity. D) Up-regulate receptors in order to increase cell sensitivity.

D) Up-regulate receptors in order to increase cell sensitivity.

Down-Regulation:

Decreased target cell response to simulation. Decreased number of hormone receptors. Desensitization resulting from prolonged exposure.

Steroid hormones are lipids, derived from: A) Polypeptides B) Glycerol C) Amines D) Nucleic acids E) Cholesterol

E) Cholesterol

All of the following are hormones of the anterior pituitary except: A) Human growth hormone B) Follicle-stimulating hormone C) Adrenocorticotropic hormone D) Prolactin E) Oxytocin

E) Oxytocin

Up-Regulation:

Increased number of hormone receptors. Increased hormone levels. Increased target cell response to stimulation.

Humoral Stimuli:

Responds to changes in blood ion concentration. Simplest of controls. Ex: Insulin Ex: Parathyroid hormones

Neural Stimuli:

Stimulation by nerve fibers. Ex: Sympathetic nervous system Ex: Hypothalamic stimulation of ADH

Hormonal Stimuli:

Tropic hormones. Involves most hormones. Ex: Anterior pituitary hormones