Category - Definitions

Query - What definition best describes the term below?

Reversal

Category - Term Recognition

Query - What term does the description below refer to?

(Terms are shown on left, descriptions in middle, figures on right)

Phorbol Esters | A group of compounds that are not carcinogenic themselves, but stimulate the formation of tumors when applied along with a carcinogen to experimental animals. |

Abscisic Acid | A sesquiterpene class of plant hormones derived from isopentenyl pyrophosphate |  | Adenylate cyclase | A membrane-bound enzyme that catalyzes synthesis of cAMP in response to hormones, such as epinephrine or glucagon. |  | Adipocyte | Cells that are specialized for storing triacylglycerols and for releasing them to the blood in the form of fatty acids and glycerol as required. | Figure 23.1 | Adrenal corticotropic hormone (ACTH, also called -corticotropin) | A hormone secreted from the anterior pituitary that stimulates the adrenal cortex to produce glucocorticoids and mineralocortiocids, which in turn act on a number of tissues. |  | Adrenergic Receptors | Cell-surface receptors that bind epinephrine and norepinephrine. There are several different types with somewhat different ligand specificities and effects. |  | Agonist | A substance that mimics the cellular effects of a natural compound (such as a hormone or neurotransmitter) by binding to and activating the same cellular receptor. |  | Antagonist | A substance that counteracts the cellular effects of a natural compound (such as a hormone or neurotransmitter) by binding to the cellular receptor for the compound and blocking its action. |  | Atrial natriuretic Factor | A protein which controls blood volume. It binds to a receptor that has both a guanylate cyclase activity and a predicted protein serine/threonine kinase activity. |  | Auxins | A class of plant hormones derived from tryptophan metabolism. |  | Catecholamines | A class of molecules, such as epinephrine, which are derived from tyrosine and contain a benzene ring with more than one hydroxyl group. |  | Cholera toxin | A toxin of Vibrio cholerae that cleaves NAD+ and transfers its ADP-ribose moiety to a specific site in the subunit of G s |  | Corticotropin Releasing Factor (CRF) | A 41-residue polypeptide released by the hypothalamus that stimulates the anterior pituitary to release ACTH. |  | CREB (Cyclic AMP response element binding protein) | A protein that cAMP binds to, which stimulates transcription of a class of genes, including cellular hormone receptor proteins. |  | Cytokinins | A class of plant hormones continine purine bases with a terpenoid side chain. |  | Diabetes mellitus | A disease caused by a deficiency in the action of insulin in the body, resulting either from low insulin levels or from inadequate insulin levels combined with unresponsiveness of the target cells to insulin. The disease is manifested primarily by disturbances in fuel homeostasis, including hyperglycemia (abnormally high blood glucose levels). |  | Diethylstilbestrol | A synthetic estrogen that is more than 10 times more potent than natural estrogens. |  | Endocrine Cells | Cells that synthesize hormones and release them into the circulation. |  | Epinephrine | A compound which, when released from presynaptic nerve endings, acts as a neurotransmitter and, when released by the adrenal medulla, acts as a hormone to activate adenylate cyclase in increase cAMP levels in target cells. |  | Ethylene | A plant hormone which comes from the methionyl moiety of S-adenosylmethionine |  | Exocrine Cells | A cell that secretes a substance that is excreted through a duct either into the alimentary tract or to the outside of the organism. |  | G proteins | A class of proteins that transduce the signal received at the adrenergic receptor to adenylate cyclase, which they stimulate to catalyze synthesis of cAMP. |  | G i | A closely related family of G proteins involved in responses that inhibit adenylate cyclase. |  | Gibberellins | A diterpene class of plant hormones derived from isopentenyl pyrophosphate. |  | Glucagon | A 3.5 kD polypeptide synthesized by A cells of the islets of Langerhans in the pancreas. The hormone is released in response to low blood glucose levels. | Figure 23.2 | G s | A family of G proteins involved in stimulation of adenylate cyclase. | Figure 23.12 | Hormone Response Elements (HREs) | DNA sites that steroid hormone-hormone receptor complexes interact with to affect transcription of genes near the site. | Table 23.6 | Hypothalamus | A specialized center of the brain that receives and processes sensory inputs from the environment via the central nervous system and produces a number of hormones, including the releasing factors. | Figure 23.8 | Indole-3-acetic acid | The most common auxin hormone found in plants. |  | Insulin | A 5.8 kD protein synthesized in the B cells of the islets of Langerhans of the pancreas. It is involved in controlling blood glucose levels and stimulates cells to take up glucose from the blood. | Figure 23.2 | Insulin receptor | A glycoprotein with an 22 tetrameric structure. In the cellular membrane, when it binds insulin on the outer surface of the cell, it stimulates activation of a protein tyrosine kinase activity on the inside of the cell |  | Intracellular hormone receptors |  | Figure 23.16 | Intracellular Receptors | A class of hormone receptors that exert their effects at the gene level. |  | Islets of Langerhans | Clusters of pancreatic cells that act as endocrine tissue. There are four different cell types found. |  | Isoproterenol | An agonist used to treat asthma that acts by interacting with one specific class of adrenergic receptor. |  | MAPK (Mitogen-activated Protein Kinase) | A class of proteins phosphorylated by MAPKK as part of the central growth factor activation pathway. | Figure 23.23 | MAPKK | A class of proteins phosphorylated by MAPKKK as part of the central growth factor activation pathway. It phosphorylates MAPK. | Figure 23.23 | MAPKKK | A class of proteins phosphorylated as a result of ras activation in the central growth factor activation pathway. It phosphorylates MAPKK. The proto-oncogene raf is a member of this family. |  | Membrane-bound Receptors | A class of hormone receptors found in the outer membranes of cells. They may act either through three mechanisms, 1. Via a second messenger systems which stimulates production of event inside the cell, 2. As ion channels, which open or close in response to hormone binding, and 3. As a transmembrane protein with a receptor on the outside and a catalytic domain on the inside of the cell that is activated by hormone binding. | Figure 23.7 | Mitogen | A factor that stimulates mitosis |  | Myristic Acid | A fatty acid containing 14 carbons often attached to the -subunit of G proteins. |  | Oncogene | An altered cellular gene associated with cellular transformation and cancer. | Figure 23.19 | Oxytocin | A hormone which stimulates uterine contractions in labor. |  | p53 | A protein of 53 kD in mass that acts in eukaryotic cells as a tumor suppressor. It is involved in regulating the cell cycle. |  | Pertussis Toxin | A toxin produced by Bordetella pertussis, which binds the subunit of G i protein. It causes whooping cough, lowers blood glucose, and produces hypersensitivity to histamine. |  | Phosphoinositide System | A cellular system that in response to a hormonal stimuls activate a reaction that stimulates two intracellular messengers, sn-1,2-diacylglycerol (DAG) and inisitol 1,4,5 trisphosphate (InsP 3). | Figure 23.14 | Phospholipase C | An enzyme stimulated by the phosphoinositide system. It catalyzes cleavage of phosphatidylinositol 4,5-bisphosphate (PIP2) to create sn-1,2-diacylglycerol (DAG) and inisotol 1,4,5 trisphosphate (InsP 3). | Figure 23.14 | Platelet-Derived Growth Factor (PDgf) | A growth factor that interacts with cell surface receptors to stimulate the hydrolysis of phosphatidylinositol. |  | Prenylation | Attachment of a C 20 isoprenoid moiety onto a molecule. |  | Preproinsulin | A 105-residue polypeptide that is the precursor of proinsulin and the ultimate source of insulin. |  | Proinsulin | An 81-residue polypeptide that is an immediate precursor of insulin. It is derived from preproinsulin. |  | Propranolol | An antagonist of a class of adrenergic receptors which control blood pressure and heartbeat rate. |  | Proto-oncogene | A cellular gene important in controlling events relating to the growth of the cell. Alteration of the sequence, function, or amount of this gene product may result in transformation of the cell. Such an altered gene is referred to as an oncogene. | Figure 23.19 | Releasing factors | Hormones released by the hypothalamus that act to stimulate the anterior pituitary to release specific hormones | Figure 23.8 | Retrovirus | A single-stranded RNA virus that goes through a DNA phase as part of its life cycle, due to the presence of reverse transcriptase. |  | Reverse Transcriptase | A viral enzyme in retroviruses that synthesizes DNA from an RNA template. |  | Rhodopsin | An abundant membrane protein in the outer segment of rod cells of the retina. Photochemical changes cause this protein to activate transducin to bind GTP. |  | RU486 | A drug that binds to progesterone receptors and blocks events essential to implantation of a fertilized ovum in the uterus. |  | Secretin | A substance releasd in the upper small intestine that acts in the stomach to stimulate the flow of gastric juice as an aid to digestion. |  | Signal Transduction | The process whereby molecules external to a cell can exert their effects inside of a target cell. |  | Tamoxifen | A drug that binds to estrogen receptors, but does not activate estrogen-responsive genes. It antagonizes estrogen binding in residual tumor cells after surgery. |  | Transducin | A protein that, upon photochemical stimulation of rhodopsin, is stimulated to bind GTP and activate a phosphodiesterase to cleave cGMP, stimulating a visual cascade of reactions that signal the brain. |  | Transformation | With respect to cells and cancer, a process whereby cell lose normal growth control mechanisms and in cell culture continue to proliferate under conditions that arrest the growth of normal cells. The cells will produce a tumor if injected into animals. |  | Transforming Growth factor | A growth factor that binds to a receptor with a protein serine/threonine kinase activity. |  | Tropic Hormones (Tropins) | Pituitary hormones that act on other endocrine glands. |  | Zinc Finger | A protein structural motif involving zinc and cysteine residues found in many proteins that interact with DNA. This portion of the protein is the part that binds to the DNA. | Figure 23.17

Category - General

Query - Is contained in the left column below, solution in middle, figure on right

Reversal - there is no reversal

Questions on left, solution in middle, figures on right

At rest, what is the primary energy source used by muscles? | Fatty acids |  | At what concentration range do hormones typically work? | Micromolar to picomolar |  | Besides fatty acids, what fuels are used by the heart? | glucose, lactate, and ketone bodies. | Figure 23.1 | Decreasing levels of Malonyl-CoA causes what response in the liver? | Carnitine acyltransferase I is not inhibited, permitting transport of fatty acids to the mitochondrion, and starting fatty acid breakdown. |  | During exertion, what is the primary energy source used by muscles? | Glucose |  | During starvation, what do muscles use for energy? | Their own protein | Figure 23.1 | High blood glucose levels normally cause what response in the liver? | Insulin stimulates uptake of glucose, stimulating glycogen synthesis and inhibiting glycogen breakdown. Acetyl-CoA carboxylase is activated, stimulating fatty acid synthesis. Increasing amounts of fat stimulate VLDL synthesis for transport of the fat to adipose tissue. | Figure 23.4 | How do different cells produce different assemblages of hormones from pro-opiomelanocortin? | By cleaving the pro hormone at different sites in the polypeptide. |  | How do G proteins derive their name? | They bind guanine nucleotides. |  | How do growth factors differ from hormones? | The growth-stimulating activities of growth factors are continuous, rather than being short-lived in response to a burst of secretion. |  | How do most pituitary hormones work? | They stimulate the endocrine glands to produce hormones that exert the ultimate actions on target tissues. | Figure 23.8 | How do mutations at codon 12 affect ras? | They inhibit the GTPase activity, leaving the protein in an activated state. |  | How do neurotransmitters differ from hormones? | Neurotransmitters act immediately across a synaptic junction from their sites of release. Hormones traverse the blood stream and may act a long distance from their point of release. |  | How do pheromones differ from hormones? | Pheromones are transmitted between cells of different organisms. |  | How do steroid hormones affect the cell? | They control the activities of specific genes. |  | How does binding of insulin affect the insulin receptor? | It activates a tyrosine protein kinase activity on the domain of the receptor on the inside of the cell. |  | How does cholera toxin inactivate the GTPase of the subunit of G s, converting it to constant stimulation of adenylate cyclase? | It cleaves NAD+ and transfers its ADP-ribose moiety to a specific site in the subunit of G s, inhibiting the GTPase. |  | How is breakdown of fat in adipocytes largely controlled? | Via activation of hormone-sensitive lipase. |  | How is the activity of specific genes controlled by steroid hormones? | The regulatory effects occur at the level of transcription of steroid-responsive genes. |  | How is the glucose transporter protein affected by insulin? | Its cellular location is changed from the cytosol to the cell surface. |  | How long of a period of time without food intake before the body exhausts its supply of glucose from glycogen? | Several hours |  | How much energy is stored in triacyglycerols in an average-sized human? | 565,000 kJ or 135,000 kcal |  | In tumor cells, what proteins involved in signal transduction are often mutated? | Protein kinases, G proteins, nuclear receptors, growth factors, and growth factor receptors. |  | Increasing levels of Malonyl-CoA causes what response in the liver? | Carnitine acyltransferase I is inhibited, preventing transport of fatty acids to the mitochondrion, and stopping fatty acid breakdown. |  | Mutations in the retinoblastoma gene are associated with what type of tumor? | Eye |  | On the 40th day of starvation, what percentage of the brain's energy is derived from ketone bodies? | 67% |  | On the third day of starvation, what percentage of the brain's energy is supplied by ketone bodies? | 33% |  | Release of epinephrine stimulates what processes? | Glycogen breakdown, inhibition of glycogen synthesis, triacylglycerol breakdown in adipose tissue, reduced glucose uptake by muscle, increased blood glucose, inhibits insulin secretion, stimulates glucagon secretion, increased glucose production and release by the liver. |  | The ratio of what two plant hormones is important in determining whether a plant will grow or differentiate? | Cytokinins and auxins. |  | Under normal conditions, what compound does the brain use exclusively to meet its energy needs? | Glucose |  | Under what condition is epinephrine released from the adrenal medulla? | When glucose levels are low or under conditions of 'flight or fight' |  | What activity does protein kinase C carry out? | Phosphorylation of specific serine and threonine residues in target proteins. |  | What activity of G s limits the length of G s activation? | A slow GTPase activity. |  | What alternate source of energy does the brain use when glucose is not available in sufficient quantities? | Ketone bodies |  | What amino acid is produced in muscle as a result of transamination of pyruvate? | Alanine | Figure 23.1 | What are G proteins involved in olfactory cells in the nose called? | G olf |  | What are some of the target proteins phosphorylated by protein kinase C? | Calmodulin, insulin receptor, -adrenergic receptor, glucose transporter, HMG-CoA reductase, cytochrome P-450, and tyrosine hydroxylase. |  | What are the classes of catecholamine receptors? | 1-, 2-, 1-, and 2-adrenergic receptors |  | What are the classes of molecules acting as extracellular messengers? | Hormones, neurotransmitters, growth factors, and pheromones. |  | What are the dissociation constants of binding of hormones to receptors? | 01. uM to 1.0 pM |  | What are the five major classes of plant hormones? | Gibberellins, abscisic acid, cytokinins, auxins, and ethylene |  | What are the four hormones secreted by pancreatic endocrine cells? | Glucagon, Somatostatin, Pancreatic hormone, and Insulin |  | What are the major fuel storage forms in animals? | Triacylglycerols (fats/oils), protein, glycogen |  | What are the multiple hormones found on pro-opiomelanocortin? | -lipotropin, -lipotropin, -melanocyte-stimulating hormone (MSH), -MSH, -MSH, endorphin, enkephalin, and ACTH. | Figure 23.10 | What are the principal classes of steroid hormones regulating gene expression? | Glucocorticoids, esterogens, progesterone, androgens, 1,25-dihydroxyvitamin D3, thyroid hormones, and ecdysone (insects) |  | What are the three chemical categories in which hormones can be placed? | 1. Peptides (polypeptides), such as insulin or glucagon 2. Steroids, including glucocorticoids and the sex hormones 3. Amino acid derivatives, including the catecholamines and thyroxine. |  | What are the three proteins involved in cAMP-dependent signal transduction? | 1. A hormone receptor, 2. Adenylate cyclase, and 3. A G protein |  | What are the three ways in which membrane bound hormone receptors may exert their effects? | 1. Interact with G proteins to influence the synthesis of second messengers 2. As ion channels, which open or close in response to hormone binding, and 3. As a transmembrane protein with a receptor on the outside and a catalytic domain on the inside of the cell that is activated by hormone binding. |  | What are the tissues that secrete hormones called? | Endocrine glands | Figure 23.6 | What are the two second messengers of the phosphoinositide system? | sn-1,2-diacylglycerol (DAG) and inositol 1,4,5 triphosphate (InsP 3). |  | What are two prominent tumor suppressor genes? | p53 and the retinoblastoma gene |  | What byproduct of glycolysis accumulates in muscles during exercise? | Lactate | Figure 23.1 | What catalytic activity does ras have? | A slow GTPase activity. |  | What causes insulin-resistant diabetes? | Anything that causes patients not to respond to therapeutic doeses of insulin. These can be mutations in the insulin receptor or mutations that affect the intracellular activities that promote glucose utilization. |  | What center of the brain acts as the 'master coordinator' of hormone action? | Hypothalamus |  | What chemical processing happens on almost all peptide hormones that are made? | Proteolytic cleavage of an inactive precrursor to activate it. |  | What cofactors are required for protein kinase C activity? | Calcium and phosphatidylserine |  | What do gibberellins promote in plants? | Growth |  | What does loss of p53 function lead to? | Tumor formation. |  | What effect do growth factors, such as PDgf have on the phosphoinositide system? | They stimulate the hydrolysis of phosphatidylinositol |  | What effect do phorbol esters have on protein kinase C? | They can activate the enzyme independently of diacylglycerol. |  | What effect does calcium influx have on muscle cells? | Muscular contraction is stimulated. |  | What effect does cAMP have in the cell? | Activates cAMP-dependent protein kinase, with consequent phosphorylation of target proteins, such as phosphorylase b kinase in cells that activate glycogen phosphorylysis. |  | What effect does cholera toxin have? | Through ADP-ribosylation of the subunit of G s, the GTPase activity of the polypeptide is inhibited and G s constantly stimulates adenylate cyclase to make cAMP. |  | What effect does diacylglycerol have on protein kinase C? | Increases its affinity for calcium |  | What effect does G i have on adenylate cyclase in response to hormone signalling? | Inhibition |  | What effect does glucagon have in liver cells? | Increase concentration of cAMP,which stimulates glycogen breakdown and gluconeogenesis while inhibiting glycogen synthesis and glycolysis | Figure 23.3 | What effect does glucagon have on adipose cells? | Raises cAMP levels, which promotes triacylglycerol breakdown via phosphorylation of hormone-sensitive lipase, yielding glycerol and fatty acids |  | What effect do auxins have? | They stimulate growth of the main shoot and inhibit lateral shoot development. |  | What enzyme does diacylglycerol activate in the phosphoinositide response? | Membrane-bound protein kinase C | Figure 23.14 | What enzyme is lacking in adipocytes that requires the cell to undergo glycolysis to produce DHAP for glycerol-3-phosphate synthesis? | Glycerol kinase |  | What enzyme is stimulated in the phosphoinositide system to create the two second messengers? | Phospholipase C | Figure 23.14 | What enzymes/molecules does the liver use to regulate blood glucose levels? | Glucokinase (a form of hexokinase with a high KM for glucose) and a transport protein, glucose transporter, which also has a high KM for glucose. |  | What extracellular molecules act to increase cAMP levels? | Glucagon and epinephrine |  | What G protein is targeted in whooping cough? | G i |  | What G protein subunit is myristoylated? |  |  | What growth factor receptors contain tyrosine kinase activities? | Epidermal growth factor, platelet-derived growth factor, colony-stimulating factor 1, fibroblast growth factor, insulin-like growth factor 1, insulin growth factor. | Figure 23.15 | What happens at the cellular level in diabetes? | Glucose accumulates in the blood while cells are starved of nutrients. Metabolic responses to fasting may be invoked. Blood pH may fall. Ketone bodies may be produced and used. Kidney cells cannot process the high levels of glucose in the blood, so glucose spills into the urine. |  | What hormones act through intracellular receptors? | Steroids, thyroid hormones, hormonal forms of vitamin D, and retinoids. |  | What important function does the liver have with respect to glucose? | It controls the level of blood glucose | Figure 23.1 | What inhibits hydrolysis of the last phosphate from inositol triphosphate? | Lithium |  | What is is a primary mechanism of regulating hormone action? | Feedback regulation. | Figure 23.9 | What is the 'prepro' structure of all known polypeptide hormones? | The 'pre' portion is a signal sequence for cellular export and the 'pro' part is a piece that must be further removed for maturation of the hormone. |  | What is the common cause of insulin-dependent diabetes? | Autoimmune destruction of the B cells of the pancreas that produce insulin. |  | What is the main fuel used by the heart? | Fatty acids | Figure 23.1 | What is the major difference in stability between epinephrine and glucagon? | Epinephrine has a much shorter lifetime. |  | What is the molecular stimulus of the visual cascade? | Cleavage of cGMP by a phosphodiesterase. |  | What is the primary target of glucagon? | The liver |  | What is the range of human daily caloric intake? | 1500-6000 kcal or 6000 to 25,000 kJ per day |  | What is the response to ionic environment in many nerve and muscle cells to activation of adenylate cyclase? | An increase in movement of calcium into the cell. |  | What is the subunit structure of G s, GK and other G proteins? | Trimeric () |  | What kinds of molecules are the subunits of G proteins known to affect? | Table 23.4 |  | What metabolic pathway are blood cells almost exclusively dependent upon? | Anaerobic glycolysis |  | What metal atom is bound by all known hormone receptor proteins? | Zinc | Figure 23.17 | What modification happens often to the subunit of G proteins? | Prenylation |  | What moiety is often attached to the subunit of G proteins? | Myristic acid |  | What molecular effect does auxin have on cells? | Pumping protons out of the cell, raising intracellular pH. This brings about partial wall degradation, a necessary event for growth to occur. |  | What molecule in muscles generates ATP without the need for metaboliziing fuels? | Creatine phosphate |  | What molecule in the liver governs whether fatty acids are synthesized or broken down? | Malonyl-CoA |  | What molecule is the prescursor of the two messengers of the phosphoinositide system? | 4,5-bisphosphate (PIP2) | Figure 23.14 | What molecule that acts like a hormone, but instead of interacting with a cellular receptor, it instead diffuses through the cell membrane and stimulates cGMP synthesis? | Nitric oxide |  | What molecules act through membrane-bound receptors? | Peptide hormones and epinephrine |  | What molecules can act as second messengers of the hormone response, resulting from hormone binding to the cell surface receptor? | Cyclic AMP, cyclic GMP, calcium, diacylglycerol, and protein substrates | Figure 23.7 | What mutation converts the ras gene into an oncogene? | A mutation in the twelth codon. |  | What nucleotide does ras bind? | GTP/GDP |  | What organ is the major site of fatty acid synthesis? | Liver | Figure 23.1 | What organ makes most of the ketone bodies? | Liver | Figure 23.1 | What organ releases epinephrine to act as a hormone? | Adrenal medulla |  | What organ uses lactate and alanine from muscle, glycerol from adipose tissue, and amino acids to make glucose? | Liver | Figure 23.1 | What organelle involved in energy metabolism is missing in blood cells? | Mitochondria |  | What percentage of the total energy of the human body does the brain use? | 0.15 |  | What percentage of the total glucose for a human at rest does the brain use? | 0.6 |  | What percentage of the total glycogen in the body is stored in muscles? | 0.75 |  | What percentage of the total oxygen consumed by the human body does the brain use? | 0.2 |  | What process affecting a second messenger, is inhibited by lithium? | Hydrolysis of the last phosphate from inositol triphosphate. |  | What protooncogene helps mediate a growth factor signal by interacting with the growth factor receptor and help stimulate a kinase cascade that ultimately affects transcription? | ras | Figure 23.23 | What state are G proteins bound with GDP in? | Inactive |  | What state are G proteins bound with GTP in? | Active |  | What stimulates G s to exchange GDP for GTP? | Changes in the hormone receptor on binding hormone that stimulates and interaction with the protein. The receptor-G s interaction favors the exchange of GDP with GTP on the G s. |  | What structural motif is present in all known steroid hormone receptor proteins? | Zinc finger | Figure 23.17 | What subunit of the G protein is ras similar to? |  |  | What tissue of the body has the most densely packed mitochondria? | Heart |  | When stimulated, what is the effect of the phosphoinositide signalling system? | Release of calcium from the endoplasmic reticulum. | Figure 23.14 | Where are auxins synthesized? | In apical buds (at the tip) of growin shoots. |  | Where are cytokinins produced in plants? | In the roots |  | Where are hormones secreted? | Directly into the blood stream |  | Where are triglycerols stored in the body? | Adipose tissue |  | Where do steroid hormones act on cells? | Intracellularly, within the nucleus. |  | Where is glycogen stored in the body? | Mostly in the liver and muscle. |  | Where is most of the protein found in the body? | Skeletal muscle |  | Where is secretion of hormones ultimately controlled? | Central nervous system. |  | Which G protein subunit is prenylated? | (usually) |  | Which hormone will normally be produced in response to a meal? | Insulin |  | Which hormones will be more likely to be stimulated between meals? | Glucagon or epinephrine |  | Which pituitary hormone acts directly on mammary glands to stimulate them to produce milk? | Prolactin |  | Which plant hormone counteracts the effects of most of the other plant hormones? | Abscisic acid |  | Which plant hormone inhibits germination, growth, budding, and leaf senescence? | Abscisic acid |  | Which plant hormone inhibits seedling growth? | Ethylene |  | Which plant hormone is considered a hormone of senescence? | Ethylene |  | Which plant hormone redirects auxin transport to promote transverse rather than longitudinal growth of plants? | Ethylene |  | Which plant hormone stimulates fruit ripening? | Ethylene |  | Which subunit of G s is the 'active' form, which binds GTP and has GTPase activity? |  |  | Which subunit of the insulin receptor spans the membrane and contains the protein kinase activity? | subunit |  | Why can the body not exist solely from metabolism of acetyl-CoA from fatty acid breakdown? | The brain requires either glucose or ketone bodies for energy. |  | Why is muscle glycogen not a source of glucose for the rest of the body? | Muscles lack glucose-6-phosphatase necessary for release of free glucose from cells. |  | Why must the brain generate ATP in large quantities? | To maintain the membrane potentials essential for transmission of nervous impulses. |

What general processes does insulin promote? | 1. Uptake of fuel substrates into some cells. 2. Storage of fuels (lipids and glycogen). 3. Biosynthesis of macromolecules (nucleic acids and proteins). |  | What specific processes does insulin promote? | 1. Uptake of glucose in muscle and adipose tissue. 2. Activation of glycolysis in liver. 3. Increased synthesis of fatty acids and triacylglycerols in liver and adipose tissue. 4. Inhibition of gluconeogenesis in liver. 5. Increased glycogen synthesis in liver and muscle.

6. Increased uptake of amino acids into muscle with consequent activation of protein synthesis.

7. Inhibition of protein degradation.

8. Transport of the glucose transporter protein from the cytosol to the cell surface.

What molecular or cellular abnormalities can bring about the various types of diabetes? | 1. Autoimmune destruction of the B cells of the pancreas. 2. Mutations affecting the amino acid sequence of the processed insulin. 3. Mutations affecting the amino acid sequence so that preproinsulin or pro insulin cannot be process to insulin.

4. Mutations affecting the structure of the insulin receptor on cells.

5. Mutations that affect intracellular activities that promote glucose utilization.

What mechanisms do hormones use in exerting their effect on cells?

1. Enzyme activation or inhibition via second messengers.

2. Stimulation of the synthesis of particular proteins, through activation of specific genes.

3. Selective increases in the cellular uptake of certain metabolites

What is the hierarchy of hormone action?

1. The central nervous system transmits signals to the hypothalamus.

2. The hypothalamus produces factors that either stimulate or inhibit the release of hormones form the pituitary.

3. Hormones released by the pituitary stimulate other endocrine glands.

4. Hormones from targeted endocrine glands act on specific target tissues and elicit a metabolic response.

5. Alternatively, a pituitary hormone, such as prolactin, may act directly on a target tissue.

6. The action of a hormone sets in motion events that ultimately limit that action.

What are the steps in signal tranduction through the adrenergic receptor? | 1. Hormone binding to receptor. 2. Receptor interaction with G s, stimulating release of GDP and association of GTP with G s. 3. Stimulation of adenylate cyclase by G s. 4. Stimulation by cAMP of protein phosphorylation. 5. Stimulation or inhibition of metabolic processes |  | What are some cellular processes controlled by the phosphoinositide second messenger system? | Amylase secretion Insulin release Contraction Glycogenolysis Platelet Aggregration

DNA synthesis

Histamine secretion

DNA synthesis

Fertilization

Phototransduction

Prolactin secretion

What is the sequence of events in ras' activation of the central growth factor activation pathway? | 1. Hormone receptor binds growth factor. 2. Receptor autophosphorylates tyrosine residue. 3. Phosphorylated receptor recruits exchange factors that stimulate GDP-GTP exchange on ras. 4. Ras activates cascade of mitogen-activated protein kinases.

5. Transcription factors are phosphorylated and bind to specific DNA sites, activating gene transcription.

Category - General

Query - What are the normal cellular activities of the gene products of the following oncogenes?

Reversal - there is no reversal

oncogene on left, activity in center, figure on right

|  |  | sis | Platelet-derived growth factor |  | erbB, neu | Epidermal growth factor |  | fms | Colony-stimulating factor 1 receptor |  | trk | Nerve growth factor receptor |  | ros | Insulin receptor |  | kit | PDgf receptor |  | flg | Fibroblast growth factor receptor |  | src | Protein tyrosine kinase |  | abl | Protein tyrosine kinase |  | raf | Protein serine kinase |  | gsp | G protein subunit |  | ras | GTP/GDP binding protein |  | jun | Transcription factor AP-1 |  | fos | Transcription factor AP-1 |  | myc | DNA-binding protein |  | erbA | Thyroid receptor |

Category - General

Query - What proteins are affected by the following steroid hormone?

Reversal - there is no reversal

hormone on left, proteins in center, figure on right

Glucocorticoids | Tyrosine aminotransferase Tryptophan oxygenase -Fetoprotein Metallotheionein Glutamine synthetase

Phosphoenolpyruvate carboxylase

Estrogens

Ovalbumin

Lysozyme

Vitellogenin

apo-VLDL

Progesterone

Ovalbumin

Avidin

Uteroglobin

Androgens

Aldolase

-glucuronidase

Albumin

1,25-Dihydroxyvitamin D3
Calcium binding proteins
Thyroid hormones

Carbamoyl phosphate synthetase

Malic enzymes

Growth hormones

Prolactin

Ecdysone

Dopa decarboxylase

Vitellogenin

Category - General

Query - What processes are stimulated by the hormone below?

Reversal - there is no reversal

Hormone on left, process in center, figure on right

Insulin | Glycolysis Glycogen synthesis Triacylglycerol synthesis Protein, DNA, and RNA synthesis |  | Glucagon | Glycogenolysis Gluconeogenesis Triacylglycerol breakdown |  | Epinephrine | Triacylglycerol breakdown Glycogenolysis |

Category - General

Query - What hormone is produced by the following cell type found in the Islets of Langerhans of the pancreas?

Reversal - there is no reversal

Cell type on left, hormone in center, figure on right

A cells | Glucagon |  | D cells | Somatostatin |  | P cells | Pancreatic hormone |  | B cells | Insulin |