units 21-25 SI and quizzes

You're going hiking and want to pack emergency food in case you get lost or the hike takes longer than you anticipate. Your goal is to pack a food that will have the biggest increase on your blood glucose level to be able to supply your hiking muscles with glucose for cellular respiration. Which of the following foods will lead to the biggest and most immediate increase in blood glucose? -A snack rich in protein, such as a dried meat stick -A snack rich in digestible polysaccharides such as a cooked potato -A snack rich in cellulose, such as a bag of celery -All of these will have equal impacts on blood glucose level -A snack rich in lipids, such as slices of cheese

-A snack rich in digestible polysaccharides such as a cooked potato

Which occurs mainly in the small intestine? -H+ is secreted from epithelial cells into the lumen. -Bile salts are manufactured. -Gastrin is secreted. -Pepsinogen is activated. -Acidic chyme is neutralized.

-Acidic chyme is neutralized.

In which region(s) of the GI tract do peristaltic contractions occur? -The small intestine -The large intestine -The stomach -The esophagus -All of these options are correct.

-All of these options are correct.

Which is NOT stimulated by the hormone insulin? -An increase in glycogen synthesis -An increase in the number of glucose transporters in cell membranes -An increase in triglyceride synthesis -An increase in amino acid uptake by cells -An increase in ketone synthesis

-An increase in ketone synthesis

Which of the following statements regarding hormonal regulation of gastrointestinal function is TRUE? -The hormone somatostatin stimulates the secretion of H+ into the lumen of the stomach. -The presence of fatty acids in the small intestine stimulates the secretion of the hormone secretin, which causes contraction of the gallbladder. -An increase of H+ in the small intestine stimulates secretion of the hormone secretin, which in turn stimulates HCO3- secretion by the pancreas. -The presence of amino acids in the small intestine stimulates secretion of gastrin, which in turn stimulates HCl secretion by parietal cells. -The presence of fatty acids in the stomach stimulates secretion of CCK, which in turn stimulates enzyme secretion by cells in the antrum of the stomach.

-An increase of H+ in the small intestine stimulates secretion of the hormone secretin, which in turn stimulates HCO3- secretion by the pancreas.

Which of these is found in chylomicrons and plasma membranes, and is a precursor for bile salts and steroid hormones? -Cholesterol -Phospholipids -Monoglycerides -Protein -Amino acids

-Cholesterol

Which of the following statements regarding digestion and absorption of carbohydrates is TRUE? -Sucrose is the main form of carbohydrate that can be absorbed by active transport across the intestinal epithelium. -Cellulose from plants is a polymer of glucose that can be easily digested and absorbed by the human GI tract. -Digestible polysaccharides are broken down into the monosaccharides glucose, galactose, and fructose, which can be absorbed. -Carbohydrate digestion begins in the stomach. -Lactose intolerance results from an insufficiency of the enzyme amylase.

-Digestible polysaccharides are broken down into the monosaccharides glucose, galactose, and fructose, which can be absorbed.

Which of the these events follows the absorption of glucose? -Glucose is stored as glycogen in adipose tissue. -Glucose is converted to fat in the liver. -Glucose is stored as fat in skeletal muscle. -Glucose is converted to amino acids in the muscles. -Glucose is used to make energy by only the brain.

-Glucose is converted to fat in the liver.

Which is TRUE regarding the secretion of HCl in the stomach? -H+ diffuses passively from mucosal epithelial cells into the lumen of the stomach, following Cl-. -H+ is actively transported into the gastric lumen by ATPase pumps in the mucosal membrane. -Cl- and HCO3- are exchanged across the luminal membrane of epithelial cells via a passive transport protein. -H+ is actively cotransported into the lumen by secondary active transporters coupled to K+. -The pH of the blood leaving the area of the parietal cells is lower than the normal ECF value of 7.4.

-H+ is actively transported into the gastric lumen by ATPase pumps in the mucosal membrane.

In Addison's disease, the adrenal cortices degenerate. Which will result if a patient with this disease undergoes prolonged fasting? -Excessive liver gluconeogenesis -Hyperglycemia -Decreased insulin sensitivity -Hypoglycemia -Excessive lipolysis

-Hypoglycemia

Which event occurs during exercise but NOT during fasting? -Increased cortisol secretion -Increased breakdown of triglycerides -Increased glucose uptake by muscle -Increased glycogenolysis -Increased fatty acid oxidation

-Increased glucose uptake by muscle

Sarah is a type 1 diabetic. She recently refilled her prescription, but was given glucagon instead of insulin. After her first glucagon injection, which of the following is likely TRUE? -Increased glycogenolysis in liver -Increased triglyceride synthesis in adipose tissue -Decreased glycogenolysis in muscle -Decreased gluconeogenesis in liver -Increased glucose uptake by muscle cells

-Increased glycogenolysis in liver

You are volunteering at a weight-loss clinic. You're in charge of a station that makes individualized recommendations for increasing daily metabolic rate. Which of the following lifestyle changes can increase metabolic rate to the greatest extent? -Increasing blood glucose levels -Increasing dietary caloric intake -Increasing skeletal muscle activity -Increasing mental activity -Increasing environmental temperature

-Increasing skeletal muscle activity

Which correctly describes an action of the hormone insulin? -It is required for the uptake and utilization of glucose by nervous tissue. -It stimulates the breakdown of glycogen in the liver. -It decreases the uptake of amino acids by muscle cells. -It inhibits the action of lipoprotein lipase in the capillaries of adipose tissue. -It increases the uptake and utilization of glucose by muscle and adipose tissue cells.

-It increases the uptake and utilization of glucose by muscle and adipose tissue cells.

A group of students has declared a hunger strike to protest a perception of low-quality dorm food. Jose is one of the protesting students and he has not eaten for three days. Which of the following is likely TRUE of Jose's physiological state? -The secretion of insulin, glucagon, ACTH, and cortisol are all increased. -Muscle protein is broken down to provide substrates for hepatic and renal gluconeogenesis. -The secretion of insulin, glucagon, ACTH, and cortisol are all decreased. -The secretion of insulin and cortisol are increased, while glucagon and ACTH secretion are decreased. -Brain metabolism has shifted to increase utilization of glucose and to decrease oxidation of ketones.

-Muscle protein is broken down to provide substrates for hepatic and renal gluconeogenesis.

Which of the following pathways is activated during the cephalic phase of gastrointestinal control? -Secretion of cholecystokinin -Parasympathetic nerves to enteric nervous system -Sympathetic nerves to enteric nervous system -Short reflexes between the small intestine and stomach -Secretion of secretin

-Parasympathetic nerves to enteric nervous system

Which of the following would be most likely to cause metabolic alkalosis? -Severe vomiting -Hyperventilation -Strenuous exercise -Severe diarrhea -Hypoventilation

-Severe vomiting

Susan recently had bariatric surgery which removed 85% of her stomach tissue and left her with a much reduced stomach volume. Which of the following is TRUE of Susan post-surgery? -She is not able to completely digest proteins and amino acids. -She will be able to store less ingested foods and will require smaller, more frequent meals. -Her chyme will tend to become more acidic than before the surgery. -She will have a reduced ability to absorb water from her meals. -She will have a reduced ability to form her food into a bolus.

-She will be able to store less ingested foods and will require smaller, more frequent meals.

Which is TRUE regarding chylomicrons? -They are too large to enter lacteals. -They readily cross the plasma membrane of adipocytes. -They are converted to monoglycerides and fatty acids by an enzyme inside muscle cells. -They are formed in the lumen of the GI tract by the action of bile salts. -They are converted to monoglycerides and fatty acids by an enzyme found inside capillaries.

-They are converted to monoglycerides and fatty acids by an enzyme found inside capillaries.

If more calories are ingested in food than are expended by metabolism -a person will lose weight. -a person will gain weight. -whether weight is gained or lost depends upon whether the calories are in the form of proteins, carbohydrates, or fat. -a person will stay the same weight because the excess energy is destroyed.

-a person will gain weight.

During the absorptive state of metabolism, amino acids -are mobilized from muscle and other tissues faster than they are taken up by those tissues. -are used for glycogen synthesis in the liver. -are used for protein synthesis in most body cells. -are burned as fuel in muscles, creating urea as a waste product. -may be converted to ketones in the liver.

-are used for protein synthesis in most body cells.

A person who has hypothyroidism would be expected to -have an increased basal metabolic rate. -be restless and irritable. -lose body weight. -have reduced tolerance for cold temperatures. -have symptoms similar to over-activation of the sympathetic nervous system.

-have reduced tolerance for cold temperatures.

You are a pediatrician. You have a young patient who does not seem to be growing. You suspect that there might be stress in the home. You decide to perform a blood test for cortisol and expect to find -None of these answers are correct. -high plasma cortisol levels have led to a decrease in available fuel in the bloodstream. -high plasma cortisol levels have led to an increased skeletal muscle metabolic rate, -there are no nutrients left for growth. -high plasma cortisol levels have led to overall state of catabolism. -high plasma cortisol levels have led to a decrease in blood calcium levels.

-high plasma cortisol levels have led to overall state of catabolism.

Gluconeogenesis is stimulated by decreased levels of -growth hormone. -epinephrine. -glucocorticoids. -glucagon. -insulin.

-insulin.

Lactose intolerance -results from the inability to secrete insulin. -is most common in very young children. -results from removal of the gallbladder. -is an inability to digest proteins. -is an inability to digest milk sugar.

-is an inability to digest milk sugar.

The enzyme lactase -promotes the formation of and storage of bile by the gallbladder. -is involved directly in the digestion of proteins. -is necessary for the breakdown of milk fats. -is embedded in the luminal plasma membranes of intestinal epithelial cells. -is overproduced and released by secretory cells in the small intestine in the condition known as lactose intolerance.

-is embedded in the luminal plasma membranes of intestinal epithelial cells.

Endogenous pyrogen -is released by the pyloric region of the stomach and raises the temperature of digestion. -is released by infection-fighting leukocytes and has the same action as aspirin. -is released by infection-fighting leukocytes and acts on muscle tissue. -is released by infection-fighting leukocytes and acts on the temperature-integrating centers of the hypothalamus. -is released by the hypothalamus and acts on infection-fighting leukocytes.

-is released by infection-fighting leukocytes and acts on the temperature-integrating centers of the hypothalamus.

The small intestine... -is the main site of fat digestion. -secretes amylase, lipase, and various proteases from its epithelial cells. -is the main site of gastrin secretion. -absorbs a larger volume of fluid than any other region of the GI tract -undergoes only peristaltic contractions, both -during the digestion of meals and between meals.

-is the main site of fat digestion. -absorbs a larger volume of fluid than any other region of the GI tract

Excess absorbed glucose is initially converted to triacylglycerides and very low-density lipoprotein by -liver cells. -muscle cells. -adipose cells. -intestinal mucosa cells. -lymphoid cells.

-liver cells.

During the postabsorptive phase of metabolism -glycogen in muscle cells is broken down to glucose, which is released into the blood. -the liver exports lactate to the muscles, which use it for fuel. -triacylglycerols in adipose tissue are broken down to glucose by lipolysis. -liver glycogen is broken down to glucose, which is released into the blood. -glycerol and fatty acids are rapidly assembled into triglycerides in adipose tissue.

-liver glycogen is broken down to glucose, which is released into the blood.

Segmentation of the small intestine -are peristaltic movements that sweep undigestible materials out of the small intestine between meals. -functions mainly to prevent any forward movement of chyme, so that all digestion and absorption is complete before undigestible materials move into the jejunum. -mixes chyme with digestive enzymes, brings food molecules near the wall for absorption, and slowly moves small intestine contents toward the cecum. -occurs only between meals, and functions to stimulate the secretion of gastrin and the resulting mass movements that empty the large intestine. -occurs at a rate of 3 contractions per minute throughout the small intestine, although the strength of contractions is much greater in the ileum, which has a much thicker layer of smooth muscle in its walls.

-mixes chyme with digestive enzymes, brings food molecules near the wall for absorption, and slowly moves small intestine contents toward the cecum.

A person's lowest metabolic rate -occurs during exercise. -occurs after a meal. -occurs when they are younger. -occurs during sleep. -occurs when body temperature increases.

-occurs during sleep.

The subjective feeling of hunger is stimulated when -plasma glucose concentration increases. -plasma ghrelin concentration decreases. -plasma insulin concentration increases. -plasma leptin concentration decreases. -body temperature increases.

-plasma leptin concentration decreases.

The principal means of increasing heat production in response to a cold environment is -vasoconstriction of blood vessels in the skin. -shivering thermogenesis and increased voluntary activity. -vasodilation of blood vessels in skin. -wearing warm clothing. -increasing food intake to elevate the metabolic rate.

-shivering thermogenesis and increased voluntary activity.

The major metabolic effects of glucagon include -stimulating glucose uptake into skeletal muscle cells. -stimulating triglyceride synthesis in adipose tissue. -stimulating the activity of glycogen synthase in the liver. -inhibiting the enzyme glycogen phosphorylase in the liver. -stimulating glycogenolysis and gluconeogenesis in the liver.

-stimulating glycogenolysis and gluconeogenesis in the liver.

With regard to fat metabolism, insulin increases -the activity of lipoprotein lipase, which leads to increased triglyceride synthesis. -the export of fatty acids and monoglyceride from adipocytes. -the activity of hormone-sensitive lipase, which synthesizes triglycerides. -the activity of hormone-sensitive lipase, which catabolizes triglycerides.

-the activity of lipoprotein lipase, which leads to increased triglyceride synthesis.

The thermoneutral zone is defined as -the environmental temperature range in which shivering, changes in blood flow, and changes in thyroid hormone concentrations can maintain homeostasis of the body's core temperature. -the core body temperature at which no energy is expended to maintain homeostasis. -the region in the central core of the body where temperature never changes. -the environmental temperature range over which the changes in skin blood flow alone can regulate body temperature. -the region of the body halfway between the high-temperature core and the low-temperature skin.

-the environmental temperature range over which the changes in skin blood flow alone can regulate body temperature.

You are working for an educational video company and you've been asked to go to the hospital imaging center to obtain video of segmentation. The imaging center technician asks you where in the GI tract she should image and when during digestion? You tell her that to obtain the best video of segmentation she should record -the large intestine during fecal compaction. -the small intestine as chyme moves past the pyloric sphincter. -the esophagus during swallowing. -the stomach during digestion of a meal.

-the small intestine as chyme moves past the pyloric sphincter.

List the three functions of thyroid peroxidase.

1. Oxidation of I- to I2 2. Organification of I2 3. Coupling reaction

List the 4 ways in which thyroid hormone affects BMR.

1. ↑Na+/K+ ATPase 2. ↑ O2 consumption 3. ↑ Heat production 4. ↑ BMR

Typical BMR = ____ kcal per hour

100

The maximal number of amino acids in a peptide that are absorbed is ___.

3

500 kcalories will keep you alive for approximately ____ hours at a typical BMR.

5

Why is, in many ways, giving insulin to a type 2 diabetic a short-term solution?

A complicated issue for sure. In type 2 diabetes mellitus (T2DM), insulin is produced on a typically ideal scale but the problem is that the cells of the body do not respond to the insulin adequately and therefore blood glucose levels remain high. Giving additional insulin can force the cells to take in glucose; however, it does not fix the problem that hyperinsulinemia leads to de novo lipogenesis, fatty liver disease, and worsening insulin resistance.

Anders is born with a mutation in the gene for CCK and he produces and secretes an inactive form of this hormone. Which of the following would be TRUE of Anders' digestion? A reduction in the release of HCl None of these would occur An increase in the amount of bile salts present in the bile A reduction in the release of pancreatic enzymes An increase in the release of bile

A reduction in the release of pancreatic enzymes

The input of water to the digestive tract includes (check all that apply) A. Drinking B. Secretion C. Absorption D. Reabsorption E. Chemical digestion

A. Drinking B. Secretion

Absorptive state's role in affecting metabolic rate.

Absorptive state → "Diet induced thermogenesis" ensues following a meal. Increased metabolic activity consumes more energy

The energy-making pathways involving glucose, ketones, and fatty acids all produce which molecule in common before the Krebs/TCA/citric acid cycle?

Acetyl co-enzyme A

Sort the following into either the insulin-release agonists or insulin-release antagonists categories: epinephrine, norepinephrine, acetylcholine, glucagon, glucose, amino acids, exercise, gastric inhibitory peptide (GIP), growth hormone (GH), cortisol.

Agonists: glucose, amino acids, GIP, acetylcholine... anything that is parasympathetic (Ach); anything that includes nutrients for the body that need to be brought into cells (glucose, AAs); just know GIP independently. Antagonists: epinephrine, norepinephrine, glucagon, cortisol, GH, exercise... anything that is sympathetic (epi and norepi); anything that is indicative of the post-absorptive state (exercise, GH needed for growth); glucagon is insulin's arch-enemy (in most cases); cortisol released in time of stress or fasting so serves to increase to increase glucose concentration in the blood.

Sarah has been diagnosed with pancreatic cancer. The first treatment is to remove 90% of her pancreatic tissue surgically. Due to the loss of exocrine tissue, which of the following foods will Sarah have more difficulty digesting post-surgery? - Starches -Proteins and peptides -Lipids -All of these

All of these

Name 4 enzymes that break apart carbohydrates.

Amylase, Sucrase, Lactase, Maltase

Where are enzymes that break apart carbohydrates found?

Amylase: Saliva and pancreas; Sucrase, Lactase and Maltase: Brush Border

The flow of the enterohepatic portal system in the digestive tract is: __________→__________→________→________→________

Arteries→ Capillary #1 → Vein (including hepatic portal vein)→Capillary #2→Vein

One type of drug used to prevent and treat atherosclerosis (hardening and narrowing of the arteries) acts to prevent bile from getting recycled. How might this processes be related?

Atherosclerosis is caused by many factors but its chances are increased with high fat consumption (i.e. high cholesterol and high LDLs). If you remember back, bile is made of a lot of stuff including bile salts, phospholipids, salts, electrolytes, and cholesterol. Normally, bile is recycled so that the liver does not have to produce as much. By eliminating the recycling process, the liver must take more of the above components (notably cholesterol) from the blood and combine them into bile. Now less cholesterol in the blood à decreased chance of atherosclerosis.

Following diagnosis with pancreatic cancer, Neil had a large portion of his pancreas removed. All of the following will now be found in lower amounts in Neil's GI tract, except one. Which of the following will NOT be affected? -Lipase -Amylase -Bile salts -Trypsinogen -Bicarbonate ions

Bile salts

The enterohepatic circulation describes the secretion and subsequent reabsorption of

Bile salts/acids

Does the pancreas has exocrine or endocrine function?

Both. Endocrine via insulin and glucagon secretion into the blood. Exocrine via secretion of bicarbonate, trypsin, and other digestive enzymes into ducts which enter the small intestine at the sphincter of Oddi.

Which GI hormone inhibits stomach H⁺ production, stimulates HCO₃⁻ production (pancreas)?

CCK

What is CCK's effect on the pancreas?

CCK stimulates release of pancreatic enzymes

Motility of the stomach is limited by ___ and the "____ reflex."

CCK, enterogastric

What is each of the following macromolecules' corresponding product of digestion? Carbohydrates/Polysaccharides/Disaccharides Proteins/Polypeptides Triglycerides

Carbohydrates/Polysaccharides/Disaccharides → Monosaccharides Proteins/Polypeptides → Amino Acids Triglycerides → Monoglycerides

Fill in the following flowchart to explain how Cholera causes diarrhea. Cholera Toxin → ____(g-protein)→____(ion)→____(ion)→Water

Cholera Toxin →ɑs (g protein)→Cl- (ion)→Na+ (ion)→Water

________ is where the precursors to thyroid hormone are stored.

Colloid

Which is caused by increased levels of the hormone cholecystokinin? -Secretion of HCO3- from the pancreatic duct cells -Secretion of gastric H+ -Contraction of the gallbladder -Contraction of the sphincter of Oddi -Inhibition of pancreatic enzyme secretion

Contraction of the gallbladder

_________ _________ __________ allow cooling of the body and are stimulated by the _________nervous system.

Eccrine sweat glands, sympathetic

Energy in vs. Energy out

Energy In Carbohydrates (4 C/gram) Protein (4 C/gram) Triglyceride (9 C/gram) Energy Out Heat (60%) ATP consumption (40%)

Environmental temperature's role in affecting metabolic rate.

Environmental temperature → the environment either adds or subtracts heat from the body, requiring adjustments to body temperature

What types of enzymes are on the brush border?

Enzymes that digest disaccharides & peptides

Epinephrine's role in affecting metabolic rate.

Epinephrine → stimulates catabolism of glycogen, triglycerides

What are the three layers contained within the mucosa?

Epithelium, lamina propria, muscularis mucosa

Which of the following activities is unique to the liver? A. Lipogenesis B. Export of glucose C. Glycogenolysis D. Glycogenesis

Export of glucose

True or False. Macromolecules can be absorbed directly.

FALSE

True or false. The long reflex works independently from the CNS.

FALSE

True or false. Thyroid peroxidase is located on the basolateral side of the epithelial cells.

FALSE - it's on the apical side

During the absorptive state, the body makes use of stored nutrients for energy.

False

Which of the following processes is NOT associated with gastrointestinal function? -Filtration -Secretion -Absorption -Digestion -Motility

Filtration

Which GI hormone stimulates insulin secretion?

GIP

Which GI hormone acidifies the stomach, promotes motility in the stomach, small & large intestine

Gastrin

________ is sensitive to the lack of stretch of the stomach.

Ghrelin

What is glycerol? What is glycogen?

Glycerol is one of the components of a triglyceride and is combined with three fatty acids during lipogenesis. Glycogen is a giant aggregate of glucose monomers. It is a vital source of energy storage in mammals.

Which results from insulin binding to its receptor in skeletal muscle plasma membranes? -Lipoprotein lipase is inhibited. -Protein catabolism is stimulated. -Glycogen phosphorylase is stimulated. -Glucose transport into the cell is inhibited. -Glycogen synthase is stimulated.

Glycogen synthase is stimulated.

If glucose is dangerously low, which will the brain prefer for energy: lipolysis à ATP; glycogenolysis?

Glycogenolysis. The brain hates fats. Can't utilize them for energy. Must have glucose!! Ketones work too.

A goiter would result from which of these conditions? A. Graves disease B. Hypersecretion of TSH C. Insensitivity of TSH receptors D. Oversecretion of TRH E. Insensitivity of TRH receptors F. Oversecretion of T3

Graves disease Hypersecretion of TSH Oversecretion of TRH

What are the major components of bile?

HCO₃⁻, cholesterol, bile pigments, bile salts

Sarah is a type 1 diabetic who forgot to bring insulin with her today. Which of the following will be TRUE of Sarah? -Her liver will not breakdown glycogen. -None of these will occur. -Her muscle cells will not be able to take up as many amino acids from the bloodstream. -Her brain cells will not be able to take up as much glucose from the bloodstream. -Her muscle and adipose tissue cells will not be able to take up as much glucose from the bloodstream.

Her muscle and adipose tissue cells will not be able to take up as much glucose from the bloodstream.

Can you think of a couple cases where beta oxidation would be utilized over glycolysis?

High fat diet --> if not enough glucose available, the body will do what it can and make ATP from fat. Someone with diabetes mellitus --> if insulin is not working or is not present in adequate amounts, glucose cannot enter cells for energy production and therefore fats might be utilized.

The pH of the veins from the stomach is ___, and the pH of the veins from the pancreas is ___.

High, low

Considering the insulin receptor design/mechanism, is insulin likely a hydrophobic or hydrophilic compound?

Hydrophilic. Hydrophobic hormones, like testosterone or aldosterone, can diffuse through the cell membrane because the membrane is filled with phospholipids which are also hydrophobic. They then bind intracellular receptors, usually bound to the nucleus. Since insulin binds an external cell receptor, it suggests that it is hydrophilic and therefore cannot readily diffuse through the cell membrane.

Talia is a busy store clerk on Black Friday. She ate breakfast at 7 am but was not able to take a lunch break because the store was too busy. -Its now 3 pm and she's beginning to feel a bit odd. Which of the following does NOT describe Talia's physiological state? -Hyperglycemia is occurring. -Glucagon secretion is higher than in the absorptive state. -Glucose-sparing reactions are occurring. - Insulin secretion is lower than in the absorptive state. -Gluconeogenesis is occurring.

Hyperglycemia is occurring.

What two cellular activities explain why H⁺ and HCO₃⁻ are continuously formed in the parietal cell?

H⁺ is exported to the lumen and HCO₃⁻ is exported to the blood; this makes these ions very low intracellularly and makes the reaction highly favorable.

What is the primary active transporter responsible for the low pH of the stomach lumen? What paracrine factor has a role in stimulating it's activity?

H⁺/ K⁺ ATPase (counter transporter), Histamine

Which of these targets of T3 is nearly universal, happening in every cell of the body? A. Stimulation of adrenergic receptors B. Increased expression of the Na+/K+ ATPase pump C. Increased consumption of CO2 D. Stimulation of lipolysis E. Stimulation of gluconeogenesis

Increased expression of the Na+/K+ ATPase pump

During the postabsorptive state, what happens to the blood levels of insulin and glucagon? A. Insulin and glucagon both increase. B. Insulin and glucagon both decrease. C. Insulin increases, whereas blood levels of glucagon decrease. D. Insulin decreases, whereas blood levels of glucagon increase. E. Glucagon increases, whereas insulin levels do not change.

Insulin decreases, whereas blood levels of glucagon increase.

What's the relationship between size and density of lipoproteins?

Inverse. HDLs are the smallest, but most dense lipoprotein. Chylomicrons are the largest but least dense.

What happens to T4 once it enters a target cell?

It is converted to T3 by iodinase and then used to activate intracellular receptors

In what way is the Cl-/K+/Na+ transporter on intestinal cells different from kidney cells?

It is located on the basolateral side of the cell

A person with type 1 diabetes mellitus comes into the hospital with hyperglycemia (high blood glucose). What would their relative levels of C-peptide be before and after IV insulin administration?

It would be about the same before and after IV insulin. C-peptide is produced in a 1:1 ratio with synthesized insulin. If the patient is hyperglycemic, their insulin amount, and therefore C-peptide amount, would be low. Receiving insulin does not change the amount of C-peptide.

________ is a polypeptide hormone synthesized by adipocytes and released from cells in proportion to the amount of fat they contain.

Leptin

_______ is the "full hormone" (long term) and ________ is the "hunger hormone" (short term).

Leptin Ghrelin

Name 1 enzyme that breaks apart triglyceride.

Lipase

The pH of the stomach lumen is ___, and the pH of the pancreatic ducts is ___.

Low, high

Starches are broken down into _____, _____, and _____.

Maltose, maltotriose, limit dextrans

Where is serous fluid secreted?

Mesothelium

________ __________ _____________ __________ is an essential immune system component of the mucosa.

Mucosa - associated lymphatic tissue (MALT)

Muscle activity's role in affecting metabolic rate.

Muscle activity → huge amounts of ATP consumption require replacement of ATP and breakdown of glycogen, fatty acids, and/or ketones

____________ __________ controls peristalsis and other contractions of muscularis externa.

Myenteric plexus

How is iodine drawn into cells?

Na⁺/I- Symporter (NIS) draws I- into cells (secondary active transport)

What is the function of the appendix?

One of the leading theories is that it serves as a reservoir for "healthy" bacteria that can help re-populate the intestines after a bacteria-altering illness.

Insulin is secreted in response to elevated blood glucose, and it's effect is to lower blood glucose. Why might you expect a stronger insulin response to oral glucose than to intravenous glucose of the same quantity?

Oral glucose will stimulate GIP release, which will enhance glucose's effect on insulin secretion

Where is the enzyme that breaks apart triglycerides found?

Oral mucosa and Pancreas

What structure secretes the enzyme that breaks down starch to smaller carbohydrates? -The esophagus -The liver -The large intestine -Pancreatic duct cells -Pancreatic exocrine cells

Pancreatic exocrine cells

What is the main digestive enzyme in the stomach?

Pepsin

Name 5 enzymes that break apart proteins.

Pepsin, Trypsin, Chymotrypsin, Carboxypeptidase, Aminopeptidase

Where are the enzymes that break apart proteins found?

Pepsin: Stomach; Trypsin and Chymotrypsin: Pancreas; Carboxypeptidase and Aminopeptidase: Brush Border

Rhythmic smooth muscular contractions that help move content through the intestines and expel feces: ___________.

Peristalsis

Why is cortisol known as permissive? Why may stress lead to the worsening of type 2 diabetes?

Permissiveness is when one substance (i.e. cortisol) is required for another substance (i.e. GH) to exert its full effects. Cortisol also makes cells less sensitive to insulin, resulting in a potentially greater effect of all post-absorptive compounds like epi, norepi, and glucagon. In T2DM, the cells are already less sensitive to insulin so the release of cortisol (stimulated by stress), may exacerbate the problem.

What is their corresponding digestive enzyme? Polysaccharides Proteins Triglycerides

Polysaccharides → Amylase Proteins → Protease Triglycerides → Lipase

A patient comes in to the hospital and is found to be hyperglycemic and hypokalemic (low potassium). Should you give insulin?

Probably not. Insulin will lower the blood glucose by bringing it into the cell. But it will also bring potassium into the cell with it (indirectly via the sodium/potassium ATPase pump), thus exacerbating the already low potassium in the blood. What is usually done instead is the patient is given slow-drip insulin while also receiving potassium supplementation.

In peristalsis, stretch of the intestines results in _____ of smooth muscle in front of the bolus and _____ of smooth muscle behind the bolus.

Relaxation, contraction

Which GI hormone inhibits stomach H⁺ production, stimulates enzyme production (pancreas) and gall bladder contraction?

Secretin

What is the outermost layer of the connective tissue in the GI tract wall?

Serosa or visceral peritoneum

Fill in the flow chart. Smell of food →_________ phase→__________ phase→_________phase

Smell of food →cephalic phase→gastric phase→intestinal phase

In the absorptive state, which of the following would most likely be occurring: glycolysis, glycogenolysis, gluconeogenesis, glycogenesis, beta oxidation, de novo lipogenesis?

Some glycolysis may be occurring as glucose enters the cell and is indirectly converted into ATP for energy. Glycogenolysis would not be occurring because the body recently ate and does not need to break down glycogen for more glucose at the moment. Gluconeogenesis would not be occurring for the same reason; don't need new glucose right now. Glycogenesis would certainly be occurring because we would be storing some of the newly consumed glucose into glycogen for use later. Like glycolysis, beta oxidation may occur as fats enter cells and are oxidized to make ATP. De novo lipogenesis would occur as some excess glucose is converted to fat for storage.

CCK causes relaxation of _____ and contraction of _____.

Sphincter of Oddi, Gall bladder

____________ __________ controls glandular secretion of mucosa.

Submucosal plexus

TBG binds ____ and _____ while albumen binds only ____.

TBG binds T3 and T4 while albumen binds only T4.

What hormone does the hypothalamus secrete in response to a low body temperature?

TRH

TRH-neuron of hypothalamus → _____→ ________ ________ (thyrotroph) → ______→ ________ ______ of thyroid gland → T3/T4 production

TRH-neuron of hypothalamus → TRH → anterior pituitary (thyrotroph) → TSH → follicle cells of thyroid gland → T3/T4 production

_____ stimulates endocytosis of thyroglobulin.

TSH

__________ ____________is the major hormone for controlling body temperature.

Thyroid hormone

Thyroid hormone (T3)'s role in affecting metabolic rate.

Thyroid hormone (T3) → increases BMR through activation of Na+/K+ ATPase pump and catabolic enzymes (action includes heat production)

__________ -______________ ________________ is a protein produced that mimics TSH and activates T3/T4 (seen in graves disease).

Thyroid-stimulating immunoglobulin

Cholera toxin, the toxin released by the bacteria that cause cholera disease, interferes with water absorption and causes water secretion into the gastrointestinal tract. Even in the absence of bacteria, this toxin can cause diarrhea. True or false

True

During cholera infection, which causes severe diarrhea, the primary acute danger to one's health is dehydration. In terms of water balance, this is due to the loss of fluids added to the GI tract more than due to a decreased volume of ingested fluids. True or False

True

During the absorptive state, there is net synthesis of fat, glycogen, and protein, but this process is reversed during the postabsorptive state.

True

Food mixed with digestive juices in the stomach is called chyme. True or False

True

Receptors for the regulation of body temperature are heat and cold receptors in the skin, the CNS, and internal organs. True or false

True

The body's most effective mechanism for reducing heat loss is vasoconstriction of blood vessels in the skin. True or false

True

The lumen of the gastrointestinal tract is continuous with the external environment. True or False

True

The volume of fluids secreted by the gastrointestinal tract in a typical day is far greater than the volume of food and drink ingested. True or false

True

True or false. T3 serves as a negative feedback for TRH.

True

Most zymogens are activated by they enzyme _____, which is activated by _____.

Trypsin, enterokinase

_____ units of oxygen are used to convert 1 unit of glucose into _____ units of pyruvate?

__0__ units of oxygen are used to convert 1 unit of glucose into __2__ units of pyruvate. Glycolysis is an anaerobic process and does not require oxygen. Glucose is a 6-carbon molecule and pyruvate is a 3-carbon molecule. Each glucose makes two pyruvates.

During the absorptive state, where is de novo lipogenesis occurring? Check all that a. apply A. adipocytes B. liver C. muscle cells D. brain E. all cells of the body

adipocytes and liver

Glucagon is secreted from ________ cells of the pancreas and stimulates ________ of macromolecules. A. alpha : anabolism B. beta : anabolism C. delta : anabolism D. alpha : catabolism E. beta : catabolism

alpha : catabolism

Once the products of triglyceride digestion have entered the epithelial cells that line the small intestines, they A. cross the basolateral membrane and enter the circulation where they will be embedded into a chylomicron. B. are reassembled into triglycerides and released into the blood where they can be incorporated into chylomicrons. C. are reassembled into triglycerides and packaged by the Golgi apparatus into micelles. D. are reassembled into triglycerides and packaged by the Golgi apparatus into chylomicrons. E. are further degraded to glucose, and then incorporated in to micelles.

are reassembled into triglycerides and packaged by the Golgi apparatus into chylomicrons.

The ________ ____________ _______ is sometimes referred to as the "metabolic cost of living".

basal metabolic rate

he Na⁺/I- symporter is important to thyroid hormone production because it moves I- across the A. basolateral membrane into the cell B. apical membrane into the cell C. basolateral membrane into the colloid D. apical membrane into the colloid

basolateral membrane into the cell

In the synthesis of _____, both enzymes of the liver and those of bacteria are necessary.

bile acids / bile salts

What degradation by-product of hemoglobin is removed from the blood by the liver and then secreted into the bile? A. phospholipids & cholesterol B. bile pigments C. iron D. urea E. uric acid

bile pigments

Which of the following does NOT influence cortisol secretion? A. physical stress B. circadian rhythm/diurnal cycle C. mental stress D. blood amino acid concentrations

blood amino acid concentrations

One _________ is the amount of heat required to raise 1 gram (ml) of water 1 ℃.

calorie

A person without a gallbladder -cannot secrete bile. -will have no difficulty digesting a large, fat-rich meal. -cannot digest fats. -cannot store lipase. -cannot store bile.

cannot store bile.

Ketones are NOT produced from A. carbohydrates B. proteins C. lipids

carbohydrates

The _____________ __________ is when the brain prepares the stomach for the arrival of food.

cephalic phase

_______ is the mixture of ingested food particles and gastric secretions.

chyme

Which of the following is an effect of elevated blood-insulin levels? A. increased blood-glucose B. decreased blood-amino acids C. decreased intracellular glucose D. increased lipolysis E. decreased intracellular amino acids

decreased blood-amino acids

The pancreas responds to CCK by secreting

digestive enzymes

You go see a scary movie. By the end of the movie your heart is racing thanks to high levels of epinephrine in your bloodstream. You ate nothing during the movie, but your blood glucose level is likely -elevated due to the pasta meal consumed at home before the movie. -low due to the action of cortisol on blood glucose regulation. -elevated due to healthy post-absorptive state mechanisms. -low due to an overall lack of nutrients. -elevated due to the action of epinephrine on blood glucose regulation.

elevated due to the action of epinephrine on blood glucose regulation.

The GI tract has its own local control, a division of the autonomic nervous system known as the ___________ __________ _____________.

enteric nervous system.

Secretion is the movement of molecules from the _________ to the_________.

from the blood to the lumen

Absorption is the movement of molecules from the _________ to the ________.

from the lumen to the blood

Lactase is needed to break down lactose into _____. A. glucose & fructose B. glucose & maltose C. galactose & maltose D. galactose & fructose E. galactose & glucose

galactose & glucose

During the absorptive state cells are primarily using _____ for fuel.

glucose

In the liver, gluconeogenesis produces glucose from _____ and from glucogenic amino acids.

glycerol / pyruvate

Sweat is ______________.

hypoosmotic

Ghrelin inhibits the _____________ from producing cortisol and T3.

hypothalamus

The primary integrator of body temperature control reflexes is the - medullary cardiovascular center. -cerebral cortex. -hypothalamus. -thyroid gland. -adrenal medulla.

hypothalamus.

Which of the following is NOT consistent with the post-absorptive state? A. increased triglyceride synthesis B. increased glycogenolysis C. increased gluconeogenesis D. increased ketone synthesis

increased triglyceride synthesis

When plasma glucose concentration increases, the secretion of insulin is __________ and the secretion of glucagon is __________. An increase in sympathetic activity will cause __________ secretion of insulin and __________ secretion of glucagon. increased; increased; decreased; increased decreased; increased; increased; decreased decreased; decreased; increased; unchanged increased; decreased; decreased; increased increased; decreased; increased; decreased

increased; decreased; decreased; increased

Cortisol increases plasma glucose concentration in what way? A. increases lipogenesis B. increases gluconeogenesis C. decreases glycolysis D. increases glycolysis E. increases sensitivity of cells to insulin

increases gluconeogenesis

The metabolic adjustments that occur in the body during the switch from postabsorptive to absorptive state are largely triggered by increases in what hormone? A. insulin B. glucagon C. thyroid hormone D. epinephrine E. cortisol

insulin

When T4 enters cells it A. binds to the thyroid hormone receptor and activates transcription B. binds to the thyroid hormone receptor and phosphorylates intracellular targets C. is converted to T3 by an iodinase enzyme D. is converted to MIT and DIT before it becomes active

is converted to T3 by an iodinase enzyme

Bile is synthesized and secreted by the -liver. -duodenum. -pancreas. -gallbladder. -gastric mucosa.

liver

The hepatic portal system involves two capillary beds in series. The first is found in the submucosa of the digestive tract and the second is found in the... [Blank]

liver / sinusoids

Where does most lipid digestion take place? A. saliva B. stomach C. lumen of small intestines D. lumen of large intestines E. in the pancreas

lumen of the small intestine

___________ digestion is when food is broken down through physically into smaller pieces whereas __________ digestion is when food is broken down by chemicals.

mechanical chemical

Triglycerides are converted to _____ and free fatty acids by the digestive processes within the intestinal lumen.

monoglycerides

A low environmental temperature will burn more/less calories than a high environmental temperature.

more

The myenteric plexus is found within the A. mucosa B. submucosa C. serosa D. muscularis externa

muscularis externa

Where are the enzymes that break down disaccharides located? A. in the lumen of the small intestine B. on the apical membrane of intestinal cells C. inside intestinal cells D. on the basolateral membrane of intestinal cells E. in the lumen of the large intestine

on the apical membrane of intestinal cells

There are two locations of thermoreceptors, one is in the _____ (called _________ thermoreceptors) and the other (called _________ thermoreceptors) in deep body structures.

one is in the skin (called peripheral thermoreceptors) and the other (called central thermoreceptors) in deep body structures

_____________ ____________ is the retention of osmotically active particles in intestines results in inadequate fluid absorption. What is one example of this?

osmotic diarrhea example: Lactose intolerance

The primary motor component of the long reflex pathway typically involves the ________ nervous system, which acts to promote an increase in gastrointestinal activity. A. parasympathetic B. sympathetic C. somatic D. enteric E. intrinsic

parasympathetic

Sarah is taking antacids every day. This habit is raising her stomach and duodenal pH close to neutral. Which of the following enzymes may have decreased activity? -Amylase -Lipase -Chymotrypsin -Trypsin -Pepsin

pepsin

The response of the body to growth hormone (GH) is quite similar to other post-absorptive state hormones. What macromolecule undergoes anabolism under the influence of GH? A. lipid B. protein C. carbohydrate D. nucleic acid

protein

As heat in the body rises, metabolic activity rises/falls.

rises

Cholera toxin produces an "always on" pumping of Cl⁻ ions into the digestive lumen. This results in a type of diarrhea called... [Blank]

secretory diarrhea

____________ ___________ is excessive secretion by intestinal cells. What is one example of this?

secretory diarrhea example: Cholera toxin

The enterogastric reflex that runs from the duodenum to the stomach is an example of a A. hormonal reflex B. long reflex C. short reflex D. knee-jerk reflex

short reflex

The absorption of glucose across the apical membrane of the luminal epithelial cells occurs through which process? A. facilitated diffusion B. diffusion C. sodium-linked secondary active transport D. primary active transport E. paracellular transport

sodium-linked secondary active transport

Which of the following are mechanisms by which cholecystokinin (CCK) facilitates digestion of fats? A. stimulation of lipase activity and bile excretion B. stimulation of gallbladder contraction and relaxation of the sphincter of Oddi C. stimulation of lipase excretion and gallbladder contraction D. stimulation of bile excretion and liver contraction E. stimulation of bile excretion and contraction of the sphincter of Oddi

stimulation of gallbladder contraction and relaxation of the sphincter of Oddi

What stimulates the defecation reflex? A. increase in osmolarity of the rectum B. peristaltic contraction of the sigmoid colon C. negative pressure on the external anal sphincter D. stretching of the wall of the rectum E. stretching of the wall of the descending colon

stretching of the wall of the rectum

Besides absorption of water and ions, what important molecule is absorbed from bacterial activity in the large intestines?

vitamin k

Which of these situations would NOT result in an increased metabolic rate from the basal metabolic rate? A. A warm room temperature B. Running from an angry bear C. Eating a meal D. Lifting weights

warm room temperature

The hypothalamus creates cortisol and T3 in order to ___ the metabolic rate. (↑/↓)

↑

___ TSH stimulates goiter formation.

↑

The production of leptin sends signals to the hypothalamus that indicate a(n) __ in satiety and __ need for food intake. (↑/↓)

↑ in satiety and ↓ need for food intake.

Ghrelin __ metabolic rate. (↑/↓)

↓

The stimulus for secretin is _____ and the response is pancreatic secretion of ___.

↓duodenal pH, HCO₃⁻