The term ‘metabolism’:
refers to all the chemical reactions that occur in the body
includes the synthesis of complex molecules from simpler ones
includes the breakdown of complex molecules into simpler ones
includes anabolism and catabolism
all of the above
Which of the following statements concerning energy storage in the body is true?
most is stored in the form of ATP
most is stored in the form of glucose
most is stored in the form of fat
most is stored in the form of protein
most is stored in the form of DNA
The enzyme amylase is secreted by:
liver and duodenum
duodenum and pancreas
salivary glands and liver
pancreas and salivary glands
stomach and duodenum
An example of absorption is the:
movement of food by peristalsis
active transport of glucose into a villus
hydrolysis of a peptide into amino acids
release of secretin in the presence of HCL
c and d
Chewing food aids digestion by:
stimulating the release of bile
increasing the surface area of the food
breaking up large protein molecules into peptides
breaking down carbohydrates
breaking down fats
A function of the small intestine is to:
secrete bile
filter waste
make vitamins
absorb nutrients
secrete HCL
The main source of energy in food is:
proteins
vitamins
nucleic acids
carbohydrates
lipids
Which of the following has the lowest pH?
gastric juice
hepatic bile
pancreatic juice
saliva
secretion of the intestinal glands
Calcium absorption is facilitated by:
hypercalcaemia
oxalates in the diet
iron overload
1,25-dihydroxycholecalciferol
increased Na+ absorption
When parietal cells are stimulated, they secrete:
HCL and intrinsic factor
HCL and pepsinogen
HCL and HCo3-
HCO3- and intrinsic factor
mucus and pepsinogen
Secretion of HCL by the gastric parietal cells is needed for:
activation of pancreatic lipases
activation of salivary lipases
activation of intrinsic factor
conversion of pepsinogen into pepsin
formation of micelles
Fat absorption occurs mainly in the:
stomach
duodenum
terminal ileum
caecum
sigmoid colon
The movements of the small intestine are:
mixing contraction
propulsive contraction
antiperistaltic contraction
hunger contraction
a and b
Where the protein hydrolysis occurs:
oral cavity
small intestine
esophagus
b, and c
Which of the following organs or tissues is most dependent upon a constant blood supply of glucose?
liver
brain
adipose tissue
skeletal muscle
cardiac muscle
After a fatty meal is taken, most of the fat would be:
absorbed in the portal circulation and transported to the liver
absorbed in the portal vein and transported in the hepatic artery
absorbed as chylomicrons in the lymphatic system
absorbed as triglycerides into the portal vein and bypasses the liver
absorbed in the duodenum
For fat digestion:
bile salts are the most efficient emulsifiers
gastric lipase is the most important
pancreatic lipase in the duodenum is the most important
digestion takes place in micelles
micelles attach to enterocyte receptor
Gastric acid secretion is decreased by:
vagal inhibition
ingestion of protein
noradrenaline
M1-cholinergic antagonist show the same efficacy at reducing gastric acid secretion
distension of bowel wall
Release of which one of the following increases the pH of duodenal contents?
secretin
gastrin
intrinsic factor
cholecystokinin
gastrin releasing peptide
In the small intestine, glucose is absorbed:
passively
by secondary active transport (coupled to Na transport)
by facilitated diffusion
by co-transport with chloride
actively by insulin dependent uptake
After ingestion of a meal:
digestion of fat and carbohydrate begins in the mouth while protein digestion begins in the stomach
carbohydrates are digested in the mouth and proteins in the stomach
proteins are digested in mouth and fats and carbohydrates in stomach
most fluid and electrolytes are absorbed in the large bowel
composition of the food has no effect on transit time through the bowel
Calcium uptake in the intestine:
is passive
requires a carrier protein on the mucosal side
is by facilitated diffusion
is less than 10% of dietary intake
is facilitated by phosphate
Which one of the following is a water soluble vitamin?
vit. A
vit. B
vit. D
vit. E
vit. K
In the duodenum in response to acidic chyme is released:
peptide
amylase
In the GI tract. the layer, responsible for absorption and secretion is:
mucosa
submucosa
muscularis
serosa
adventitia
The digestive enzyme, produced in the salivary glands and the pancreas is:
maltase
pepsin
nuclease
lipase
This keeps the chyme in the stomach until it reaches the right consistency to pass into the small intestine:
esophageal sphincter
Intrinsic sphincter
cardiac sphincter
pyloric sphincter
duodenal sphincter
Most of the chemical and mechanical digestion is carried out within:
pylorus
fundus
large intestine
Parietal cells secrete:
serotonin
mucus
pepsinogen
hydrochloric acid
The cells at the base of fundic or oxyntic glands are:
chief cells
G cells
enteroendocrine cells
goblet cells
parietal cells
The chyme movement and flow into the stomach is controlled by:
nervous system
pancreas
various digestive system hormones
both the nervous system and various digestive system hormones
The function of the ileum is to:
absorb vitamin B12 and bile salts
introduce bile and pancreatic juices
absorb alcohol and aspirin
Gastrointestinal hormones:
are secreted by exocrine glands of the gut mucosa and affect metabolism
are secreted into the blood stream by specialised cells in the gut walls and modulate its motor and secretory activity
are secreted by the gastric walls and protect the gut mucosa from the effect of HCL and proteolytic enzymes
are situated in the epithelial intestinal cells (enterocytes) and control the cell metabolism of nutrients
are secreted by the gastric walls and colon and protect the gut mucosa from the effect of HCL and proteolytic and nucleic enzymes
The gastrointestinal enzymes;
are situated in the epithelial cells (enterocytes) and control cell metabolism
are secreted into the blood stream by specialized cells in the gut walls and modulate its motor and secretory activity
are secreted by exocrine glands of the gut mucosa and break down nutrients
are secreted by the gastric walls into the small intestine and protect the gut mucosa om the effect of HCL, proteolytic and nucleic enzymes
Which enzymes are secreted with the gastric juice:
pepsinogene and lipase
pepsinogene, tripsinogene and maltase
pepsinogene, lipase and HCL
protcolytic, lipolytic and amylolytic enzymes
protcolytic, nucleolytic, lipolytic and amylolytic enzymes
Which enzymes are secreted with the pancreatic juice:
lipolytic: lipase and esterase
proteolytic: trypsinogen, chymotrypsinogen, elastase, carboxypeptidase, etc
amilolitic: amylase, maltase, sacharase, lactase
nucleic: RNA-ase and DNA-ase
The enzymes, secreted with the intestinal juice are:
exopeptidases, lipase, maltase, nucleic (nuclease, nucleotidases, nucleosidases)
endo- and exopeptidases, esterase and amylolytic enzymes
aminopeptidase, dipeptidase, nuclease and llpase
aminopeptidase, dipeptidase, nuclease, somatostatin, secretin, cholecystokinin-pancreozimin
trypsinogen, chymotrypsinogen, elastase and lipase
Which of the bile components are important for digestion:
secretin and hepatocrinin
bile salts, phospholipids, cholesterol
acid phosphatase, secretin and hepatocrinin
proteolytic, lipolytic and amylolytic enzymes
cholecystokinin-pancreozimin and hepatocrinin
The humoral factors inhibiting gastric motility are:
Gastrin
GIP, catecholamines, secretin, somatostatin, cholecystokinin-pancreozimin
Secretin and cholccystokinin-pancreozimin
Gastrin and motilin
Intestinal hormones, somatostatin, secretin and cholecystockinin-pancreozimin
The humoral factors stimulating gastric motility are:
Catecholamines, secretin, gastric peptide, somatostatin, cholecystokinin-pancreozimin
Secretin and cholecystokinim-pancreozimin
Motilin and gastrin
GIP, VlP, somatostalin, secretin and cholecystokinin-pancrezimin
Gastrin, histamine, secretin
The humoral factors that stimulate intestinal motility are:
catecholamines and intestinal hormones
secretin, cholecystokinin-pancreozimin, GlP, VIP, substance P and bombesin
intestinal hormones
gastin, secretin, cholecystokinin-pancreozimin and hepatocrinin
The humoral factor's that inhibit gastric secretion are:
Gastrin, histamme, acetylcholine, cholecystokinin-pancreozinin, bombesin, motilin
Secretin, cholecystokinin-pancreozimin, somatostatin, catecholamines
GIP, secretin, cholecystokinin-pancreozimin, VIP, enterogastrone
Enkephalines, endorphines, angiotensinogens
Corticoglomerolotropin, prolactin, substance P
Which humoral factors stimulate gastric secretion:
Secretin, cholecystokinin-somatostatin
Secretin, cholecystokinin-pancreozimin, histamine, acetylcholine, bombesin,motilin, meat and vegetable extracts
VIP, somatostatin, GIP, cholecystokinin-pancrcosimin
Corticoglomerulotropin, prolactin, substance P
The physiological effect of gastrin on gastric secretion is:
increased amount of gastric juice of low acidity and high proteolytic activity
to decrease the amount of gastric juice
decreased amount of gastric juice of high acidity and low proteolytic activity
increased amount of gastric juice of high acidity and low proteolytic activity
The physiological effect of histamine on gastric secretion is:
to decrease the amount of the gastric juice
increased amount of gastric juice of high acidity and high proteolytic activity
The humoral factors that stimulate the formation and secretion of bile are:
angiotensin, thyroxine, somatostatin
glucagon, calcitonin, VIP
secretin, gastrin, cholecystokinin-pancreozimin, bile salts
catecholamines, glucagon, calcitonin, VIP
alkaline and acid phosphatase
The humoral factors that inhibit the formation and secretion of bile are:
secretin, gastrin, cholecystokinin-pancreozimin, acetylcholine
catecholamines, no
angiotensin, tiroxin, somatostatin
insulin, glucagon, cathecholamines, growth hormone, glucocorticoids, thyroid hormones
The humoral factors that stimulate the secretion of pancreatic juice are:
glucagon, calcitonin, somatostatin
tripsin, amilase, lipase
secretin, cholecystokinin-pancreozimin, gastrin, serotonin, VlP, insulin
somatostatin, GIP
glucagon, insulin, catecholamines, growth hormone, glucocorticoids, thyroid hormones
The carbohydrates are absorbed as:
mono- and disaccharides
glucose and glycogen
monosaccharides - pentoses and hexoses
glucosamines
glucose, glycogen, glucosamine
The hormones regulating carbohydrate metabolism (synthesis, catabolism) are:
androgenes, estrogenes, progesteron, adrenoglomerulotropin
insulin, glucagon, catecholamines, growth hormone, glucocorticoids (ACTH), T3 and T4 (TTH)
somatostatin, bombesin, gastrin, histanime, kinins
glucagon, calcitonin, somatostatin, calecholamines, serotonin
catecholamines, glucagon, dehydroepiandroserone, somatotropin
The hormones that increase significantly the basic metabolic rate are:
Insulin and glucocorticoids
Glucagon and parathyroid hormone
Testosterone and estrogens
T3, T4, catecholamines and glucocorticoids
Insulin and growth hormone
Glucose enters the blood stream via:
absorption in the mouth
gluconeogenesis in the skeletal muscles
enterocytes' absorption, liver glycogen catabolism, hepatocytes and kidneys gluconeogenesis, renal proximal tubule epitheliocytes
degradation of glycogen in the skeletal muscles
glucogenolisis in the hepatocytes
The basal metabolic rate is the energy consumption of the body under the following conditions:
adequate intake of vitamins regulating the intermediate processes of metabolism of the various substances
normal function of the endocrine glands
physical and psychic rest, 12 hours after the last meal in a room at a temperature of 20-22°C
during physical activity
during sleep, pregnancy or lactation
The chief cells of the stomach glands secrete:
enzymes
gastrointestinal hormones
autonomously active substances
The humoral and pharmacological factors inhibiting salivary secretion are:
catecholamines
cholinolytics
adrenominetics
catecholamines, cholinolytics, adrenomimetics
adrenolytics and cholinomimetics
Humoral factors taking part in the calcium/phosphorus homeostasis are:
parathyroid hormone and thyroxin
parathyroid hormone, thyrocalcitonin and vitamin D3
thyrocalcitonin and epinephrine
thyrocalcitonin and aldosteron
antidiuretic hormone, androgens and angiotensin II
The body requires amino acids to:
produce new red blood cells
produce new protein
replace damaged red blood cells
replace damaged protein
b and d
Which of the following will catalyze the breakdown of starches?
protease
sucrase
peptidase
Which molecule represents the storage form of glucose in the liver?
glycogen
glucagon
disaccharide
lactic acid
carbonic acid
As far as bile is considered:
contains enzymes required for the digestion of fat
contains unconjugated bilirubin
bile salts make cholesterol more water-soluble
pigments contain iron
becomes more alkaline during storage in the gallbladder
Saliva:
from different salivary glands has a similar composition
contains enzymes essential for the digestion of proteins
has less than half the ionic calcium level of plasma
has more than twice the iodide level of plasma
has a pH between 5 and 6
Swallowing is a reflex which:
has its reflex centres in the cervical segments of the spinal cord
is initiated by a voluntary act and includes inhibition of respiration
has its reflex centres in the thoracic segments of the spinal cord
is not dependent on intrinsic nerve networks in the esophagus
is more effective when the person is lying down rather than when standing
Appetite for food is increased:
by the secretion of cholecystokinin
by the secretion of calcitonin
when the stomach is distended
the stomach is denervated
the environment is cold
Secretion of saliva increases when;
atropine is applied
the month is flushed with fluids with a pH of about 7
the subject thinks of unappetizing food
epinephrine is applied
the saliva glands parasympathetic nerve supply is stimulated
Defecation is a reflex action:
that is coordinated by reflex centres in the sacral cord
whose afferent limb carries impulses from stretch receptors in the colon
whose efferent limb travels mainly in sympathetic autonomic nerves
which is more likely to be initiated just before a meal than just after it
which can be unvoluntarily inhibited or facilitated
In the stomach:
pH rarely falls below 4.0
pepsinogen is converted to pepsin by hydrochloric acid
ferrous iron is reduced to ferric iron by hydrochloric acid
acid secretion is inhibited by pentagastrin
there is a rise in the bacterial count after histamine H1 receptor blockade
Intestinal juice contain:
potassium in a concentration similar to that in extracellular fluid
enzymes that are released when the vagus nerve is inhibited
enzymes that hydrolyze disaccharides
enzymes that hydrolyze monosaccharides
enzymes that suppress pancreatic proteolyic enzymes
Pancreatic secretion:
in response to vagal stimulation is copious, rich in bicarbonate but poor in enzymes
in response to acid in the duodenum is scanty but rich in enzymes
to response to secretin secretion is low in bicarbonate
contains enzymes that digest neutral fat to glycerol and fatty acids
contains enzymes that convert disaccharides to monosaccharides
The liver is the principal site for:
synthesis of plasma albumin
synthesis of plasma globulins
synthesis of vitamin B12
storage of vitamin C
activation of some polypeptide hormones
The gastric juice:
is secreted when the vagus nerves are stimulated
is secreted in vagotomized animals when food IS chewed but not swallowed
activates the digestive enzymes secreted with saliva
digests the gastric mucosa because it is not protected by a pepsin inactivator
does not imitate the oesophageal mucosa if regurgitated from the stomach
The respiratory quotient:
is the volume of 02 consumed to the volume of CO2 produced ratio
depends essentially on the type of substrate being metabolized and is 1.0 when the substrate is glucose
is 1.0 in conditions of metabolic alcalosis
is between 0.9 and 1.0 in the second week of fasting
is above 0.8 if fats are mainly metabolized
Oxygen consumption tends to increase when the:
concentration of oxygen in inspired air rises
metabolic rate falls
body temperature rises and environmental temperature falls
environmental temperature increases
before a meal is ingested
Brown fat is:
relatively more abundant in adults than in infants
richer in mitochondria than ordinary fat and has an extensive sympathetic innervation
produces less heat and more ATP than other tissues
stimulated to generate more but when its parasympathetic nerve supply is stimulated
less important than shivering in neonatal thermoregulation
Nitrogen balance:
is the relationship between the body's nitrogen intake and nitrogen loss
is usually negative in childhood
becomes more positive when dietary protein is decreased
becomes positive whenever a single essential amino acid is omitted from the diet
becomes less negative in the final stages of fatal starvation
The normally innervated stomach:
is stimulated to secrete gastric juice when food is chewed, even if it is not swallowed
secrete HCL when its H1- histamine receptors are blocked
increases gastric secretion when there are fear and depression
empties slower than the denervated stomach
is stimulated to secrete gastric juice by the hormone secretin
The passage of acidic gastric contents to the duodenum may cause:
copious secretion of pancreatic juice rich in bicarbonate
increased gastric motility
relaxation of the gallbladder
contraction of the sphincter of Oddi
inhibition of pancreozymin secretion
Bile salts:
derived from cholesterol, are the only constituents of bile necessary for digestion
have a characteristic molecule, being water-soluble
are reabsorbed mainly in the upper small intestine
increase surface tension
are absorbed in the colon
The specific dynamic action of food:
is the decrease in metabolic rate that results from ingestion of food
persists for about an bout after a meal is ingested
is due to the additional energy expended in digesting and absorbing the food
results in about 30 per cent of the may value of ingested protein being unavailable for other purposes
results in about 20 per cent of the energy value of ingested fat and carbohydrate being unavailable for other purposes
Secretion of gastric juice:
decreases when food stimulates mucosal cells in the pyloric region
is associated with a decrease in the pH of venous blood during the stomach
in response to food is increased after vagotomy
is essential for carbohydrate digestion
is essential for absorption of vitamin B12
In the small intestine:
the enzyme concentration in intestinal juice is higher in the ileum than in the jejunum
vitamin B12 is absorbed mainly in the jejunum
water absorption is independent on the active absorption of sodium and glucose
absorption of calcium occurs mainly in the terminal ileum
glucose absorption is dependent on sodium absorption
The cells of the liver:
help to maintain the normal blood glucose level
deaminate amino acids to form NH4+ which is excreted as ammonium salts in the urine
synthesize Vitamin D3 (cholecalciferol)
manufacture most of the immune globulins
activate steroid hormones manufactured in the gonads
Absorption of dietary fat:
can only occur after the neutral fat has been split into glycerol and fatty acids
does not depend on their size
is impaired when bile salt reabsorption is prevented by resection of the terminal ileum
is carried out by passive diffusion
is greatest in the lower parts of the small intestine
One gram of:
carbohydrate, metabolized in the body, yields more energy when oxidized in a bomb calorimeter
fat, metabolized in the body, yields no per cent more energy than 1g of carbohydrate
protein, metabolized in the body, yields the same energy as when oxidized in a bomb calorimeter
carbohydrate, metabolized in the body, yields about the same energy as 1g of protein
protein per kg body weight is not the adequate daily protein intake for a sedentary adult
Cholesterol:
can be absorbed from the gut by intestinal lymphatics following its incorporation into chylomicrons
can be synthesized in the spleen
in the diet comes mainly from vegetable sources
is eliminated from the body mainly by metabolic degradation
is a precursor of adrenal medulla hormones
Free (non-esterified) fatty acids in plasma:
are provided to fat cells and other tissues by chylomicrons and VLDL
are bound to albumins
decrease when the level of blood adrenaline rises
can be metabolized to release energy in smooth muscle
are not synthesized in the fat depots where they are stored
lmpaired intestinal absorption of:
iron occurs frequently following removal of most of the stomach
iodine leads to a reduction in size of the thyroid gland
water occurs in infants who cannot digest lipids
calcium may occur following removal of the terminal ileum
bile salts may occur following resection of the stomach
Peptic ulcer pain is typically relieved by:
raising the pH of the fluid bathing the ulcer and a drug blocking the gastric proton pump
a drug decreasing the pH
H2 stimulators
a drug which interferes with the action of acetylcholinesterase
a drug which stimulates the gastric proton pump
Fat stores In the adult:
make up less than 5% of average body weight
make up a smaller percentage of body weight in women than in men
release fatty acids when there is increased sympathetic nerve activity
release fatty acids when insulin is injected
enlarge by increasing the number of adipocytes they contain
Metabolic rate can be estimated from measurements of:
total heat loss
the calorific value of the food consumed m the previous 24 hour
oxygen consumption and the respiratory quotient
carbon dioxide production and the respiratory quotient
Complications that may arise after total gastrectomy include
depletion of vitamin B12 stores in the liver
malabsorption of fat due to rapid intestinal transit
impaired defaecation due to loss of the gastrocolic reflex
inability to digest protein
Severe diarrhoea causes a decrease in:
body potassium
antidiuretic hormone level
extracellular fluid volume
total vascular peripheral resistance
Urobilinogen is:
a mixture of colourless compounds also known as stercobilinogen
formed in the reticuloendothelial system from bilirubin
absorbed from the intestine
excreted mainly in the urine
a and c
Surgical removal of 90 % of the small intestine may cause a decrease in:
the fat content of the stools
bone mineralization (osteomalacia)
blood haemoglobin level
body weight
Lack of pancreatic juice in the duodenum may lead to:
the presence of undigested meat fibres in the stools
an increase in the fat content of the films
a decrease in the fat of the faeces
a high prothrombin level in blood
Gastric:
acid secretion in response to a lowered blood gugar is mediated by the hormone gastrin
emptying is facilitated by sympathetic nerve activity
acid secretion increases when histamine H2 , muscarinic M1 or gastrin receptors are activated
acid secretion is inhibited by the presence of food In the duodenum
Constipation is a recognized consequence of:
psychological stress
abnormality of the autonomic nerve supply to the esophagus
a diet that leaves little unabsorbed residue in the gut
over-activity of the thyroid gland as in thyrotoxicosis
Absorption of glucose by intestinal mucosal cells:
relies on a carrier mechanism in the cell membrane
is blocked not by the same agents that block renal reabsorption of glucose
is enhanced by blockade of active sodium transport in the cells
takes place mainly in the ileum
does not involve the same carriers that are used for the absorption of galactose
Muscle tone in the lower oesophagus is:
lower than tone in the middle oesophagus
a major factor in preventing heartburn
increased in pregnancy
decreased by gastrin
increased by anticholinergic drugs
Which of the following are incorrectly paired:
pancreatic alpha amylase-starch
elastase-tissue rich in elastin
renin-coagulated milk
enteropeptidase-trypsinogen
phospholipase A2-phospholipids
All are GIT hormones except:
erythropoietin
somatosmin
Iron Is absorbed in:
jejunum
ileum
colon
in infants, defecation often follows a meal. The cause of colonic contractions in this situation is:
gastro-ileal reflex
increased circulating levels of CCK
gastrocolic reflex
enterogastric reflex
decreased circulating levels of gastrin
Which of the following has the highest pH:
bile in GB
secretions of intestinal glands
Man is unable to digest:
dextrin
glucose
cellulose
maltose
Steatorrhoea may be cooled by all factors except:
pancreatectomy
gastrin secreting tumor
resection of distal ileum
hemolytic jaundice
increascd amount of fat in the stools
Normal swallowing is dependent on the integrity of the:
9 and 10 cranial nerves
pyramidal tract
trigeminal nerve
appetite center of hypothalamus
neurons, secreting VIP
Secretion of the intrinsic factor occurs in
parietal cells of the stomach
chief cells of the stomach
upper abdomen
alpha cells of pancreas
cells of the parotid gland
In which of the following is absorption of water greatest:
mouth
Secretin is released by:
acid in duodenum
acid in stomach
cells in the liver
distention of colon
gallbladder
Vit D is essential for normal:
Fat absorption
Ca absorption
ADH secretion
Protein absorption
Glucose absorption
Gastrin secretion is increased by:
acid in the lumen of stomach
calcitonin
vagal discharge
Saliva is responsible for all except:
deglutition
dental cares prevention
complete digestion of proteins
the concentration of iodine
maintaining the oral pH at about 7.0
Carbonic anhydrase has a role to play in the formation of:
HCL by the parietal cells of the stomach
carbaminhaemoglobin
cerebrospinal fluid in the choroid plexuses
bile salts
