Chap 44-45: Fluid, electrolyte, nutrient + lab evals (with ratio) Flashcards
Step 3 in Cobalamin absorption
Cobalamin binds to haptocorrin
Form of folate that must be deconjugated before being absorbed
Dietary folate
Also known as R type binder
Haptocorrin
T/F: Secretion of K in the large intestine is an active process
False
Patient with Cystic fibrosis have defect in apical chloride channel in epithelial cells. Such patients have major defect in?
a. Small intestinal NaCl and Water secretion
b. Small intestinal NaCl and Water absorption
Small intestinal NaCl and Water secretion
Loss of gastric fluid by vomiting leads to metabolic alkalosis, Diarrhea leads to _____ because bicarbonate is _____ in _____
Metabolic acidosis; Secreted; Both small and large intestine
Not true regarding epithelial sodium channel
Transporters are Cl-HCO3 exchangers
Most important mechanism of Sodium absorption after meals
Sodium glucose cotransport (SGLT)
Movement of K in the small intestine is mainly by
Solvent drag
Net absorption of fluid and electrolyte during interdigestive state is primarily due to
Parallel Na-H and Cl-HCO3 exchangers
Colon is solely responsible for the net secretion of: a. K b. Na c. Cl d. HCO3
K+
Transport of solute across the apical membrane may
be coupled to fluid movement by
Solvent drag
Which of the following increase fluid secretion
Histamine
Which of the following increases sodium absorption in
proximal intestine
Alkalinity of the luminal fluid
HCO3 stimulated sodium absorption occurs in
Proximal part of Small intestine
Structure NOT found in colon
Villi
Largest contribution to the intestinal fluid volume
Gastric secretion
Note: Gastric 2L/day
Pancreatic and Salivary 1.5L/day
Small Intestine 1L/day
Bile 0.5L/day
Fluid and electrolyte transport is increased in jejunum
compared to ilium because of the following reason
a. Lower transepithelial voltage
b. Tight junctions are more leaky
c. Higher passive movement of NaCl
d. AOTA
All of the above
Lower transepithelial voltage
Tight junctions are more leaky
Higher passive movement of NaCl
Mechanism of micellar transport to enterocyte
a. Collision
b. Nonionic diffusion
c. Carrier mediated transport
d. AOTA
AOTA
a. Collision
b. Nonionic diffusion
c. Carrier mediated transport
Pancreatic peptidase in which the activating agent is
enteropeptidase
a. Chymotrypsinogen
b. Proelastase
c. Procarboxypeptidase
d. Trypsinogen
Trypsinogen
Compose 30 to 40% of dietary carbohydrates
Sucrose and Lactose
45-60% starch (polysaccharide)
30-40% sucrose and lactose (disaccharides)
5-10% fructose and glucose (monosaccharides)
DMT1 absorbs what form of iron
Nonheme iron
Note: Heme iron enters by binding to brush-border proteins or through endocytic mechanism
Re-esterification of digested lipids, Step 4
Nascent chylomicrons and VLDL arrive at the cis face of Golgi
True about feces
Hypertonic (due to bicarbonate and potassium ions)
T/F: Excess vitamins and minerals compromises the Immune system
True
Ratio:
Vitamin E, an antioxidant, reduces production of superoxide radicals. These radicals are used by WBCs to kill bacteria.
Which is true about Cystinuria and Hartnup disease?
a. Hartnup disease - defect inabsorption of Cationic Amino acids
b. Cystinuria - defect in absorption of Neutral Amino acids
c. Both diseases are autosomal DOMINANT
d. Both diseases, absorption of oligopeptides with neutral or cationic amino acids are normal
d. Both diseases, absorption of oligopeptides with neutral or cationic amino acids are normal
Which of the following of ENaC?
a. Regulated by aldosterone
b. Inhibited by micromolar amiloride concentration
c. AOTA
AOTA
Mediates efflux of monosaccharides across basolateral membrane in epithelial cells?
GLUT2
Most important function of Vitamin D in the active uptake of Ca2+
a. Uptake of Ca2+ across apical membrane via TRP6 Ca2+ channel
b. Extrusion of Ca2+ at the basal membrane via Ca pump and Na-Ca exchanger
c. Ca2+ binds to a protein, Calbidin
c. Ca2+ binds to a protein, Calbidin
Fluid absorption in small intestine
6.5L/day
Notes:
Fluid LOAD in the SI is 8.5L/day
SI MAXIMUM fluid absorptive capacity is 15-20L/day
Colon LOAD or ileocecal flow is 2.0 L/day
Colon fluid ABSORPTION is 1.9 L/day
Colon MAXIMUM absorptive capacity is 4-5 L/day
Ratio of saturated to unsaturated
Increase in animal fat, Decrease in plant fat
Mechanism of Sodium absorption
a. Hyperfunctioning DRA
b. Luminal alkalinity
c. AOTA
Aota
True of emulsification of dietary fat, EXCEPT
a. Decrease area oil-water interface
b. Increase ratio of surface area to volume
c. Reduce size of lipid droplet
DECREASE area for oil-water interface
The following are found in the core of lipid droplet, EXCEPT
a. Lysolecithin
b. TAG
c. DAG
d. Cholesteryl esters
Lysolecithin
Which of the following statements is false?
a. Amylopectin contains more branches than glycogen, and is considered as Animal starch
b. Amylose is a straight chain containing a1-4
c. Amylopectin contains a1-4 and a1-6 chains
Amylopectin contains more branches than glycogen, and is considered as Animal starch
Ratio: Glycogen has more branches and is the animal starch
All of the following are mainly absorbed in the duodenum, EXCEPT
a. Folate
b. Calcium
c. Iron
d. Cobalamin
Cobalamin
Ratio: Cobalin bound to Intrinsic Factor is absorbed in the distal ileum
Active Calcium absorption occurs at?
a. Duodenum
b. Jejunum
c. Ileum
d. Colon
Duodenum
Which mechanism for sodium absorption is used by enterocytes?
A. Na-H exchanger
B. Na-Glucose cotransport
C. Na-Cl cotransport
D. AOTA
Aota
Substrate for amylase
a. Maltose
b. Starch
c. Carbohydrate
d. Maltose and Starch
e. Starch and Carbohydrates
Starch and Carbohydrates
Which of the following is true of enzymes?
a. Become part of the product
b. Used up in the reaction
c. Slow down the rate of reaction
d. Their activity can be affected by temperature and pH
Their activity can be affected by temperature and pH
The IKI reagent tests for the presence of?
a. Starch
b. Maltose
c. Glucose
d. Protein
Starch
Which of the following is/are end product(s) of starch digestion?
a. Amylase
b. Maltose
c. Glucose
d. Amylose and maltose
e. Maltose and glucose
Maltose and glucose
Hydrolases are enzymes that break down large molecules into smaller subunits through the addition of:
a. Acid
b. Water
c. Salt
d. Base
Hydro = Water
Which of the following is true of enzymes and substrates?
a. The substrate forms a covalent bond at the active site of the enzyme.
b. The enzyme is acted upon by the substrate.
c. Enzymes are specific about the substrates they act upon.
d. If the product of catalysis is present, the enzyme is not acting on the substrate.
Enzymes are specific about the substrates they act upon.
Which of the following is/are reducing sugar(s)?
a. Starch
b. Cellulose
c. Maltose
d. Glucose
e. Both glucose and maltose
Both glucose and maltose
Cellulose and starch are both
a. Found in the cell walls of plants
b. Polymers of glucose
c. Polysaccharides
d. Polymers of glucose and found in the cell walls of plants
e. Polymers of glucose and polysaccharides
Polymers of glucose and polysaccharides
Note: Only cellulose is found in plant cell wall
Proteins and peptides are formed by joining amino acids with a special type of covalent bond called a peptide bond. Which of the following enzymes do you think would be specific for a peptide bond?
a. Amylase
b. Cellulose
c. Peptidase
d. Lipase
Peptidase
The Benedict’s assay tests for the presence of
a. Starch
b. Cellulose
c. Reducing sugar
d. Peptides
Reducing sugar
Where in the body does protein digestion begin?
a. Mouth
b. Stomach
c. Small intestine
d. Esophagus
stomach
The substrate/s for pepsin is/are
a. Protein
b. Peptide
c. Starch
d. Protein and peptides
e. Protein, peptides and starch
protein and peptides
Pepsin would be most active in
a. Mouth
b. Stomach
c. Small intestine
d. Mouth and stomach
Stomach
Ratio: Activation of pepsinogen to pepsin and optimal pepsin activity occur in the low pH environement of the stomach
If pepsin is digesting an actual protein substrate, the product would be:
a. Peptides
b. Amino acids
c. Peptides and amino acids
d. BAPNA
Peptides and amino acids
With more enzyme activity, the optical density
a. Increased
b. Decreased
c. Stayed the same
Increased
Which of the following is/are true of bile?
a. It works by a chemical process.
b. It works by a physical process.
c. It is an enzyme.
d. It works by a chemical and physical process.
It works by a physical process.
When fatty acids are liberated by lipase, the pH
a. Increases
b. Decreases
c. Stays the sam
decreases
Ratio: Release of fatty ACID causes low pH
One of the products of the chemical digestion of lipids is
a. Bile salts
b. Lipase
c. Monosaccharides
d. Fatty acids
Fatty Acids
Note: The others are DAG, MAG or glycerol
Spectrophotometer measures
a. Starch
b. Glucose
c. Enzyme activity
d. Optical density
Optical Density
Substrate of amylase
a. Starch
b. Glucose
c. Maltose
d. Starch and Maltose
Starch and Maltose
