Role of HCl

Q.

What is the role of HCl acid in our stomach?

Q.

What would happen if $HCl$ were not secreted in the stomach?

Q.

What is the role of hydrochloric acid in protein digestion?

Q.

What is the role of HCl in human digestive system?

Q.

Describe the process of digestion of protein in stomach.

Q. If for some reason the parietal cells of the gut epithelium become partially nonfunctional, what is likely to happen?

1. Pancreatic enzymes, especially trypsin and lipase will not work efficiently
2. Proteins will not be adequately hydrolysed by pepsin to proteoses and peptones
3. pH of stomach will fall abruptly
4. Steapsin will not be effective

Q. What is the use of HCl secreted by the stomach?

1. Converts pepsin to pepsinogen
2. Does not help in the digestion of protein
3. Converts pepsinogen to pepsin
4. Helps in the survival of bacteria

Q.

Semi-digested food in the stomach is converted into chyme by the action of gastric juice

1. True
2. False

Q. Which of the following cells produce HCl?

1. Mucous neck cells
2. Peptic cells
3. Oxyntic cells
4. Chief cells

Q. If HCl is not secreted by the parietal cells, then the possible effect will be ____________.

1. All of the above
2. presence of acidic condition
3. no activation of pepsinogen
4. no activation of trypsionogen

Q. What is the use of HCl secreted by the stomach?

1. Converts pepsin to pepsinogen
2. Does not help in the digestion of protein
3. Helps in the survival of bacteria
4. Converts pepsinogen to pepsin

Q. Read the following statements (A-D).
(A) The stomach stores the food for $4-5$ hours.
(B) The food mixes throughly with the acidic intestinal juice.
(C) Trypsinogen is activated by an enzyme enterogastrone, secreted by the intestinal muscosa.
(D) Renin is enzyme found in gastric juice of infants which helps in digestion of milk protein.
How many of the given statements are wrong?

1. Four
2. One
3. Two
4. Three

Q.

Does the pancreas secrete bicarbonate?

Q. Protection of the walls of the stomach against the action of its own digestive juices:

1. Results from the presence of an anti–enzyme chemical formed by the gastric glands
2. Results from the nervous reactions of the lining of the stomach
3. Is controlled by a centre in the medulla of the brain
4. Results from the neutralizing, buffering, and a coating mucus covering its inner surface

Q. Assertion- pH of the stomach is more than 7.
Reason- Stomach contains oxyntic cells that produce HCl.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion
3. The assertion is false but the reason is true
4. Both assertion and reason are false

Q. Digestion of which component of food will be affected if the pH of stomach is made 7?

1. Protein
2. Sucrose
3. Vitamins
4. Fat

Q. List three important properties of enzymes.

Q. If gall bladder of a man is removed

1. Effect of pancreatic juice upon food is impaired
2. Acidity continues in duodenum
3. Fat digestion is not possible
4. All of the above.

Q. What will happen if the secretion of parietal cells of the gastric glands is blocked with an inhibitor?

1. Gastric juice will be deficient in chymosin
2. Gastric juice will be deficient in pepsinogen
3. Enterokinase will not be released from the doudenal mucosa and so, trypsinogen is not converted to trypsin
4. In the absence of HCl secretion, inactive pepsinogen is not converted into the active enzyme pepsin

Q. Assertion :Hydrochloric acid does not digest the stomach wall. Reason: Hydrochloric acid is unable to denature the proteins.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. Assertion :Mucosal epithelium of gut has goblet cells, which secrete mucus. Reason: The mucus in the gastric and pancreatic juice protects the mucosa from excoriation by acidic secretion.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. If PH of stomach is made 7, which component of the food would be affected?

1. Starch
2. Proteins
3. Fat
4. Sucrose

Q. Mucus helps frog in forming

1. Thick skin
2. Dry skin
3. Smooth skin
4. Moist skin

Q. Main function of HCl in stomach is to

1. Activates amylase enzyme
2. Facilitate absorption of food
3. Dissolve enzymes
4. Activate pepsinogen to pepsin

Q. Identify the missing options regarding the physiology of digestion in the stomach:
$$\begin{array}{ccc}\text{Secretion}& \text{Action}& \text{Product}\\ \text{Salivary amylase}& \text{i)}& \text{Decrease of pH by HCl}\\ \text{HCl}& \text{ii)}& \text{Chyme}\\ \text{Pepsinogen, Prorennin}& \text{iii)}& \text{Pepsin, rennin}\\ \text{Proteins}& \text{iv)}& \text{Proteoses and Peptones}\end{array}$$

1. i) Acidification ii). Activation by HCl iii). Digestion iv).Deactivation

2. i) Deactivation ii). Acidification iii). Activation by HCl iv).Digestion

3. i)Activation by HCl ii)Digestion iii)Deactivationiv)Acidification

4. i). Digestionii).Deactivationiii). Acidification iv)Activation by HCl

Q. Identify the missing options regarding the physiology of digestion in the stomach:
$$\begin{array}{ccc}\text{Secretion}& \text{Action}& \text{Product}\\ \text{Salivary amylase}& \text{i)}& \text{Decrease of pH by HCl}\\ \text{HCl}& \text{ii)}& \text{Chyme}\\ \text{Pepsinogen, Prorennin}& \text{iii)}& \text{Pepsin, rennin}\\ \text{Proteins}& \text{iv)}& \text{Proteoses and Peptones}\end{array}$$

1. i) Acidification ii) Activation by HCl iii) Digestion iv) Deactivation
2. i) Deactivation ii) Acidification iii) Activation by HCl iv) Digestion
3. i) Activation by HCl ii) Digestion iii) Deactivation iv) Acidification
4. i) Digestion ii) Deactivation iii) Acidification iv) Activation by HCl

Q. Which of the following exhibits keto-enol tautomerism at body pH?

1. None of the above
2. Alanine
3. Aspartic acid
4. Thymine

Q. ......... Esters of glycerol and fatty acids.

Q. Choose the correct answers from the alternatives given.
Which of the following enzymes has the lowest pH optimum?

1. Pepsin
2. Trypsin
3. Salivary amylase
4. Pancreatic amylase

Q.

Identify the steps (denoted by numerals) in physiology of digestion in stomach.

i).Food $\stackrel{HCl}{\underset{KillsBacteria}{⟶}}$ Chyme

ii).Pepsinogen Prorennin $\stackrel{HCl}{\underset{Activation}{⟶}}$ Pepsin Rennin

iii).Proteins $\stackrel{Pepsin}{⟶}$ Proteases Peptones

iv).Milk Casein $\stackrel{Rennin}{⟶}$Para casein $\stackrel{Calcium}{⟶}$ Calcium paracaseinate

1. i). Acidification ii). Activation by HCl iii). Digestion iv). Digestion of Milk in infants
2. i). Deactivation ii). Acidification iii). Activation by HCl iv). Digestion
3. i). Activation by HCl ii). Digestion iii). Deactivation iv). Acidification
4. i). Digestion ii). Deactivation iii). Acidification iv). Activation by HCl