Tag: parts of the digestive system

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Questions Related to parts of the digestive system

Multiple choice parts of the digestive system digestive system of human human digestive system digestion and absorption biology nutrition deficiency diseases digestive system

In which of the following structures protein digestion first occurs?

  1. Mouth

  2. Stomach

  3. Large intestine

  4. Small intestine
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

  • Digestion involves the mixing of food, its movement through the digestive tract, and the chemical breakdown of the large molecules of food into smaller molecules.
  •  Digestion begins in the mouth when we chew and swallow, and then it is passed on to the stomach where digestion takes place by gastric juices and enzymes secreted by the stomach and then it is passed to the small intestine where the digestion is completed. 
  • Pepsin is an enzyme which is released by zymogenic cells, the chief cells in the stomach and that degrades food proteins into peptides. Hence, the stomach is the structure where the protein digestion first occurs.
So, the correct answer is 'Stomach'.

Multiple choice parts of the digestive system digestive system of human human digestive system digestion and absorption biology nutrition deficiency diseases digestive system

A digestive juice with a pH of approximately 2 is found inside the

  1. mouth

  2. stomach

  3. pancreatic duct

  4. small intestine
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • The pH of your stomach varies, from 1-2 up to 4-5. When you eat, the stomach releases enzymes called proteases as well as hydrochloric acid to help in digestion.
  • By itself, the acid doesn't really do much for digestion, but the proteases that cleave proteins work best in an acidic environment or low pH, so after a high-protein meal, your stomach pH may drop to as low as 1 or 2. 
  • However, buffers quickly raise the pH back to 3 or 4. After the meal has been digested, your stomach pH returns to a resting level of about 4 or 5. Hence, inside of the stomach, a digestive juice with a pH of approximately 2 is found.
So, the correct answer is 'stomach'.
Multiple choice parts of the digestive system digestive system of human human digestive system digestion and absorption biology nutrition deficiency diseases digestive system

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
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • In humans and other mammals pepsin produced in the stomach by chief cells in an inactive form called pepsinogen. 
  •  Once the pepsinogen is released into the stomach, the low pH from the gastric acid helps in the conversion of pepsinogen into pepsin, the active enzyme.
  •  Many proteins are denatured at low pH, and most enzymes whether or not they denature require a higher pH for activity. Hence, pepsin is the enzymes has the lowest pH optimum.
So, the correct answer is 'pepsin'.
Multiple choice parts of the digestive system digestive system of human human digestive system digestion and absorption biology nutrition deficiency diseases digestive system

Pepsin is an enzyme which acts in

  1. acidic medium in the stomach

  2. alkaline medium in the stomach

  3. alkaline medium in the duodenum

  4. acidic medium in the duodenum
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

  • Pepsin is an enzyme which is released by zymogenic cells, the chief cells in the stomach and that degrades food proteins into peptides.
  •  It is most active in acidic environments.
  •  It exhibits maximal activity at pH 2.0 and is inactive at pH 6.5. Hence, Pepsin is an enzyme which acts in an acidic medium in the stomach.
So, the correct answer is 'acidic medium in the stomach'.

Multiple choice parts of the digestive system digestive system of human human digestive system digestion and absorption biology nutrition deficiency diseases digestive system

Which of the following molecules is incorrectly paired with its source?

  1. Lysozyme-gastric juices

  2. Histamine-injured cells

  3. lnterferons-virus infected cells

  4. Immunoglobulins-plasma cells
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Histamine is an organic nitrogenous compound involved in local immune responses, as well as regulating physiological function in the gut and acting as a neurotransmitter for the brain, spinal cord, and uterus. Histamine is involved in the inflammatory response and has a central role as a mediator of itching. 

Interferons (IFNs) are a group of signaling proteins made and released by host cells in response to the presence of several viruses. In a typical scenario, a virus-infected cell will release interferons causing nearby cells to heighten their anti-viral defenses.
Immunoglobulins, also known as antibodies, are glycoprotein molecules produced by plasma cells (white blood cells). 
Lysozyme is a special enzyme found in tears, saliva, sweat, and other body fluids. Other mucosal linings, such as the nasal cavity, also contain lysozyme. It destroys bacteria that attempt to enter our body through these passageways. In the case of tears, they protect our eyes from bacterial invaders.

So, the correct option is 'Option A'.

Multiple choice parts of the digestive system digestive system of human human digestive system digestion and absorption biology nutrition deficiency diseases digestive system

Partially digested semisolid food formed in stomach is ...........

  1. Chyle

  2. Chyme

  3. Bolus

  4. Chylomicron
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Chyme is the name given to the partially digested food, formed in the stomach and enters into the small intestine(duodenum) via the pyloric valve. Chyme, also known as chymus has the consistency of oatmeal(semisolid). Chyme is a thick semisolid mass of partially digested food and digestive secretions during the digestion process. Hence, partially digested semisolid food in the stomach is chyme.

So, the correct answer is 'Chyme'.

Multiple choice parts of the digestive system digestive system of human human digestive system digestion and absorption biology nutrition deficiency diseases digestive system

Pepsin digests .............. .

  1. Proteins in stomach

  2. Carbohydrates in duodenum

  3. Proteins in duodenum

  4. Carbohydrates in stomach
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Pepsin is produced in the stomach and is one of the main digestive enzymes in the digestive systems of humans and many other animals, where it helps digest the proteins in food. Zymogenic cell or peptic cell is a cell in the stomach that releases pepsinogen and chymosin.

The proenzyme pepsinogen(inactive), on exposure to hydrochloric acid, gets converted to the active enzyme pepsin. Pepsin hydrolyses proteins to polypeptide chains and initiates protein digestion in the digestion process in humans. Hence, the pepsin digests protein in the stomach.

So, the correct option is 'proteins in the stomach'.