Digestion and Absorption MCQs

Which of the following statements about chyme formation and gastric storage are correct?

I. The stomach stores food for about 4 to 5 hours.
II. Churning movements of the muscular stomach wall thoroughly mix food with acidic gastric juice.
III. The thoroughly mixed, acidic food in the stomach is called chyme.
IV. Chyme is highly alkaline due to the protective bicarbonates of the gastric mucosa.

Assess the correctness of the following statements regarding infant digestion and gastric enzymes:

I. Rennin is a proteolytic enzyme found in the gastric juice of infants.
II. Rennin helps in the digestion of milk proteins in infants.
III. Gastric glands secrete small amounts of lipases in addition to proteases.
IV. Rennin continues to be secreted in high amounts throughout adult life.

Read the statements regarding the activation of pancreatic enzymes in the small intestine:

I. Trypsinogen is activated into active trypsin by the enzyme enterokinase.
II. Enterokinase is secreted directly by the exocrine pancreas.
III. Active trypsin activates other inactive pancreatic enzymes like chymotrypsinogen and procarboxypeptidases.
IV. Enterokinase is a component of the bile duct secretion.

Match the digestive sphincters with their locations and functions:

I. The gastro-oesophageal sphincter regulates the opening of the oesophagus into the stomach.
II. The pyloric sphincter guards the opening of the stomach into the duodenum.
III. The sphincter of Oddi guards the opening of the common hepato-pancreatic duct into the duodenum.
IV. The ileo-caecal valve regulates the backflow of faeces from the caecum into the ileum.

Evaluate the statements regarding the human liver anatomy:

I. The liver has two lobes and is situated in the abdominal cavity just below the diaphragm.
II. Hepatic lobules are the structural and functional units of the liver.
III. Each hepatic lobule is covered by a thin connective tissue sheath called Glisson's capsule.
IV. Hepatic cells are arranged inside the lobules in the form of cords.

Regarding absorption in the human oral cavity, which of the following statements is/are correct?

I. Certain drugs can be absorbed directly through the oral mucosa.
II. Drugs must come in contact with the mucosa of the mouth and the lower side of the tongue.
III. Absorbed drugs enter directly into the blood capillaries lining the oral cavity.
IV. Significant absorption of simple sugars also takes place in the mouth.

Read the following statements about the final pathways of digested waste and nutrient utilization:

I. The absorbed substances finally reach the tissues which utilize them for their activities, a process called assimilation.
II. The egestion of faeces to the outside through the anal opening is called defaecation.
III. Defaecation is an involuntary reflex process that cannot be consciously controlled.
IV. Mass peristaltic movements are responsible for carrying out defaecation.

Analyze the statements regarding the human pancreas and select the correct option:

I. The pancreas is an elongated compound gland containing both exocrine and endocrine portions.
II. It is situated between the limbs of the 'U' shaped duodenum.
III. The exocrine portion secretes an alkaline pancreatic juice containing digestive enzymes.
IV. The endocrine portion secretes the hormones insulin and glucagon.

Read the statements about succus entericus and identify the correct combination:

I. Succus entericus is formed by the secretions of the brush border cells along with goblet cells.
II. It contains enzymes such as dipeptidases, maltase, lactase, sucrase, nucleosidases, and lipases.
III. It contains nucleases that break down nucleic acids into nucleotides.
IV. Succus entericus functions at an optimal alkaline pH of 7.8.

Evaluate the statements from the Unit 5 introduction regarding the study of life forms:

I. The reductionist approach in biology heavily relied on cell-free systems and surviving tissue models.
II. Molecular physiology became almost synonymous with biochemistry and biophysics.
III. Systems biology states that all living phenomena are emergent properties due to interactions among components.
IV. Regulatory networks of molecules, cells, and tissues each create emergent properties.