The small intestine of a person contains a lower concentration of glucose than is present in the blood. The cells of the villi absorb glucose. By which process is the glucose absorbed?
- A. by active transport against the concentration gradient
- B. by active transport down the concentration gradient
- C. by diffusion against the concentration gradient
- D. by diffusion down the concentration gradient
Correct Answer: A
Rationale: Glucose absorption in the small intestine occurs through active transport, particularly when the concentration of glucose is higher in the blood than in the intestine. This requires energy to move glucose against its concentration gradient.
You may also like to solve these questions
Match: Monosaccharide
- A. simplest component of a carbohydrate
- B. building block of proteins
- C. component of nucleic acids
- D. form of stored energy
Correct Answer: A
Rationale: Monosaccharides, such as glucose, are the simplest units of carbohydrates and serve as immediate energy sources.
Submandibular gland following is true except:
- A. Has thick capsule & thin septa
- B. Formed mainly of serous acini
- C. Has no striated ducts
- D. Secrete 70% of salivary secretion
Correct Answer: C
Rationale: The submandibular gland has prominent striated ducts, like other major salivary glands.
What are the substrate and end-products of digestion by the enzyme lipase?
- A. substrate: triglycerides, end-products: fatty acids and glycerol
- B. substrate: proteins, end-products: amino acids
- C. substrate: carbohydrates, end-products: monosaccharides
- D. substrate: nucleic acids, end-products: nucleotides
Correct Answer: A
Rationale: Lipase acts on triglycerides, breaking them down into fatty acids and glycerol.
A client is to have a sigmoidoscopy to examine the sigmoid area of the gastrointestinal system. In teaching the client about the procedure, the nurse would explain that the purpose of the procedure is to examine the:
- A. Distal large intestine
- B. Stomach and small intestine
- C. Liver
- D. Pancreas
Correct Answer: A
Rationale: A sigmoidoscopy examines the sigmoid colon, part of the distal large intestine.
Why is pepsin not secreted into the stomach?
- A. Because it would digest the stomach
- B. It is secreted into the stomach
- C. Because it would be inactivated by the acid in the stomach
- D. It is secreted into the intestine
Correct Answer: B
Rationale: Pepsin is secreted into the stomach as pepsinogen by chief cells and activated by stomach acid. It does not digest the stomach due to the protective mucus layer.