Digestion and Excretion Flashcards
What happens to the bile salts once they’ve emulsified the fats?
- They are excreted in faeces
- They are broken down in the Ileum
- They are reabsorbed in the Ileum then broken down by the liver
- They are reabsorbed and reused by the liver for bile
- They react with the fat and remain in contact with it until it is deposited in adipose tissues
4.They are reabsorbed and reused by the liver for bile
What enzyme normally breaks down triglyceride in the blood? A.Beta oxidase B.HMG-CoA reductase C.Lipoprotein lipase D.Pancreatic lipase E.Phospholipase A2
C.Lipoprotein lipase
The action of histamine exemplifies what kind of signalling? A.Autocrine B.Endocrine C.Exocrine D.Neuroendocrine E.Paracrine
E.Paracrine
A man is stabbed and develops paleness, fatigue and loss of weight. What is the most likely cause of his symptoms?
- Septicaemia
- Vitamin B12 malabsorption
- Haemorrhagic anaemia
- Infected wound
- Aplastic anaemia
2.Vitamin B12 malabsorption
Angiotensin 11 is synthesised and released from which structure? A.Adrenal cortex B.Anterior pituitary C.Hypothalamus D.Kidney E.Posterior pituitary
A.Adrenal cortex
Which of the following cells within gastric pits release intrinsic factor? A) Chief cells B) Parietal cells C) D cells D) G cells
B) Parietal cells
Which of the following cells are not found in gastric pits located in the fundus of the stomach? (more than one) A) Chief cells B) Parietal cells C) D cells D) G cells
C) D cells
D) G cells
Which of the following statements relating to gastric acid release is/are true? (more than one)
A) Gastric acid is released in response primarily to proteins arriving within the stomach
B) Gastrin is an important paracrine mediator of gastric acid release
C) The parasympathetic nervous system can increase gastric acid release indirectly via gastrin
D) H2 receptor agonists are used as antacids in the treatment of stomach ulcers
A) Gastric acid is released in response primarily to proteins arriving within the stomach
C) The parasympathetic nervous system can increase gastric acid release indirectly via gastrin
Which of the following statements relating to gastric emptying is correct?
A) Gastric emptying is controlled only by the autonomic nervous system
B) An increase in osmolarity within the duodenum speeds up gastric emptying
C) Gastric emptying is controlled mainly by the release of gastrin and somatostatin from the stomach mucosa
D) Gastric emptying is influenced primarily by regulators released from the duodenum, which are mainly inhibitory
D) Gastric emptying is influenced primarily by regulators released from the duodenum, which are mainly inhibitory
Which of the following statements relating to absorption is correct?
A) Most nutrients are absorbed across the membranes of GI epithelial cells by passive transport
B) Chemical digestion by secreted enzymes within the GI lumen is sufficient to produce molecules that are small enough to be absorbed
C) Lipids are absorbed from the GI lumen into GI epithelial cells in the form of chylomicrons
D) Amino acids rely on active secondary transport to cross the intestinal epithelium
C) Lipids are absorbed from the GI lumen into GI epithelial cells in the form of chylomicrons
Which of the following statements is correct?
A) The gall bladder synthesises and stores bile between meals
B) The hormones secretin and CCK promote pancreatic secretions
C) Bile salts are recycled via the enterohepatic circulation
D) Pancreatic and biliary secretions are stimulated by an increase in pH within the duodenum
B) The hormones secretin and CCK promote pancreatic secretions
C) Bile salts are recycled via the enterohepatic circulation
Which of the following describes the effects of statins on cholesterol metabolism?
A) Statins inhibit the synthesis of cholesterol within the liver
B) Statins inhibit the absorption of cholesterol from the GI tract
C) Statins upregulate LDL receptors in liver cells
D) Statins increase LDL levels
A) Statins inhibit the synthesis of cholesterol within the liver
C) Statins upregulate LDL receptors in liver cells
What secretes the enzyme that normally breaks down fat in the intestine?
A. Gall bladder B. Liver C. Pancreas D. Small intestine E. Stomach
Answer: C
Learning point: Endo/Exocrine secretions in the GI tract
- A baby is identified as having a genetic disorder which interferes with normal cholesterol production.
What biological molecules are dependent on this compound for synthesis?
A. Nucleic acids B. Polypeptides C. Polysaccharides D. Steroids E. Triglycerides
Answer: D
Learning point: Steroid synthesis
- The kidney secretes a protein that triggers a cascade which regulates blood sodium concentration and blood pressure.
What is the name of this protein?
A. Angiotensin II B. Angiotensinogen C. Erythropoietin D. Renin E. Vasopressin
Answer: D
Learning point: function of the kidney
- A fit and healthy 21 year old male Medical Science student with normal kidneys decreases his intake of dietary sodium by half over a period of two months.
Which of the following would be expected to be increased in response to this restriction of dietary sodium?
A. Arterial pressure B. Extracellular fluid volume C. Release of Atrial Natriuretic Peptide (ANP) D. Release of renin E. Sodium excretion
Answer: D
Learning Point: Fluid Homeostasis
- A 25 year old man suffers from a stab wound in the abdomen, requiring a removal of 150 cm of terminal ileum. Two years after the surgery, he complains of increasing malaise and watery diarrhoea. He reports eating a normal and unrestricted diet. A diagnosis of anaemia is made.
What is the most likely cause of his anaemia?
A. Folate malabsorption B. Impaired secretion of intrinsic factor (IF) C. Iron deficiency D. Malabsorption of IF-B12 complex E. Pancreatic insufficiency
Answer: D
Learning Point: Absorption in the GI tract
What is the order of the layers of the stomach?
A) Serosa, adventitia, muscularis propria, submucosa, mucosa
B) Serosa, muscularis propria, mucosa, submucosa
C) Mucosa, Muscularis propria, Serosa, Adventitia
D) Serosa, muscularis propria, adventitia, submucosa, mucosa
A) Serosa, adventitia, muscularis propria, submucosa, mucosa
Which cell secretes HCL and IF
Parietal
Which cells secretes pepsinogen and gastric lipase
chief
G cells secrete what?
gastrin
Which cells secrete somatostatin?
D cell
ECL cells secrete what?
Histamine
What is the order of the small intestine? A) Duodenum, Ileum, Jejunum B) Duodenum, Jejunum, Ileum C) Jejunum, Ileum, Duodenum D) Ileum, Jejunum, Duodenum
A) Duodenum, Ileum, Jejunum
Which nerve innervates the stomach? A) Iliac B) Gastric C) Sciatic D) Vagus
D) Vagus
Fill in the blank: the duodenum has broad villi which contain -------- glands, to produce an alkaline substance to neutralise chyme. A) Bartolin B) Seminiferous C) Brunners D) Acinar
C) Brunners