Digestive/Circulatory System IB Bio HL

A fluid sample is taken from the digestive tract of a mammal. The sample is basic (alkaline) and able to digest starch proteins. From which part of the digestive tract was the fluid taken?

• Mouth

• Stomach

• Small Intestine

• Gall Bladder

Where is the absorption of digested food carried out?

I. Villi

II. Pancreas

III. Small intestine

• I. only

• I and II only

• I and III only

• I, II, and III

Where does the digestion of polypeptides start in humans?

• Mouth

• Esophagus

• Stomach

• Small Intestine

Which organ in the human body secrete lipase, amylase, and protease

• Pancreas

• Liver

• Gall Bladder

• Small Intestine

Glucose is absorbed through protein channels in the plasma membrane of epithelium cells in the small intestine. Which characteristics of glucose prevent its diffusion through the phospholipid bilayer?

• It is non-polar and therefore hydrophobic

• Its hydrogen bonds link with amino acids in the protein channel

• It is polar and therefore hydrophilic

• Its covalent bonds interact with the phospholipids

In which process is "surface area" of key importance for humans?

• Reabsorption of glucose in the proximal convoluted tubule

• Release of surfactants by type I pneumocytes

• Display of antibodies by red blood cells

• Secretion of enzymes by villi of the small intestine

What are features of the enzyme amylase?

• Substrate: starch, Source: salivary glands, pH: 7

• Substrate: lignin, Source: pancreas, pH: 1.5

• Substrate: cellulose, Source: liver, pH: 4

• Substrate: glycogen, Source: kidney, pH: 9

Celiac disease causes the destruction of the villi cells. Which of the following is most likely to happen to people with celiac disease?

• Incomplete digestion of fats

• Poor absorption of calcium

• Increased levels of glucose in blood

• Damage in the esophagus caused by increase in acid content of the stomach

Which structure produces lipase?

• Liver

• Pancreas

• Gall Bladder

• Small Intestine

The digestive system hydrolyses macromolecules into monomers for absorption. Which chemical(s) produced by humans can perform hydrolysis

I. Cellulase

II. Glycogen

III. Amylase

• I and III only

• II and III only

• III only

• I, II, and III