Biology 20 Unit D part 1

Using this diagram of the digestive system to identify the organ where most of the chemical digestion occurs;

• mouth

• stomach

• small intestine

• large intestine

Using this diagram of the digestive system to identify the organ has a very low pH to activate some enzymes and destroy harmful bacteria.

• mouth

• stomach

• small intestine

• large intestine

The products in this diagram are respresented by the moleculres;

• Y and Z

• W and Z

• X and V

• X and Z

Using this diagram, identify the two molecules not changed in the reaction above;

• Y and Z

• W and Z

• X and V

• X and Z

Using the diagram, if molecule X were removed from the reaction in this diagram, then the reaction would;

• proceed more rapidly

• be inhibited

• proceed at the same rate

• produce more Y and Z

Gastrin is influenced by a positive feedback mechanism. An increase in the amount of protein such as steak during a meal results in;

• increased gastrin secretion resulting in an increase in gastric juice secretion.

• increased gastrin secretion resulting in a decrease in gastric juice secretion.

• decreased gastrin secretion resulting in a decrease in gastric juice secretion.

• decreased gastrin secretion resulting in an increase in gastric juice secretion.

Lacteals (lymph vessels) of the intestinal villi receive;

• amino acids and glucose

• glycerol and glycogen

• peptides and glycerin

• reassembled triglycerides

Digestion is necessary because ingested food molecules

• are too large to be transported across cell membranes.

• must be made water soluble before they can be moved into the blood stream.

• must be combine with vitamins for proper nutrition.

• contain many atoms not required in the body.

On a cold day, the temperature of the air reaching alveoli is raised in the nasal passages because the

• surface area of the turbinates allows for the transfer of heat

• movement of air is increased due to the size of the passageways

• surface area of the turbinates allows for the transfer of moisture

• rate of gas exchange is decreased due to the large number of blood vessels

A mechanical ventilator in a hospital is designed to fulfill several purposes. One is to deliver oxygen-carbon dioxide balanced air to the patient at a prescribed rate. Why would carbon dioxide be included in the air?

• carbon dioxide is necessary to reduce the hemoglobin

• pure oxygen causes the formation of nitrogen bubbles in the blood

• carbon dioxide stimulates the respiratory centre in the brain

• pure oxygen cannot be absorbed by the lungs unless diluted