Question | Answer |
Increases the rate of a chemical reaction without becoming part of the product | catalyst |
Provides a standard of comparison for test results | control |
Biologic catalyst; protein in nature | enzyme |
Substance on which a catalyst works | Substrate |
List three characteristics of enzymes. | Specificity (act on one or a small number of substrates); temperature specific; pH specific |
The enzymes of the digetive system are classified as hydrolases. What does this mean? | Hydrolases break down organic food molecules by adding water to the molecular bonds, thus cleaving the bonds between the subunits or monomers. |
Salivary Amylase is produced in the? Site of action? Substrate? Optimal pH? | Salivary glands; oral cavity; starch 6.7-7.0 |
Trypsin is produced where? Site of Action? Substrate? Optimal pH? | Pancreas; small intestine; proteins, 8.0 |
Lipase (pancreatic) is produced where? Site of Action? Substrate? Optimal pH? | Pancreas; small intestine; fats; 7.4-8.0 |
Name the end product of digestion for proteins | amino acids |
Name the end product of digestion for fats | fatty acids and glycerol (monoglycerides) |
Name the end product of digestion for carbohydrates | simple sugars |
The indicator used to test for protein hydrolysis, indicated by a yellow color | BAPNA |
The indicator used to test for the presence of starch, which was indicated by a blue-black color | IKI Lugol's iodine) |
The indicator used to test for the presence of fatty acids, which was evidenced by a color change from blue to pink | litmus paper |
The indicator used to test for the presence of reducing sugars (maltose, sucrose, glucose) as indicated by a blue to green or orange color change | Benedict's solution |
What is the optimal incubatin temperature? | 37 degress C (body temperature) |
Why is bile not considered an enzyme? | Bile only physically seperates the fat droplets. It does not break the molecular bonds as do the digestive enzymes. |
What role does bile play in fat digestion? | Emulsification of fat by bile increases the surface area for lipase activity. |
Why are denatured enzymes nonfunctional? | Their 3-D structures and active sites are necessary for heir activity. If their structures are changed, the active sites change, thus inactivating the enzyme. |
Mechanism of absorption of monosaccharides | Most by active transport in the blood |
Mechanism of absorption of Fatty acids and glycerol | Diffusion, some blood, most lymph |
Mechanism of absorption of amino acids | active transport in blood |
Mechanism of absorption of water | osmosis (diffusion) in blood |
Mechanism of absorption of NA+ CL- CA2+ | Na+, CA2+ are active transport and Cl- is diffusion all in the blood |
A person on a strict diet to lose weight metabolize stored fats at an accelerated rate. How does this affect bloodk pH? | It would become acidic (decrease pH) |
The hormone secretin is produced by what and what are the target organs and effects? | Intestinal mucosa. It stimulates (1) the pancreas to release bicarbonate-rich fluid and (2) the liver to secrete bile. |
The hormone gastrin is produced where and what are it's target organs and effects? | Stomach cells. Gastrin acts on the stomach glands to increase their secretory activity (particularly of HCL) |
The hormone cholecystokinin is produced where and what are its target organs and effects? | Intestinal cells; It stimulates release of enzymes from the pancreas, causes gall bladder contraction and inhibits gastric secretion. |
Swallowing is also refers to as: | deglutition |
Swallowing occurs in two phases | buccal and pharyngeal-esophageal |
Which phase of swallowing is voluntary | buccal |
During the voluntary phase, ______is used to push the food into the back of the throat. | tongue |
During swallowing, the ______ rises to ensure that its passageway is covered by the epiglottis so that the ingested substances don't enter the respiratory passageways | larynx |
It is possible to swallow water while standing on your head because the water is carried along the esophagus involuntarily by the process of | peristalsis |
The pressure exerted by the foodstuffs on teh _________________ sphincter causes it to open, allowing the foodstuffs to enter the stomach | gastroesophageal |
The two major types of propulsive movements that occur in the small intestine are; | peristaltic and segmental |