a
Give a reason for the following
Protein digestion begins in the stomach.
b Vill has a rich supply of blood capillaries and lacteals.
C. Bile has sodium bicarbonate.
d.
Excess amino acids are never stored in our bodies.
e. Pepsin and trypsin are secreted in inactive forms.
Answers
Answer:
answer of question a)
Explanation:
Enzymatic digestion of proteins begins in the stomach with the action of the enzyme pepsin. Proteins are large globular molecules, and their chemical breakdown requires time and mixing. Protein digestion in the stomach takes a longer time than carbohydrate digestion, but a shorter time than fat digestion.
Answer:
carbohydrates are mainly taken in the form of amylose and glycogen. amylases hydrolyze the long carbohydrate chains that break amylose down into disaccharides, and glycogen into polysaccharides. the enzymes in the small intestine then break these down to monosaccharides.
proteins are digested by hydrolysis of the carbon–nitrogen (c–n) bond. peptidases are secreted in an inactive form, to prevent auto-digestion. endopeptidases cleave the polypeptides at the interior peptide bonds, and the exopeptidases cleave the terminal amino acids.
fats are digested by lipases that hydrolyze the glycerol fatty acid bonds. bile salts emulsify the fats to allow for their solution as micelles in the chyme and to increase the surface area for the pancreatic lipases to operate.
rna and dna are hydrolized by the pancreatic enzymes (ribonucleases, deoxyribonucleases) into nucleic acids, which are further broken down to purine and pyrimidine bases and pentoses, by enzymes in the intestinal mucosa (nucleases).
once the voluntary signal to defecate is sent back from the brain, the final phase begins.
key terms
peptidase: any enzyme that catalyzes the hydrolysis of peptides into amino acids; a protease.
amylase: any of a class of digestive enzymes that are present in saliva and that break down complex carbohydrates, such as starch, into simple sugars, such as glucose.
hydrolysis: the degradation of certain biopolymers (proteins, complex sugars) by the chemical process that results in smaller polymers or monomers, such as amino acids or monosaccharides.