Aperson had bread and butter for his breakfast. trace the changes in the main components of these during its passage through the alimentary canal

When the bread and butter is in mouth, mechanical digestion starts. The size of the food gets reduced and it mixes with saliva for easy swallowing. The salivary amylase in saliva begins the digestion of starch in the bread. This is the start of chemical digestion. When the undigested bread and butter reached the stomach, lower esophageal sphincter relaxes and allow the chewed food to enter. The gastric secretions containing HCl, acts on the undigested food to produce chime. HCl kill the microorganism on the food and also denatures the protein and later attacked by digestive enzyme pepsin. Pepsin breakdown protein in the bread, butter . Later on gastric lipase begins to digest fat present in butter. Digestion of the starch in bread does not occur in the stomach because the salivary amylase that began chemical digestion in mouth became inactive in the presence of HCl. Further the chime enters the small intestine where bile secreted by the gall bladder emulsifies the fat and break into small globule which helps in fat absorption.

the rocks are classified by the geological process they are formed by. the three main groups of rocks are igneous, metamorphic, and sedimentary. minerals are not they are classified under the chemical classes they are in. these groups include silicates, sulfates and carbonates.