Digestion Flashcards
(13 cards)
Digestion
the process of food being broken down into substances that can be absorbed and used by the body for energy, growth and repair to build new tissue.
Mechanical Digestion
The use of force such as chewing or movements of the stomach or intestines to break down the food. this process begins in the mouth as the teeth tear and grind the food into smaller pieces that can be swallowed without choking.
chemical digestion
the breakdown of food using chemicals such as enzymes and acids
what is enzymatic hydrolysis?
a chemical digestive process that breaks down food by breaking the bonds that hold the molecular “building blocks” within the food together. a reaction occurs when an enzyme incorporates a water molecule across the bond, allowing it to break.
role of the salivary glands in digestion after food is placed in the mouth
the 3 pairs of salivary glands secrete saliva, which contains enzymes salivary amylase. saliva helps lubricate food making it easier to chew and form soft, moist bundle called a bolus. This prepares the food from swallowing and ensures it moves down the digestive track smoothly.
the role of the tongue in digestion after food is placed in the mouth
it mixes food with saliva to form a bolus and pushes it towards the sphincter allowing it to pass into the oesophagus lingual lipase begins digesting triglycerides and epiglottis causes the trachea to prevent food from entering the windpipe during swallowing.
explain how food is assisted in its passage down the oesophagus
food enters the oesophagus goes down by a rush of saliva and peristalsis, which are wave like muscle contractions. these movements pushes the bolus towards the stomach where a muscular value at the base of the oesophagus opens to allow the bolus to enter the stomach
outline the chemical actions that take place when food enters the stomach
the bolus enters the stomach, the walls contract forcefully to further break down the food and churn the bolus into a liquefied mass called chyme. the stomachs acidic environment, with a pH of 1.5-2.5 is created by hydrochloric acid which helps destroy bacteria and aids in nutrient extraction from food. The acidic environments activates the enzyme pepsin which begins the digestion of proteins
Identify and describe the role of 2 enzymes released by the pancreas in the enzymatic hydrolysis of protein
-protease - splits proteins into separate amino acids
-trypsin- involved in breaking down protein into amino acids.
what’s the role of the liver in the digestive process
the liver produces bile, which helps break down fats by turning them into smaller droplets making it easier for enzymes to digest fats. Bile is stored in the gall bladder and released into the duodenum. Liver also processes nutrients from small intestine and helps store glucose and remove toxins.
describe the changes that occur to the following sugars in the small intestine
sucrose- it broken down into glucose and fructose by the enzyme sucrase. these simpler sugars are later absorbed into the bloodstream.
lactose- broken down into glucose and galactose by the enzyme lactase. these are absorbed into the bloodstream for energy.
maltose - broken down into glucose by the enzyme maltase. its then absorbed into the bloodstream for use by the body.
what happens to any indigestible matter once it enters the large intestine
in the large intestine the water is absorbed and gut bacteria ferment fiber for colon health. resulting in faces removed from body muscular contractions.
outline the role of gut microbiota in the large intestine.
it breaks down soluble and insoluble dietary fibre through fermentation. this produces short-chain fatty acids that helps maintain the health of the epithelial cells lining the colon. dietary fibre is not absorbed into the bloodstream.
