Digestion And Enzymes Flashcards
What is the purpose of the mouth in the digestive system ?
Mastication. Teeth to mechanically break down food.
What does mastication mean ?
Chewing and the process by which food is crushed and ground by the teeth.
What is the purpose of the salivary gland in digestion ?
Produces salivary amylase enzymes to hydrolyse starch into maltose.
What is the purpose of the oesophagus in digestion ?
Muscular contraction- squeezes good down the mouth to the stomach by a process known as peristalsis.
What is peristalsis ?
The involuntary construction and relaxation of the muscles of the oesophagus creating waves which push the contents of the canal downwards.
What is he purpose of the stomach in digestion ?
Stores and digests food. Muscular sac with an inner layer that produces enzymes that hydrolyse proteins.
What is the purpose of the liver in the digestive system ?
Produces bike salts which emulsify lipids abs allow enzymes to act more quickly when hydrolysing lipids.
What is the purpose of the pancreas in digestion ?
A gland that secretes pancreatic juices containing protease, lipase and amylase
What enzymes do the pancreatic juices contain ?
Protease
Lipase
Amylase
What is the purpose of the large intestine in digestion ?
Absorbs water from waste.
What is the purpose of the small intestine in digestion ?
Long muscular tubes. Enzymes produces by the walls of the ileum are folded into villi giving a large surface area. Each cell in the wall has microvilli. These further increase the surface area. They also contain of muscular layer for peristalsis.
What is the purpose of the rectum in the process of digestion ?
Stores faeces before it is egested out of the anus.
What does egested mean ??
Excreted.
What is physical digestive breakdown ?
Food is mechanically broken down by structures to five a larger surface area for chemical digestion.
Teeth
Stomach wall churning
Give examples of physical digestive breakdown.
Teeth
Stomach wall churning
What is chemical digestive breakdown ?
Large, insoluble molecules are hydrolysed into smaller, soluble molecules by enzymes.
Where are villus found ?
Small intestine.
Explain features of the villus in the small intestine and why they aid their function.
Large surface area - microvilli further increase the surface area.
1 cell thick- short pathway for diffusion.
Large bold supply enables molecules to move out into the blood maintaining the diffusion pathway.
Describe the function of the muscle layer in the small intestine.
The muscular in the small intestine contract during peristalsis. This moves food down the gut and is a type of mechanical breakdown.
Describe a chemical test you could carry out to find out if a substance if a reducing sugar.
Heat with Benedict’s solution. A red/orange/brown colour indicates reducing sugar.
Which enzymes are used in digestion ?
Lipase - lipids Protease - proteins Amylase - starch Maltese - maltose Lactase - lactose Sucrase - sucrose
Which enzyme are used in protein digestion ?
Endopeptidases - hydrolyse proteins in the middle of a protein molecule.
Exopeptidases - hydrolyse proteins on the end of a protein molecule.
Dipeptidases- hydrolyse peptide bonds in dipeptides.
Give 3 examples of protease enzymes.
Endopeptidases
Exopeptidases
Dipeptidases
In what order are the protease enzymes in protein digestion used.
Endopeptidases
Exopeptidases
Dipeptidases
What type of protease enzyme hydrolysed proteins in the middle of a protein molecule ?
Endopeptidases
What type of protease enzyme hydrolysed proteins on the end of a protein molecule ?
Exopeptidases
What type of protease enzymes hydrolyse peptide bonds in dipeptides ?
Dipeptidases
What enzymes are used in carbohydrate digestion ?
Amylase
Maltase
Sucrase
Lactase
Where does carbohydrate digestion mainly occur?
Ileum of the small intestine
Where is amylase made and what does it do ?
Salivary gland and pancreas
Hydrolysed starch into maltose.
Where is maltase made and what does it do ?
It is made in the ileum and is a membrane bound disaccharide.
Hydrolysed maltose into glucose.
Where is sucrase produced and what does it do.
Ileum of the small intestine.
Hydrolysed sucrose into glucose and fructose.
Where is lactase produced and what does it do.
Ileum of the small intestine.
Hydrolysed lactose unto glucose and galactose.
What chemicals are used in lipid digestion.
Bike salts
Lipase enzymes.
What do bike salts do and where are they produced?
Liver
Split up lipids into tiny droplets called micelles by a process of emulsification.
Where are lipase enzymes produced and what do they do ?
Pancreas
Hydrolyse triglycerides into fatty acids and monoglycerides.
