The Digestive System Flashcards
Teeth
Mechanical breakdown of food in the mouth
Oesophagus
Transport of food to stomach by peristalsis
Ileum
Final digestion and main absorption of nutrients
Anus
Defecation
Gall bladder
Site of bile salt storage
Stomach
Storage and digestion of food
Tongue
Mixes food with saliva
Pancreas
Secretes insulin, glucagon and digestive enzymes
Duodenum
Further digestion and some absorption of nutrients
Mouth
Starting point of food entering digestive system
Liver
Site of bile production
Colon
Absorption of water, salts and vitamins
Mouth
Class, name, action, source
Carbohydrase
Amylase
Starch-maltose
Salivary gland
Stomach
Class, name, action, source
Protease
Pepsin
Proteins-peptides
Stomach
Small intestine 1
Class, name, action, source
Carbohydrase
Amylase
Starch-maltose
Pancreas
Small intestine 2
Class, name, action, source
Carbohydrase
Maltase
Maltose-glucose
Wall of small intestine
Small intestine 3
Class, name, action, source
Protease
Trypsin
Proteins-protease
Pancreas
Small intestine 4
Class, name, action, source
Protease
Peptidase
Peptides-amino acids
Wall of small intestine
Small intestine 5
Class, name, action, source
Lipase
Lipase
Lipids-glycerol and fatty acids
Pancreas
Active sight of enzymes
Part of the fold in a protein (chain of amino acids) forms the active aight where the substrate will attach
Catalysts
Proteins which speed up biochemical reactions (biological catalysts)
What to enzymes do in a reaction?
In anabolic reactions they speed it up
How do amino acids fold
Depending on the reactions between the amino acids
What is an es
Enzyme substrate
Brief description of how enzymes work
- substrate binds to an active site
- ES complex forms
- the two things bind and this is the reaction
- enzyme changes the shape of the substrate
- substrate no longer fits in active site
- product is released
- enzymes is not changed or used up
How do enzymes speed up reactions
Lowers activation energy and vcan speed up by up to 10^6 x
Factors effecting enzymes activity
Temperature, PH and concentration (of substrates and enzymes)
Example equation of enzymes catalysing
Hydrogen peroxide –> water + oxygen
H2O2 –> H2O + O2
What pH is most effective on an enzyme
7- neutral which is found in our bodies where enzymes are used
What parts break down food
Mouth stomach and duodenum
Where are enzymes produced
Gut wall and pancreas
Where is digested food absorbed
The ileum
Where is water absorbed and faeces stored
Duodenum
Enzyme in salvia
Amylase
Class of enzyme which digest carbohydrates
Carbohydrates
Class of enzyme which digests protein
Protease
Class of enzyme which breaks down lipids
Lipase
Main substances in waste material
Cellulose (fibre), water and bacteria
What does colon do
Absorbs remaining water leaving in faeces
Why use enzymes in industry
Cheaper
Easier
Natural
Reusable
Disadvantage of enzymes in industry
Expensive to produce
Can denature if overheated
Mouth enzyme conversion
Starch to maltose
Perstalsis
Wave like muscle contractions that move food through the digestive tract
Stomach enzyme conversion
Protein to amino acids/peptides
Duodenum enzyme conversion
Starch to maltose to glucose
Protein to peptides to amino acids
Lipids to glycerol and fatty acids
Clump of fat molecules
Globule or droplet
Surface area adaptations in digestive system
Large SA from villi and microvilli
Increases rate of absorption
Concentration gradient adaptations in digestive system
Blood veins inside of intestines blood flows where it is needed
Diffusion distance adaptations in digestive system
Villi walls are 1 cell thick
Capillaries walls are 2 cells thick
Increase speed as short distance
Where is bile made
Liver
What does bile do in digestion
Bile emulsifies the large fat globules and turns into small droplets which increase SA:V so they can be digested faster
Carbohydrates
- Sugars and starches
- Made of carbon, hydrogen and oxygen
- Provide energy for cells
Explain structure of villi
- microvilli are 1mm long
- coated in later of microvilli
- villi has very large SA:V
- capillaries run through and differ in concentration which creates a concentration gradient to encourage blood flow
- walls of capillaries are 1 cell thick so diffusion is fast
- villi have a folded structure which increases SA:V
Examples of simple carbohydrate
Glucose and sucrose
Examples of complex carbohydrates
Starch, glycogen, cellulose
Test for starch
Reddish brown iodine solution turns blue/black with starch
Test for sugar
Blue Benedict’s solution turns orange-red when heated with simple sugars like glucose
How can you determine the energy content of food?
Burning it and using it to heat a measured sample of water- simple version of a calorimeter
Proteins
- Long chains of amino acids
- Contain carbon, hydrogen, oxygen, NITROGEN AND SULFUR
Lipids
- Made of fatty acids and glycerol
- Contain a lot of energy
- Made of hydrogen, carbon and oxygen
Vitamin A role and source
Makes chemicals in retina, protects surface of eye and connective tissue
Fish oils, liver, butter, margarine, carrots
Vitamin C role and source
Connects cells which line surfaces in the body
Fruits (especially citrus) and vegetables
Vitamin D role and source
Helps bones absorb calcium and phosphorus
Sunlights, fish oils, cream, butter
Calcium role and source
Makes bones and teeth
Dairy products, fish, bread, vegetables
Iron role and source
Makes haemoglobin in red blood cells to carry oxygen
Red meat, dark leafy greens, liver, eggs
