The Human Digestive System Flashcards
The digestive system is an example of an organ system in which…?
Several organs work together to digest and absorb food.
Enzymes are…?
SPECIFIC
Enzymes _________ specific reactions in ___________ organisms due to the shape of their ________ site
Catalyse
Living
Active
Digestive enzymes convert food into small soluble ___________ that can be absorbed into the _____________
Molecules
Bloodstream
Carbohydrases break down carbohydrates into…?
Simple sugars
Amylase is a carbohydrase which breaks down…?
Starch
Pro teases break down proteins into…?
Simple sugars
Lipases break down lipids into…?
Glycerol and fatty acids
The products of digestion are used to build new ______________, lipids and _________. Some _________ is used in respiration.
Carbohydrates
Proteins
Glucose
Where is bile made and stored?
Made in liver
Stored in gall bladder
Why is bile alkaline?
To neutralise hydrochloric acid from the stomach
What does bile do to fat?
Emulsifies the fat to form small droplets which increases the surface area.
What increases the fat breakdown of lipase?
Bile and lipids
The alkaline conditions and large surface area
What is metabolism?
The sum of all the chemical reactions in the body or the cell
Enzymes form a ____ and the reactants(__________) go into the site. The part of the enzyme to which the reactant ______ is called the ______ ______
Site
Substrates
Binds
Active site
What is the rate calculation for chemical reactions?
Time taken
Explain the lock and key theory
In the way a key fits into a lock, a substrate is thought to fit into an enzymes plastic site. The enzyme is the LOCK, the reactant is the KEY
Where is amylase produced?
Pancreas
Mouth
Small intestine
Where are proteases produced?
Pancreas
Small intestine
Stomach
Where are lipases produced?
Pancreas
Small intestine
Where are caebohydrases produced?
Pancreas
Small intestine
What pH does amylase work at?
pH 7
What pH do lipids work at?
pH 7/8
What pH do proteases work at?
pH 2 in the stomach
pH 7/8 in the pancreas/small intestine
What pH do carbohydrases work at?
pH 7/8
Describe the nature of enzyme molecules and relate their activity to temperature and pH changes
Enzymes are proteins.
They are sensitive to temperature and pH. At high temperatures, they get denatured and at lower temperatures, they don’t work as well as they would at their optimum.
