B2 - Organisation Flashcards
What do the TEETH do and What does the SALIVA contain ?
Break down food Mechanically.
Saliva contains Amylase
STOMACH
Contains Hydrochloric Acid and Enzymes that break food down Chemically.
What does the LIVER produce ?
- The Liver Produces Bile
- Bile is stored in the Gall Bladder before going to the small intestine.
What does BILE do ?
Emulsifies Lipids to form Droplets, Increasing their Surface Area
What does the PANCREAS do ?
- Secretes Amylase
- Amylase breaks down Starch into Glucose in the Small Intestine.
What is WATER ABSORBED into ?
Into the Bloodstream in the Large Intestine.
Where are NUTRIENTS ABSORBED ?
- Nutrients are Absorbed into the Bloodstream by the Villi in the Small Intestine.
eg. Glucose
What are ENZYMES ?
- Enzymes are Special Proteins that act as Biological Catalysts
- Enzymes often break down molecules into shorter ones.
AMYLASE BREAKS DOWN…
Starch into Glucose
What do CARBOHYDRATES BREAK DOWN into ?
Break down into simple sugars.
What do PROTEASES BREAK DOWN ?
Break down Protein into amino acids.
What do LIPASES do?
Break down Lipids into Glycerol and Fatty Acids.
ENZYMES are SPECIFIC so they ONLY BREAK DOWN…
Substrates that fit their Active Site.
What does ENZYME ACTIVITY increase with ?
- Increases with Temperature until the Enzyme Denatures.
AND - The same is true if pH is too High or Low.
OPTIMUM IS…
The Condition for Max Rate/Activity.
ENZYME PRACTICAL - INDEPENDENT/DEPENDENT VARIABLE and CONTROLS
Independent Variable : Temperature or pH
Dependent Variable :
Time for Substrate to be Broken Down
Controls :
Volumes of Reactants
Temperature if changing pH
pH if changing Temperature
ENZYME PRACTICAL
- Measure out the Enzyme and Substrate.
- Place separately in a Water Bath, along with Buffer Solution ( If changing the pH )
- Prepare a Spotting Tile with Iodine Drops
- Mix the Reactants together and start a Timer.
- Every 10 seconds, remove a Drop of the Mixture and put in a Dimple of Iodine.
- If it changes Colour = Starch still Present.
- Once all the Starch is Broken Down, it will no longer change Colour
- Repeat for different Temperatures/pH Buffer Solutions.
- Plot these times against Temperature/pH and draw a LOBF.
Optimum Condition lies between the Two Lowest Points.
ENZYME PRACTICAL - CONTROLS
Volumes of Reactants
Temperature if changing pH
pH if changing Temperature
What does the STARCH FOOD TEST do ?
Turns Iodine’s Solution from Orange to Black
What does the SUGARS FOOD TEST do ?
Turns Benedict’s Solution from Blue to Orange
What does the PROTEIN FOOD TEST do ?
Turns Biuret’s Reagent from Blue to Purple
What does the LIPIDS ( FATS ) FOOD TEST do ?
Turns Cold Ethanol Cloudy
What do ALVEOLI (AIR SACS) HAVE and What does it ALLOW ?
A Large Surface Area
To allow Gas Exchange to occur at a fast rate