ORGANISATION
Tissues & Organs
T
● issue - A group of specialized cells with a similar structure and function
● Organs - A group of tissues that work together to carry out a specific
function
● Organ System - A group of organs that work together to carry out a specific
function and form organisms (eg. the digestive system)
Multicellular organisms (like humans) have many levels of organization that are:
Cells
↓
Tissues
↓
Organs
↓
Organ Systems
↓
Organisms
Enzymes
● E
nzymes - A biological catalyst (a substance that increases the rate of
reaction without being used up)
HE SHAPE:Every enzyme has an active site and a uniquesubstrate that fits into
T
it. This is because enzymes are extremely specific and each one will only catalyse
one specific reaction.
PTIMUM: Enzymes need the correct temperature andpH to work. Changing
O
either will change the rate of the reaction. If the either goes too high or too low
then the shape of the active site will change and the substrate will no longer fit.
The enzyme will then be ‘denatured’.
Enzyme Practical (Required Practical Nº4)
1 . P lace one drop of iodine solution into each place on the spotting tile.
2. Set up water baths for every temperature you want to test
3. Measure out 5 cm³ of starch solution, using the measuring cylinder or
syringe, into some test tubes.
4. Place one test tube of starch solution into each water bath.
5. Repeat step 3 & 4 with 1cm³ of amylase solution
6. Leave the test tubes in the water baths until the contents of each test tube
have reached the correct temperature on the thermometer
, 7. W hen the contents of the test tubes in one water bath have both reached
the required temperature, make a note of this temperature. Then, carefully
pour the amylase solution into the test tube with the starch solution and
mix with the glass rod.
8. Remove one drop of the mixed solution on the end of the glass rod and
place on the first depression of the spotting tile with the iodine solution.
This is ‘time zero’.
9. Immediately start the stop clock.
10. Using the glass rod, remove one drop every minute and place onto the
iodine solution in the next depression on the spotting tile.
11. Continue until the iodine solution no longer turns black. This indicates that
the starch has been broken down.
12. Record the temperature of the water bath and the time taken for the
starch to be broken down in a table.
Digestive Enzymes
igestive enzymes break down big molecules that are too large to be absorbed
D
into the bloodstream; starch, proteins and fat. These are broken down:
● Starch ( + amylase enzyme) → Maltose (and other sugars)
○ Amylase enzymes are made in the salivary glands, pancreas and
small intestine
● Proteins ( + protease enzyme ) → amino acids
○ Protease enzymes are made in the stomach, pancreas and small
inteastine
Lipids ( + lipase enzyme ) → glycerol and fatty acids
●
○ Lipase enzymes are made in the pancreas and small intestine
Bile
● P roduced in the liver, stored in the gall bladder and released in the small
intestine
● The hydrochloric acid in the stomach makes the pH too acidic for enzymes
to work properly in the small intestine. The bile is alkaline and therefore
neutralises the HCl.
The digestive system
Structure Function
Mouth alivary glands produce the amylase enzyme which
S
starts the break down of starch
Gullet (oesophagus) Moves the ingested food to the stomach
Stomach ummels food with muscular walls. Produces pepsin
P
(protein enzyme) and hydrochloric acid to kill bacteria
and provide the optimum pH for protease to work
Tissues & Organs
T
● issue - A group of specialized cells with a similar structure and function
● Organs - A group of tissues that work together to carry out a specific
function
● Organ System - A group of organs that work together to carry out a specific
function and form organisms (eg. the digestive system)
Multicellular organisms (like humans) have many levels of organization that are:
Cells
↓
Tissues
↓
Organs
↓
Organ Systems
↓
Organisms
Enzymes
● E
nzymes - A biological catalyst (a substance that increases the rate of
reaction without being used up)
HE SHAPE:Every enzyme has an active site and a uniquesubstrate that fits into
T
it. This is because enzymes are extremely specific and each one will only catalyse
one specific reaction.
PTIMUM: Enzymes need the correct temperature andpH to work. Changing
O
either will change the rate of the reaction. If the either goes too high or too low
then the shape of the active site will change and the substrate will no longer fit.
The enzyme will then be ‘denatured’.
Enzyme Practical (Required Practical Nº4)
1 . P lace one drop of iodine solution into each place on the spotting tile.
2. Set up water baths for every temperature you want to test
3. Measure out 5 cm³ of starch solution, using the measuring cylinder or
syringe, into some test tubes.
4. Place one test tube of starch solution into each water bath.
5. Repeat step 3 & 4 with 1cm³ of amylase solution
6. Leave the test tubes in the water baths until the contents of each test tube
have reached the correct temperature on the thermometer
, 7. W hen the contents of the test tubes in one water bath have both reached
the required temperature, make a note of this temperature. Then, carefully
pour the amylase solution into the test tube with the starch solution and
mix with the glass rod.
8. Remove one drop of the mixed solution on the end of the glass rod and
place on the first depression of the spotting tile with the iodine solution.
This is ‘time zero’.
9. Immediately start the stop clock.
10. Using the glass rod, remove one drop every minute and place onto the
iodine solution in the next depression on the spotting tile.
11. Continue until the iodine solution no longer turns black. This indicates that
the starch has been broken down.
12. Record the temperature of the water bath and the time taken for the
starch to be broken down in a table.
Digestive Enzymes
igestive enzymes break down big molecules that are too large to be absorbed
D
into the bloodstream; starch, proteins and fat. These are broken down:
● Starch ( + amylase enzyme) → Maltose (and other sugars)
○ Amylase enzymes are made in the salivary glands, pancreas and
small intestine
● Proteins ( + protease enzyme ) → amino acids
○ Protease enzymes are made in the stomach, pancreas and small
inteastine
Lipids ( + lipase enzyme ) → glycerol and fatty acids
●
○ Lipase enzymes are made in the pancreas and small intestine
Bile
● P roduced in the liver, stored in the gall bladder and released in the small
intestine
● The hydrochloric acid in the stomach makes the pH too acidic for enzymes
to work properly in the small intestine. The bile is alkaline and therefore
neutralises the HCl.
The digestive system
Structure Function
Mouth alivary glands produce the amylase enzyme which
S
starts the break down of starch
Gullet (oesophagus) Moves the ingested food to the stomach
Stomach ummels food with muscular walls. Produces pepsin
P
(protein enzyme) and hydrochloric acid to kill bacteria
and provide the optimum pH for protease to work
