Enzymes + Energy Carriers Flashcards
metabolism
the sun of all chemical reactions in the body
solar energy
energy from the sun
cellular energy
energy stored in the bonds of biomolecules
enzymes : definition
Enzymes are catalysts made of protein, they speed up a reaction without being used up themselves in the reaction
Enzymes are biological catalysts
Enzyme structure
- made of protein
- 3D shape
- folded
Substance enzyme acts on is a:
Substrate
Substance enzyme forms is a:
Product
Features of Enzymes
- Enzymes are made of protein
- Enzymes work because they have the correct shape to fit the substrate
- Enzyme reactions are reversible
Catalyst : Definition
speeds up a reaction without being used up in the reaction
Catabolic Enzymes
Amylase
- Produced by the salivary glands in mouth and pancreas and convert starch to maltose
- When seeds germinate, the enzyme amylase converts starch in the seed to maltosez
Anabolic Enzymes
- DNA polymerase is an enzyme found in both plants and animals that forms and repairs DNA.
Converts simpler molecules into more complex ones
Anabolic: Definition
Join small molecules into large molecules (Eg:) Photosynthesis
Catabolic: Definition
Large molecules are broken down to small molecules (Eg:) Respiration
Factors affecting Enzyme Activity
Temperature
pH
Substrate concentration
Enzyme concentration
Activation energy
A chemical reaction needs a certain amount of energy for the reaction to happen
Enzymes lower the activation energy therefore reactions happen quicker
Denatured Enzyme: Definition
When the shape of the active site is altered/changed thus, rendering it impossible for the substrate to attach to the active site
Irreversible
Bio processing
is the use of enzyme-controlled reactions to produce a product
Bioreactor
a vessel or contain in which living cells or their products are used to make a producy
Temperature: Affect on enzymes
At low temps ice forms, liquids become solids and enzymes can’t work
As temperature increases molecules start to move and bump into each other cause the rate of reaction to increase.
Optimum temp: Human enzymes
37°C
Optimum temp: Plant enzymes
20°C - 25°C
Optimum Activity: Definition
This is when the enzyme works best or the rate of enzyme activity is at its highest
Temperature Experiment: Enzyme
Catalase (celery)
Temperature Experiment: Substrate
Hydrogen Peroxide
H2O2
Temperature Experiment: Product
H2O (water) + O2 (oxygen)
Temperature Experiment: How to measure rate of enzyme activity?
Using washing up liquid to see the bubbles/foam per minute
pH Experiment: Enzyme
Catalase
pH Experiment: Substrate
Hydrogen Peroxide
H2O2
pH Experiment: Product
H2O (water) + O2 (oxygen)
pH Experiment: How to measure rate of enzyme activity?
Washing up liquid and bubbles of oxygen after one min
Immobilised Enzyme Experiment: Preparing Enzyme
Add sodium alginate to water in beaker.
Stir until smooth paste.
Add yeast to water in second beaker.
Stir.
Dissolve calcium chloride in water in large beaker.
Mix alginate and yeast.
Add drops of mixture to the calcium chloride using a syringe.
Run under tap water when ready to remove any yeast.
Immobilised Enzyme Experiment:
Application of immobilised enzyme
Pour beads into a separating funnel.
Use straw etc to prevent beads from blocking funnel.
Add yeast to water and pour into second separating funnel (CONTROL).
Dissolve sucrose in water and add to both separating funnels.
Use CLINISTIX STRIPS to test for glucose
Benefits of immobilised enzyme
- They may be reused
- They’re easy to separate from the product
- The production process is cheaper than if free enzymes were used
- They’re often more stable than natural enzyme
Methods of Immobilising enzymes
- Attached to each other
- Attached to insoluble supports
- Enclosed within a membrane or gel
Immobilised enzyme: Definition
enzymes that are attached, or fixed to each other or to an inert material
Uses of Immobilised Enzymes
Produce fructose (sweetener) from glucose.
Convert Penicillin to different forms.
Produce sweet-tasting sugars from lactose.
Temperature Enzyme Experiment: Method used to vary temperature
Water bath on hot plate
Thermometer
pH Enzyme Experiment: Mehod used to vary pH
Different pH buffers
Eg: 4, 9, 12
SUMMARY: to test effect of temperature on rate of enzyme activity
Mix blended celery (catalase), hydrogen peroxide, pH buffer 9 and washing up liquid
Note volume of foam formed after two mins at different temperatures
SUMMARY: to test effect of pH on rate of enzyme activity
Mix blended celery (Catalase), hydrogen peroxide, pH buffer (???) and washing up liquid
Note volume of foam formed after two mins at different pH values
SUMMARY: Sucrase is immobilised by:
Mixing yeast solution with sodium alginate solution
Adding beads of the mixture to calcium chloride solution
Rinsing hardened beads in sieve
SUMMARY: Application of immobilise enzyme is shown by:
Adding sucrose solution to immobilised yeast in a separating funnel
Testing for the production of glucose
Clinistix strips
Active Site: Definition
The part of an enzyme that combines with the substrate
Induced fit model:
Substrate causes active site to change shape slightly
Enzyme and substrate for a temporary enzyme-substrate complex
Substrate is altered
Enzyme remains unchanged and active site returns to original shape
Enzyme Specificity: Definition
Means that each enzyme will react will one particular substrate
Optimum pH: Definition
The pH in which the enzyme works best at
Causes of Denaturation:
High temperatures
pH values outside of optimum pH
Some chemicals
Radiation
ADP
Name
Adenosine Diphosphate
ATP
Name
Adenosine Triphosphate
Energy Carriers: Definition
carry energy in cellular reactions (metabolism)
Energy Carriers: Photosynthesis: Low Energy
ADP
NADP
Energy Carriers: Photosynthesis: High energy
ATP
NADPH
Energy Carriers: Respiration: Low energy
ADP
NAD
Energy Carriers: Respiration: High energy
ATP
NADH
ADP
Makeup
Made of the base adenine, 5 carbon sugar called ribose and two phosphate groups
Low energy molecule
ATP
Makeup
Made of the base adenine, 5 carbon sugar called ribose and three phosphate groups
High energy molecule due to third phosphate
Phosphorylation: Definition
Addition of phosphate
ADP + ENERGY + P = ATP + WATER
~~> ATP + WATER = ENERGY + P
ATP + WATER = ADP + ENERGY + P
~~> ADP + ENERGY + P = ATP + WATER
How is the energy in ATP released?
through the breaking of the bond of the third phosphte
What processes are ADP and ATP used in?
Respiration
Photosynthesis
NADP+
low energy molecule
NADPH
High energy molecule
used to form glucose in photosynthesis
When NADPH breaks down…
it released high energy electrons and hydrogen
NADPH = NADP+ + 2 ELECTRONS + H+
NADP+ + 2 ELECTRONS + H+ = NADPH
What process are NADP+ and NADPH used in?
Photosynthesis
NAD+
low energy
NADH
High energy
NAD into NADH how?
NAD+ can combine with two high energy electrons and a proton to form NADH which is very high in energy
What do NADH and NADPH provide for reactions in cells
electrons, protons and energy used by cells
Explain the role of ATP
ATP is the most widely distributed high energy compound within the organism and powers virtually every activity of the call and organism
It is used to build complex molecules, contract muscles, generate electricity in nerves etc
Describe how ATP is formed from ADP + P
Charging ADP to form ATP is called phosphorylation
In eukaryotes this can occur in special energy producing structures called mitochondria
Explain the role of NADP+ in trapping and transferring electrons and hydrogen ions in cell activities
NADP+ can combine with two high energy electrons and a proton to form NADPH
NADPH is a very high energy molecule and this energy is used to form glucose in photosynthesis
yeast contains what enzyme
sucrase
