enzyme action Flashcards
during a chemical reaction
a new substance is formed as a substance changes from one form to the other
the substance of which the enzyme acts is known as
the substrate
enzymes
protein that has a particular shape to enable it to perform its speciifc function
enzymes are substrate specific meaning
a specific enzyme can only act on a specific substrate
active site
the part of the enzyme where substrate molecules bind and a chemical reaction takes place. The active site is made up of amino acid residues that establish temporary bonds with the substrate (binding site) as well as residues that catalyse that substrate’s reaction (catalytic site).
the substrate molecule fits into
the enzyme’s active site as a key fits into a lock to ensure the specificity of the enzyme then a temporary enzyme substrate complex is formed.
anabolic reaction in an active site
Anabolic reactions utilize energy to synthesize larger molecules from smaller units. Example- formation of glycogen from simple sugar molecules is an anabolic reaction.
temperature
enzymes are sensitive to temperature change. low temperatures make enzyme temporarily inactive .
the temperature at which enzymes work the best is known as their optimum temperature which is
35 to 40 degrees in humans (body temperature is 37)
at high temperatures
usually above 45 the shape of the enzyme begins to change and the substrate no longer fits into the active site. The enzyme can’t perform its function. the enzyme denatures
denaturation is an irreversible process
when the enzyme denatures it cannot return to its proper shape when the temperature is lowered again.When the enzyme becomes inactive as a result of low temperature it can become active again once the temperature rises.
optimum ph
each enzyme has a narrow ph range within which it can function. some enzymes qork optimally in acidic medium whereas others in a neutral or alkaline medium. enzymes denature at extreme ph levels
properties of enzymes
1) spherical proteins
2) sensitive to chnages in temperatures in high temperature the enzyme denatures whereas low tempratures to make temporarily inactive
3)substrate specific
$4)can be used over and over again
5) a small amount of enzyme can change a large amount of subtrate
enzymes in everyday life
biological washing powder such as bio tex/classic contain enzymes that break up/remove biological stains. these enzymes usually act on proteins and are known as protease stains caused by blood/sweats consist of difficult porteins to remove therefroe the enzyme in the washing powder break down the proteins down into smaller soluble molecules easily removed by cleaning agents
catalase
enzyme found in most animal and plant cells that accelerates the breakdown of hydrogen peroxides into water and oxygen. oxygen is released during this reaction as bubbles
saccharides
Sugars
Soluble in water
monosaccharide
A simple sugar
The chemical formula of
glucose is:
C6H12O6
monosaccharides
These are simple
sugars.
They all have a single
ring, six sided
structure as shown in
the picture
alongside-this picture
is called a structural
formula.
Glucose and fructose
are examples of
monosaccharide’s.
A monosaccharide is the simplest form of
carbohydrates.
In other words they are the smallest units that
more complex carbohydrates are made up of.
The smallest or simplest unit of any substance is
called its building block.
Another word for building block is monomer.
The monomer of a carbohydrate is the
monosaccharide.
monomer
is a building block or simplest
unit of a more complex substance.
Carbohydrates have three main functions.
Energy. They are an important source of
energy. During cellular respiration glucose is
broken down to release energy.
Storage. They serve as storage substances
for energy. For example in the human body
extra glucose (energy source) is converted into
glycogen and stored in the liver.
Building materials. For example they
supply cellulose for the making of plant cell
walls.
nucleic acid
Nucleic acids are organic compounds found
in the cells.
two types of nucleic acid
They are:-
Deoxyribonucleic acid
Ribonucleic acid
