Enzymes. Biological catalysts.
What is a catalyst?
A catalyst is a ______________ that can ______________ up a reaction without getting __________.
Look at the diagram below and label the numbers 1 to 5 with the correct descriptions.
1 2 3 4 5
An important point about enzymes is that they are very specific about what they can catalyse. The reason for this lies in the active site present in the enzyme . . .
Active sites
______ _______ are cracks or hollows on the surface of the enzyme caused by the way the __________ folds itself up into its tertiary structure. Molecules of just the right shape, and with just the right arrangement of attractive groups can fit into these active sites. Other __________ won't fit or won't have the right groups to bind to the ___________ of the active site.
The usual analogy for this is a ______ fitting into a lock. For the key to work properly it has to fit exactly into the lock.
In chemistry, we would describe the molecule which is actually going to react as the reactant. In biology and biochemistry, the reactant in an enzyme reaction is known instead as the ________.
Protein surface Active sites key molecules substrate Make notes in your book from the ppt, about the different enzymes, where they are produced and what they do.
Enzymes used in the breaking down of carbohydrates
S molecules are the storage structure used by plants. Basically they are long, often branched chains of molecules. Glucose (a sugar) is required by the body to provide . Starch cannot be absorbed into the blood stream because the molecules are In the mouth, an enzyme called amylase starts the digestion of starch by breaking it down into .Maltose molecules are also to be effectively absorbed. Amylase from the pancreas ( ) mixes with starch in the small intestine to produce more maltase. The small produces an enzyme called____________
that breaks down maltose to glucose. The molecules are then taken into the blood and transported around the body to provide energy
Glucose too small protein Starch maltose potatoes pancreatic
amylase intestine Energy too big Sugar Salivary amylase
too big maltase
Enzymes used in the breaking down of proteins
Proteins are essential in the diet for _________________________
Proteins are large branched molecules (_______________________) found in all types of meat and soya beans.
Proteases are enzymes that digest proteins examples are________________.
Proteins are too ________ to be absorbed into the blood stream.
Trypsin is produced in the ___________.
Trypsin is released into the __________________ and breaks down proteins to form peptides.
Peptidase is produced by the ________________.
Peptidase breaks down peptides into individual _________________ that are easily absorbed.
What pH do you think these enzymes work best in? ______________
Trypsin & Peptidase / small intestine / growth and tissue repair / large / small Liver / Pancreas / Chains of amino acids/ amino acids / acid / alkaline / neutral
Cross out the wrong answers...
Fats and oils are essential to our diet/ food / suntan.
They are used in the production / destruction / recycling of cell membranes, for storing energy and for heat insulation.
Lipase is produced in the pancreas/ stomach / oesophagus.
The stomach pH is too acidic / alkaline / salty for it to work.
Bile is needed to make a paint / emulsion / mixture.
Bile is made in the stomach / kidneys / heart / liver.
One product of fat digestion is glucose / glycerol / gluey acid.
Fatty acids & glycerol are easily absorbed / secreted / drip into the blood stream
