Pages in this set

Page 1

Preview of page 1
Topic 2: Enzymes and The Digestive System


Topic 2.1 Enzymes and Digestion

Major Components of the digestive system
Oesophagus
Responsible for movement of food from the mouth to
the stomach
Adapted for transport
Consists of a thick muscular wall
Stomach
Muscular sac lined with a layer that secretes enzymes
and…

Page 2

Preview of page 2
Topic 2: Enzymes and The Digestive System


Breaking down of components by physical movement, such as the churning in the stomach by muscles
movements, and chewing of food
Increases surface area
Chemical Digestion
Breaking down large molecules into much smaller molecules with the addition of water.
Hydrolysis ­ the function…

Page 3

Preview of page 3
Topic 2: Enzymes and The Digestive System


2.3 Carbohydrates ­ Disaccharides and Polysaccharides
Monosaccharides combine to form disaccharides as a result of condensation reactions, which form
glycosidic bonds.
The formation of polysaccharides is a result of multiple condensation reactions
Condensation reactions remove water molecules; to break down polysaccharides, hydrolysis adds…

Page 4

Preview of page 4
Topic 2: Enzymes and The Digestive System


The epithelial lining of the small intestine secretes maltase, which is used for the hydrolysis of maltose
into -glucose.

Digestion ­ Disaccharides

Sucrose
Found contained in cells, which is physically
broken down by the teeth.
Epithelial lining produces sucrase which is used
to…

Page 5

Preview of page 5
Topic 2: Enzymes and The Digestive System


Hydrolysis breaks down the peptide bonds (similar to that of carbohydrates)




Primary Structure ­ Polypeptides

Amino acid monomers joined together from a number of condensation reactions (condensation
polymerisation)
Formation of a polypeptide, which is the primary structure of a protein.
There is no…

Page 6

Preview of page 6
Topic 2: Enzymes and The Digestive System


Hydrogen bonds - these are found in high proportions to the other bonds, but these are the most easily
broken bonds.

Quaternary Structure

These are proteins that contain prosthetic (non-protein groups)
An example of a quaternary structure for a protein is haemoglobin, where…

Page 7

Preview of page 7
Topic 2: Enzymes and The Digestive System


One important limitation that was recognised was the fact that a lock (in this case, a substrate) is of a rigid
structure.
From the evidence given by scientists, it was observed that a substrate was able to place itself into an
area on…

Page 8

Preview of page 8
Topic 2: Enzymes and The Digestive System




Figure 2: Observation of Disappearance
The initial reading will be high, as the reaction will not have begun.
Will begin to plateau at lower points, as the reactant is being used (and converted into products)
As the reaction progresses, the reactant will be…

Page 9

Preview of page 9
Topic 2: Enzymes and The Digestive System


When there is a low substrate concentration, there are empty active sites, and so the rate of reaction is not as
efficient as it can be, as the active sites are not being used to its full extent.

When the substrate concentration is…

Page 10

Preview of page 10
Topic 2: Enzymes and The Digestive System




Shivani BarotPage 10
13F

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »