Pages in this set

Page 1

Preview of page 1
Akash G 12M

1.0 - Disease
1.1 Pathogens:

Pathogens are disease causing microorganisms
Disease is the symptoms displayed on a person following an infection, a malfunction of the body or mind
Infectious Disease: Caused by bacterium, virus, fungum transferred from one person to another
Non Infectious Disease: A disease that…

Page 2

Preview of page 2
Akash G 12M
Pathogens cause disease by:
Damaging host tissue (inhibit the synthesis of DNA,RNA and proteins ­ may break down the membrane of the
host cell)
Produce toxins (have various effects such as increased water loss from cholera bacteria)

1.2 Data and Disease:

Epidemiology is the study of the…

Page 3

Preview of page 3
Akash G 12M

2.0 - Enzymes and the Digestive System
2.1 Enzymes and digestion:

The digestive system is made up of one long tube which is an interface to the environment as food passes into the
body through it; which contains glands that produce enzymes.

Major parts of the digestive…

Page 4

Preview of page 4
Akash G 12M
There are two types of digestion:
1. Physical breakdown
2. Chemical digestion

1. Physical Breakdown:
o Food is broken down into smaller pieces by the teeth
o Makes it possible to ingest, and increases surface area for chemical digestion
o Churning of food by stomach muscles…

Page 5

Preview of page 5
Akash G 12M
2.2 - Carbohydrates ­ Monosaccharides

These are made up of a chain of individual monomers
Repeating monomer units is called a polymer
In carbohydrates, the basic monomer is sugar ­ a saccharide
o A single monomer = monosaccharide
o A pair of monosaccharides = disaccharide

Page 6

Preview of page 6
Akash G 12M
2.6 Enzyme Action
Enzymes are globular proteins that act as biological catalysts. They alter the rate of a chemical reaction without
undergoing permanent changes.

Enzymes as catalysts:
For a reaction to take place normally, such as:
Sucrose + Water Glucose + Fructose
The sucrose and water molecules…

Page 7

Preview of page 7
Akash G 12M
Lock and Key Hypothesis:

In the same way that a lock fits a key precisely, the substrate is thought to fit the enzyme perfectly. This helps
to explain the specific nature of the enzyme.
However: this suggests that the active site is a rigid structure, but scientists…

Page 8

Preview of page 8
Akash G 12M
Enzymes and Reaction Rates:

A rise in temperature increases the kinetic energy of molecules
This means that molecules move around more rapidly, and collide with each other more often
This increases the likelihood of a successful collision taking place
However, a rise in temperature also causes…

Page 9

Preview of page 9
Akash G 12M

3.0 Cells and their movement
Cell structure 3.1:

The limitation of a light microscope is that there is a poor resolution. This can be solved by using a beam of electrons,
because they have a shorter wavelength.

Magnification = Size of an image / Size of an…

Page 10

Preview of page 10
Akash G 12M
Microscopy (3.2):

Through a microscope you can see the field of vision, eyepiece graticule (smaller scale) and the stage micrometer

Transmission Electron Scanning Electron
Microscope (TEM) Microscope (SEM)
Maximum 500 000 x 100 000 x
Resolution 0.2nm 2 nm
Advantages Magnifies objects over Better resolution and…




Part of section 5 on the heart is missing? 



^^^^ :( this looks sooo good appart from the fact the most of section 5 is missing

Similar Biology resources:

See all Biology resources »