Self+and+Non+Self


 * VCE Biology Unit 3: Signatures of life **


 * Area of Study 2: Detecting and responding **

__** Big Idea: Self and non-self **__


 * Learning Activity 1 **
 * Disease – any condition that impairs the normal functioning of an organism
 * Pathogen – an infectious agent that causes disease to another organism
 * Vector – an agent that can transfer a pathogen from one organism to another
 * Virulence – intensity of the effect of the pathogen
 * Resistance – extent to which an organism is affected by a pathogen

Pathogens can be cellular or non-cellular. Pathogens are usually ‘host’ specific and therefore know what species to invade. See figure 7.1 Heinemann Biology 2, page 156. A vector is an agent which carries a pathogen from one agent (organism) to another. Also see Figure 5.1 Nelson Biology 3&4 Bacteria: an organism that causes disease, there are different classifications of bacteria see page 159 Heinemann Biology 2. The Gram stain also on page 159 is a good example of distinguishing the difference between 2 large groups of bacteria. Those bacteria which are Gram-positive are more susceptible to penicillin and the Gram-negative which are less susceptible.



Biochemical Identification of unknown Bacteria: Complete an Investigation Bacteria flow chart as seen on page 161 Heinemman Biology 2, including the presence and results of the gram stain importance and where it can be done to help determine treatment.
 * Experiment: Gram staining of bacteria. **
 * Purpose: ** For students to determine the difference between a gram-positive and gram-negative result in bacteria identification.
 * Materials: ** Follow the procedure guidelines on sheet provided (link below)
 * Procedure: ** Follow the procedure guidelines on sheet provided (link below)
 * [] **

** Learning Activity 2 **


 * 3 major lines of defence **


 * 1) **Physical and chemical barriers** (Non specific) that prevent pathogens from entering the body (skin, mucous membranes)
 * 2) **Non-specific immune response** inside the body (inflammation, lymphatic system, spleen)
 * 3) **Specific immune response** that targets pathogens (antibodies, cell mediated responses)



Heinemann Biology 2


 * Physical and chemical barriers **

** Types of Defence **

 * Non Specific || Specific ||
 * Innate || Ability to recognise a particular target ||
 * Physical || Memory- second exposure produces a larger and more rapid response ||
 * Chemical ||  ||
 * Cellular ||  ||

Summary of bodies defence barriers




 * Non specific defence mechanism inside the body **

The body needs to identify if a cell is self or non-self

MHC – Major histocompatibility complex

• Genetically unique to an individual.



• T-cell receptor binding with MHC marker molecule and antigen

• This activates the T-cell and releases destructive enzymes

Types of non-specific immune responses

• “Unleash” defensive molecules

– Cytokines

– Interferons

– Complement

• “Unleash” cells that kill

– Phagocytes

– Natural killer cells

• Produce a number of protective responses

– Inflammation

– Clotting

– Fever



• Humoral immunity – B-lymphocytes which make antibodies • Cell-mediated immunity – T-lymphocytes which recognise foreign cells – (NB –cytokines act as messengers between cells) • Antigens – molecules that are able to bind to antibodies or T-cell receptors and stimulate production of antibodies • Antibodies – Highly selective – Also called immunoglobulins (Ig) – 5 types (page 192 – need to know these!) • lymphocytes – generic name for white blood cells that respond to antigens
 * Specific immune response **
 * 2 Lines of defence **

Antibodies and antigens, know the difference






 * Activity **

Draw a mind map outlining the different pathways of a human’s immune response, including the 3 lines of defence and the process which each takes to ensure immunity to foreign or non self particles.As the teacher you can decide whether to give them the template of get them to create their own.



Template received from: http://www.biology.lsu.edu/introbio/tutorial/Concept-maps/1002/Immune-system-map.html

Immune System Part 1: Barriers and Non Specific Defenses [] <span style="color: #000000; font-family: Arial; font-size: 21.3333px; text-align: left; vertical-align: baseline;">Immune System Part 2: Specific Defense <span style="color: #000000; font-family: Arial; font-size: 21.3333px; text-align: left; vertical-align: baseline;">[] <span style="color: #000000; font-family: Arial; font-size: 21.3333px; text-align: left; vertical-align: baseline;">Another immune system series (3 parts) <span style="color: #000000; font-family: Arial; font-size: 21.3333px; text-align: left; vertical-align: baseline;">[]

Using a computer and research materials research disorders of the immune response Outline the cause and effect to detail including the role of the humans immune response. This can be set out as a poster, information brochure or powerpoint presentation. It is also a useful tool, or idea as a SAC for the Self and Non Self topic. Useful websites include: [] [|http://www.healthinsite.gov.au] [] []
 * Learning Activity 3 **
 * Immune system disorders**
 * Autoimmunity
 * Hypersensitivity
 * Allergens and allergic responses