Chapter 1

Digestion

Pathogen
1. Disease causing microorganism
  1. Bacteria
  2. Virus
  3. Fungi
  4. Disease is recognisable symptoms
    1. Damage host tissues
    2. Produce toxins
2. Causes infection
3. To cause disease, it must: Gain entry to host, Colonise tissues of host, Resist defences of host, Cause damage to host tissues
Entry to body
1. Interfaces
  1. Excahnge surface/boundary, linking two systems
  2. Skin
    1. Effective barrier: forms thick, continous layer
    2. Cut or abrasion - easier entry
  3. Common entry for pathogenic microorganisms, due to some adaptations: thin, moist, sticky, large surface area, well supplied with blood vessels
2. Gas-exchange system
3. Digestive system
4. Adaptations: Thick mucous layer that covers exchange surfaces and forms a thick, sticky barrier, hard to penetrate - Production of enzymes, - production of stomach acid.
Chemical
1. Breaks down large, insoluble molecules, into smaller, soluble ones
2. Uses enzymes, called hydrolases
  1. Hydrolysis is the splitting up of molcules by the addition of water
3. Examples of hydrolases: Carbohydrases, lipases, proteases.
4. Assimilation - the incorporation of molecules into body tissues
5. Absorption - taking soluble molecules into the body
Physical
1. Break down of large pieces of food into smaller ones by the means of structures, such as teeth
2. Makes it possible to ingest food
3. Provides a large surface area for chemical digestion
4. Enter text here

Zusammenfassung der Ressource

	Erstellt von arsenaltwins vor fast 12 Jahre