DISEASES & PATHOGEN

Diseases

A disease can modify or affect chemical reactions in the body and set it to disequilibrium. 

Non-communicable: self-inflicted or created by environmental conditions, such as dietary deficiency diseases or cancers

E.g:

1. Scurvy
2. Rickets
3. Obesity
4. Anorexia
5. Coronary heart diseases

Communicable: Due to agents such as viruses or bacteria, which are passed between organisms

E.g:

1. Cough
2. Flu
3. Malaria
4. Athlete's Foot

Pathogen 

cause the disruption of the equilibrium of the body & the immune system helps to restore & maintain the equilibrium

** Not all bacteria are pathogen! (yaklut) But pathogen can be bacteria** 

• Organisms that cause disease and lives in or on another organism.
• When they infect an organism, they

1. Destroy cells
2. Produce toxins
3. Interfere with normal functions in organism
4. Invokes immune response that, if excessive, harms the organism.

• To infect an organism, the organism must 

1. able to survive the transmission from one host to another. 
2. able to enter the host. 
3. virulent – the ability to overcome body defenses (through its own replication) & only need to be initially present in small numbers. 

Different classes of pathogens:

• Bacteria 
• Viruses 
• Protozoa 
• Parasites
• Fungi 

Further Readings:

Botox - http://dermatology.about.com/od/cosmeticprocedure/a/botox.htm

HIV/ AIDS - http://www.google.com.sg/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&sqi=2&ved=0CEQQFjAC&url=http%3A%2F%2Fen.wikipedia.org%2Fwiki%2FHIV%2FAIDS&ei=lnxSUNrSJYzorQeQ3YG4Bg&usg=AFQjCNF0DBD0fizNfrRaYD9L4NMDXgr8wg&sig2=udJp1yPcZJ9U5ZR0EyfePA

CLARIFYING QNS:)

1) Does diffusion occur instantly?

Diffusion - matter are made up of particles that are always moving. Thus, answer is no.

2) Difference between ingestion & digestion?

Ingestion - process of "eating" of taking in nutrients.
Digestion - mechanical, chemical

*similarity: occur at the same time.

3) What does it mean for intestine to be convoluted

** increase surface area to volume ratio

4) What is the difference between bile & bile salts?

In our level, we can use both. Bile salts is in bile:)

5) Function of semi-lunar valve and tricuspid valve?

Tricuspid Valve (Right Hand Side) --> preventing the back-flow of blood from the right ventricle to the right atrium of the heart

6) Heavy smoking affect heart?

nicotine--> hardening of vessels
cholestrol gets trap in the vessels.