Infection and Response
Non-communicable- diseases that cannot be transferred from one person to another. Not
contagious. E.g. cancer
Communicable- diseases that can be transferred from one person to another. Contagious. E.g. HIV
A pathogen is a microorganism that causes infectious diseases. They depend on their host to provide
the conditions and nutrients they need in order to reproduce.
Viruses- e.g. measles
Bacteria- e.g. salmonella
Protists- e.g. malaria
Fungi- e.g. athlete’s foot
How are they spread-
Food and water
Vector (Insect bites)
Direct contact
Indirect contact
Mother to Baby
Body Fluids
Sharing personal items
Body Defences:
Skin- the dead cells do not let pathogens penetrate through
Nose- cilia hair stop it and mucus traps the pathogens
Trachea/Windpipe- cilia hair
Stomach- enzymes, acid
Symptom delay:
People with infections do not develop symptoms as soon as they are infected with a pathogen
1. Pathogen enter an organism
2. Pathogen reproduce rapidly (20 minutes) in ideal condition (incubation period)
3. Pathogen make harmful toxins, which build up. Moore bacteria=more toxin build up
4. Symptoms then develop (headache, fever
Cilia are tiny hair like structures
Your immune system recognises and destroys infection..
Role of White Blood Cells:
Ingesting
Producing antibodies
Producing antitoxins
Phagocytosis- It ingests and digests the pathogen, destroying it
Lymphocyte- antibodies/ antitoxins are made here
Non-communicable- diseases that cannot be transferred from one person to another. Not
contagious. E.g. cancer
Communicable- diseases that can be transferred from one person to another. Contagious. E.g. HIV
A pathogen is a microorganism that causes infectious diseases. They depend on their host to provide
the conditions and nutrients they need in order to reproduce.
Viruses- e.g. measles
Bacteria- e.g. salmonella
Protists- e.g. malaria
Fungi- e.g. athlete’s foot
How are they spread-
Food and water
Vector (Insect bites)
Direct contact
Indirect contact
Mother to Baby
Body Fluids
Sharing personal items
Body Defences:
Skin- the dead cells do not let pathogens penetrate through
Nose- cilia hair stop it and mucus traps the pathogens
Trachea/Windpipe- cilia hair
Stomach- enzymes, acid
Symptom delay:
People with infections do not develop symptoms as soon as they are infected with a pathogen
1. Pathogen enter an organism
2. Pathogen reproduce rapidly (20 minutes) in ideal condition (incubation period)
3. Pathogen make harmful toxins, which build up. Moore bacteria=more toxin build up
4. Symptoms then develop (headache, fever
Cilia are tiny hair like structures
Your immune system recognises and destroys infection..
Role of White Blood Cells:
Ingesting
Producing antibodies
Producing antitoxins
Phagocytosis- It ingests and digests the pathogen, destroying it
Lymphocyte- antibodies/ antitoxins are made here
