Diseases

Year 8 Science

What is Disease?

Infectious or non-infectious?

• Infectious (or contagious or communicable) diseases are caused by pathogens.

• Non-infectious (non-contagious or non-communicable) diseases have various causes:

poor nutritionsmokingpollution – air, water, soilgenetics – inherited diseasescancer (uncontrolled cell growth)auto-immune responses

Nutritional Diseases

• Scurvy – lack of Vitamin C• Goitre (enlarged thyroid) is

caused by a lack of iodine.• Kwashiorkor (protein

deficiency)

Nutritional Diseases

• Beriberi (lack of thiamine)• Pellagra (lack of niacin)

Nutritional DiseasesObesity causes • heart disease• diabetes II• high blood pressure• Cholesterol• Strokes• Gallstones• Gout• Osteoarthritis• pregnancy and bladder

problems• Depression • Some cancers.

Genetic Diseases

• Affect the chromosomes• Down’s Syndrome• Progeria (rapid ageing)

Cancers

• Melanoma (skin cancer)• Ovarian & Breast• Testicular & Prostate • Throat and lung • Leukemia (blood)

Auto-Immune Diseases

• Lupus• Coeliac and Crohn’s

disease• Eczema

Pathogens

Pathogens can be microscopic or macroscopic.They include:• Prions• Viruses• Bacteria• Fungi• Protozoans• Parasites (internal and external)

Prions

• Mad Cow Disease (Bovine Spongiform Encephalitis or BSE)

• Creutzfeldt Jakob disease

Viruses

• Smallpox• Influenza• Mumps• Measles• Chicken Pox• Ebola • Rubella• Herpes

Bacteria

• Diptheria• Tuberculosis• Tetanus• Typhoid• Pneumonia• Salmonella• Staphylococcus

Fungi

• Athlete’s foot (Tinea) • Ringworm• Aspergillosis

Internal parasites – Protozoans and worms

• Malaria (caused by Plasmodium)

• Sleeping Sickness (caused by Trypanosomes)

• Hookworm• Amoebic Dysentry

External Parasites

• Scabies• Lice• Leeches• Ticks

Vectors

• Vectors are organisms that can transmit disease by acting as a host for pathogens

• Flies can transmit bacteria causing food poisoning.

• Rats and mice carry fleas, which can transmit disease.

• Mosquitoes can carry malaria, dengue fever and yellow fever.

Your task:Research: Choose a disease that you may be interested in and answer the following questions in a report about that disease:

1. Is it infectious/contagious?2. Where does it commonly occur?3. What are the symptoms of this disease?4. What causes the disease?5. Is it spread by vectors?6. How is the disease treated?7. How can the disease be prevented?

Presentation

You can choose one of the following methods to present your work:

• Prepare a pamphlet or brochure that explains the disease to patients and sufferers.

• Produce a slideshow or Voicethread about the disease (including CC images)

• Film a role play about a patient and doctor diagnosing and treating the disease.