Unit 3 Biology: Infections & Response

Health definition

State of a persons physical and mental wellbeing

Communicable definition

An illness or disease caused by a pathogen that can be spread from one organism to another

Non communicable

An illness or disease caused by a persons lifestyle or genetics

Examples of communicable diseases

Cold & flu, HIV, Malaria, Salmonella, Measles

Examples of non communicable diseases

Cancer, heart disease, parkinsons

5 Ways that our bodies can defend themselves from microorganisms

White blood cells, skin, hair, stomach acid, mucus

One difference between a bacteria and animal cell

In a bacteria cell the DNA is stored in plasmids whereas with an animal cell DNA is stored in the nucleus

Why can’t antibiotics be used to treat HIV or measles?

HIV and measles are viral diseases and not bacterial

What type of drug can be used to treat HIV?

Antiretroviral drugs

Symptoms of gonorrhoea (BACTERIAL)

Symptoms: Pain when urinating, thick yellow or green discharge

Treatment for gonorrhoea (BACTERIAL)

Treatment: Antibiotic drugs e.g. penicillin

Prevention of gonorrhoea (BACTERIAL)

Prevention: Condom barrier method, abstinence

Symptoms of measles (VIRAL)

Symptoms: fever and a red skin rash

How does measles spread? (VIRAL)

Spread: Airborne, infected droplets in coughs & sneezes

Controlling measles (VIRAL)

Control: Vaccination (mmr), wash hands, keep distance, face masks

How is HIV spread? (VIRAL)

Spread: Infected body fluids (blood, saliva, sexual fluids), drug needles, sexual contact with no condom

What happens if HIV is not successfully controlled?

Explain: Virus attacks white blood cells, damages immune system

Effects of TMV Tobacco Mosaic Virus (VIRAL)

Effects: Discoloured leaves yellow or white, Chloroplasts are damaged, less photosynthesis = less growth

Controlling TMV

Control: Isolate/burn infected, wash hands when gardening

What is the pathogen causing salmonella & gonorrhoea?

Bacteria

What is the pathogen causing measles, HIV & TMV?

Viruses

How do viruses cause damage?

Viruses live and reproduce inside cells causing damage

How does bacteria cause damage?

Bacteria produces toxins that damage tissues and make us feel ill

What pathogen is malaria?

Protist

What pathogen is rose black spot?

Fungi

Symptoms of malaria

Symptoms: fever

What is a vector?

A vector is an animal that carries a disease but does not suffer from it

When somebody gets infected with malaria what happens?

The red blood cell becomes infected then bursts/ruptures this means that less oxygen is transported around the body.

How can we reduce the transmission of malaria?

Insect repellent, Covering body, Bed nets

How can we get rid of mosquitos?

Spray insecticides, drain breeding grounds, genetic engineering, planting eucalyptus trees

Symptoms of rose black spot

Symptoms: Purple or black spots appear on leaf, leaves often turn yellow and fall off

What happens when a plant develops rose black spot?

Chloroplasts are damaged, photosynthesis is reduced, less glucose is made, stunted growth

How is rose black spot spread?

Spread: Fungal spores spread by wind or water

How do we treat rose black spot?

Treatment: removing infected leaves & burning them, spray with a fungicide

How does stomach acid protect the body from disease?

The stronger the stomach acid (Highest is pH 1) the easier the pathogens can be killed

Explain how the respiratory system protects the body from pathogens

1-The respiratory system is lined with mucus.

2- This mucus helps to trap dust and pathogens

3- Cilia moves the mucus upwards to be swallowed.

4-This protects us because it stops pathogens building up in the respiratory system

How does the skin act as a defence against pathogens?

1- The skin is a waterproof barrier which is hard to penetrate

2- Glands in our skin secrete oil which kills pathogens