Infection and Response essential knowledge quiz for revision

What is a pathogen?

A harmful microorganism that can cause disease

What are the 4 types of pathogen

Virus, bacteria, fungi, protozoa

How are pathogens spread (general ideas)

Air droplets, sexual intercourse, food containing pathogens which is eaten, in water contaminated by pathogens, by insects/animals

Examples of non specific defences from pathogens

Nose and ears, skin, trachea, stomach

How does the trachea defend the body from pathogens

Has mucus, traps pathogen, cilia moves mucus out of trachea

How do bacteria make us I’ll

Releases toxins, damage tissues , makes us feel unwell

How can bacteria be killed?

Antibiotics

Why can antibiotics not kill viruses

They live inside our cells, so drug cannot access them

How do viruses work

Live inside cells and reproduce, causing cell damage

Are viruses classed as cells

No

Why are viruses not classed as cells

Don’t have cell membrane, cytoplasm or nucleus

What are factors which make something living (MRSGREN)

Movement, respiration, sensitivity, growth, reproduction, excretion, nutrients

What happens if HIV is not treated

Can develop into AIDS

What does AIDS stand for

Acquired Immunodeficiency Syndrome

What happens to the immune system when someone has AIDS

Becomes so badly damaged and can no longer deal with other infections or cancers

How is Salmonella spread

Pathogens in food, contamination

What are symptoms of salmonella

Diarrhoea, sickness, abdominal pain

How can salmonella be prevented

Eating thoroughly cooked food, vaccinated chickens

What are treatments for salmonella

Antibiotics, IV

How is gonorrhoea spread

Sexually transmitted disease

What are symptoms of gonorrhoea

Coloured discharge, painful when urinating

How can gonorrhoea be prevented

Condoms

What is the treatment for gonorrhoea

Antibiotics

How is measles spread

Air droplets inhale from sneezes and coughs

What are symptoms of measles

Rash, fever

How can measles be prevented

Vaccination, isolation of infected people

How can measles be treated

Only symptoms can be treated; paracetamol

How is HIV spread

Sexual contact, sharing needles

What are syntone of HIV

Flu like symptoms, inability to fight off other infections

How can HIV be prevented

Condom during sex

How can HIV be treated

Antiretroviral drugs to stop virus replicating

How is TMV spread

Contact between plants, indirect contact from humans

What are symptoms of TMV

Mosaic pattern on leaves, stunted growth

How can TMV be prevented

Remove infected plants, wash gardening tools

How can TMV be treated

No treatment

What is the process of phagocytosis

White blood cells engulf, ingest and then digest the pathogens using enzymes

Describe how the immune system defends the body against disease (6 marker)

• Phagocytosis

• Microbe destroyed by powerful digestive enzymes in white blood cell

• WBC release antitoxins, bind to toxin, neutralise effect, now harmless

• WBC release antibodies which are complimentary to shape of antigens.

Which organelles to WBC have lots of

Mitochondria and ribosomes

What are antigens made of

Proteins

What do vaccines contain

Small quantities of dead or inactive forms of pathogens

How do vaccines work (3-4 mark question)

• When injected, stimulates WBC to produce antibodies

• Antibodies specific to pathogen so destroys them

• Person now immune to future infection, has memory cells

What does efficacy mean

Does the drug work

What is a placebo

Looks the same but doesn’t contain the drug

Describe the preclinical phase of drug development

• Drug tested on cells, tissues, small animals like mice

• Finds out if drug is toxic

Describe phase 1 clinical trial

• Drug tested on healthy volunteers, low dose

• Healthy people = easier to see side effects, checks whether drug is safe or has side effects

Describe phase 2 clinical trial

• Drug given to small number of patients with disease

• Allow scientists to monitor efficacy

Describe phase 3 clinical trial

• If drug success, given to larger group patients with disease

• Get correct dosage

• Look for rare side effects that affect small number of people

How many patients are given placebo in clinical trials

Half

When did Fleming discover penicillin

1928

What is a mutation

Change in the DNA sequence

What causes bacteria to become resistant to antibiotics

Bacteria mutating randomly

What does antibiotic resistant bacteria mean

Bacteria cannot be killed by antibiotics, they are resistant

How does antibiotic resistant bacteria develop

1. Some bacteria replicate

2. Non resistant bacteria die

3. Resistant bacteria reproduce

4. Genes mutate

Two ways to reduce antibiotic resistance

1. Patients should complete course of antibiotics

2. Should not prescribe antibiotics for viral infections

Digitalis: where from, treats what

Foxglove plants, heart condition

Aspirin: where from, treats what

Willow tree, painkiller

Morphine: where from, treats what

Poppies, painkiller

What are impacts of rose black spot

• slows growth of plants

• Less chlorophyll→less photosynthesis→less glucose→less respiration→less energy for growth

• Leaves can be yellow when chlorophyll broken down

Formula for calculating percentage increase/decrease

New value - original value X100

Original value

Which pathogen causes rose black spot

Fungi

How is rose black spot spread

Wind and water

What are symptoms of rose black spot

Black spots

How is rose black spot prevented

Isolation

How is rose black spot treated

Fungicides, removing/destroying affected leaves

Which pathogen causes malaria

Protist

How is malaria spread

Vectors- mosquitos

What are symptoms of malaria

Fever, chills, swearing, body shaking

How can malaria be prevented

Prevent mosquito breeding, nets, insect repellent, draining swamps they breed in

How is malaria treated

anti malarial drugs

What does the MMR vaccine protect against

Measles, mumps, rubella

What are monoclonal antibodies made from

Single clone of cells

How do monoclonal antibodies work

Specific to one antigen, able to target specific chemicals or cells in the body

Describe how monoclonal antibodies are produced (mice, 6 marker)

1. Mouse injected with antigen or protein

2. Lymphocytes produce antibodies. Extract lymphocyte that produces antibodies

3. Fast dividing tumour cell fuses with this, forming hybridoma cell

4. Single hybridoma cells cloned to produce many identical cells that produce same antibody

5. Large amount of antibody can be collected and purified, ready for use

Describe how pregnancy tests work

• hcG is a hormone found in pregnant women

• This binds to antibodies

• Mobile antibodies bind with anti hcG antibodies and dye shows in window if pregnant

What are symptoms of disease in plants

Discolouration of leaves, spots, presence of pests, chlorosis (yellow leaves)

Describe how ash dieback fungus and rise blast fungus affects plants

Ash dieback: malformed stems or leaves

Rise blast: decay

What do magnesium ions do for a plant

Make chlorophyll

What do nitrate ions do for a plant

Make amino acids to form proteins for growth

What are aphids

Small insects that can infect plants

How do aphids harm plants

Remove sugars from phloem, so not enough glucose to make proteins for growth