1.1 (P2) Defence Against Disease Flashcards Preview

AQA GCSE - Biology > 1.1 (P2) Defence Against Disease > Flashcards

Flashcards in 1.1 (P2) Defence Against Disease Deck (36)
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1

What is a pathogen

Microorganisms that cause infectious diseases

2

What is a virus

A DEAD pathogen
It cannot survive long unless inside a host cell

3

How do viruses attack you

They take over the nucleus in your cells and make copies of themselves then burst out and infect other cells

They reproduce rapidly and damage the cells

4

What is a bacteria

An ALIVE pathogen

5

How do bacteria attack you

They release toxins that make you feel ill

6

Name three general defences

Natural barriers
Non-specific white blood cells
Specific white blood cells

7

Name 2 Non-Specific white blood cells

Macrophages
Helper cells

8

Name natural barriers you body has

Saliva
Mucus
Ciliated epithelial cells
Ear wax
Skin
Tears
Eyelashes

9

Name the specific white blood cells

B-cells
T-cells
Phagocytes

10

What do phagocytes do

The engulf pathogens and hold up to 10,000 before dying

11

Where are B-cells and T-cells found

In the lymph glands

12

What do B-cells target?

A virus

13

What do T-cells target?

Bacteria

14

What do B-cells do?

They produce antibodies
The tiny proteins are sent to the infection via the blood stream
They attach themselves to the

15

What do T-cells do?

They multiply and go out if the gland to the infection themselves
They release antitoxins which only targets the infected cell

16

What can happen to T-cells?

They remain in the body in small quantities
They are called memory cells

17

What are memory cells vital for?

Immunity

18

Who is Ignaz Semmelweis?

A Hungarian physician

He found the link between microbes and infection

He saw doctors didn't wash their hands between an autopsy and delivering a baby

He told them to wash their hands to prevent the spread of pathogens

19

What do painkillers do?

They relive the pain and symptoms

They don't kill the pathogen

20

What are antibiotics?

They cure bacterial infections

They are natural - you can't make them

21

Do antibiotics work on viruses? Why?

No

They reproduce inside host cells which makes it hard to target without killing the other cells also

22

What is the first antibiotic?
Who discovered it?

Penicillin
Alexander Flemming

23

What is the term for a change in DNA causing variation?

Mutation

24

What causes mutation?

Overuse
Inappropriate use

25

How does antibiotic resistance occur?

Natural selection

26

How does a resistant strain form?

Antibiotics kill individual pathogens of the non-resistant strain

However, some mutate and survive and reproduce

The population of the resistant strain increases

27

Name a resistant strain of bacteria

MRSA

29

What aren't antibiotics used for and why?

Mild throat infections
So the rate of resistant strains slows down

30

What is a vaccine?

A small dead version of the virus

31

What vaccine is given to children?

MMR