bio chap 8 - infectious diseases in humans

Question 1

What is a disease?

Answer 1

A condition that forces the body to function less effectively

Question 2

What is a sign of a disease? Name examples

Answer 2

Observed or measured
Rashes, fever, vomiting coughing

Question 3

What is a symptom of a disease?

Answer 3

Described or felt by the patient
Headaches, fatigue, nausea

Question 4

What are the characteristics of an infectious disease? Name some examples

Answer 4

Spread from one person to another
Caused by pathogens
Influenza, HIV, pneumococcal disease

Question 5

What are the characteristics of non-infectious diseases? Name some examples

Answer 5

Cannot be spread from one person to another
Not caused by pathogens but rather inherited or caused by factors such as air pollution malnutrition or lifestyle choices
Sickle cell anaemia, type 2 diabetes, liver cirrhosis and coronary heart disease

Question 6

How are infectious diseases spread by droplets in the air?

Answer 6

When a person coughs or sneezes, numerous tiny droplets that may contain pathogens are expelled

Anyone within a close range may breathe in these droplets and maybe infected

Question 7

Why is wearing a mask advised when there is a disease outbreak?

Answer 7

Reduces likelihood and severity of transmission and amount of pathogens released by a person into the air

Question 8

How are infectious diseases spread by direct contact?

Answer 8

Exchanging bodily fluids during sexual intercourse

Blood from an infected person comes into contact with mucous membrane and the bloodstream through a break in the skin

Question 9

Give an example of infectious diseases spread by direct contact

Answer 9

STIs such as HIV hepatitis b and syphilis can be transmitted from mother to baby while breast feeding

Question 10

How are infectious diseases spread by contamination of food and water?

Answer 10

Food and water can be contaminated by pathogens when are not properly stored or handled

Question 11

What are the methods to prevent food and water bourne diseases?

Answer 11

Practising hygienic food preparation and storage, personal hygiene, maintaining a clean water supply and ensuring proper sewage treatment

Question 12

What are the characteristics of the influenza virus?

Answer 12

Caused by the influenza virus
Attacks respiratory system
Recovery within 2 weeks
May lead to complications such as pneumonia

Question 13

How is the influenza virus transmitted?

Answer 13

Through air droplets
When a person touches a surface contaminated with the virus, then touches their mouth, nose or eyes

Question 14

what are the symptoms of influenza

Answer 14

high fever, headache, stuffy nose, cough, sore throat, muscle aches

Question 15

what are the 6 ways to reduce transmission of the influenza virus?

Answer 15

annual influenza vaccination

avoid coming into contact with people who have the flu and vice versa

if you are sick, cover your mouth and nose with tissue when you cough or sneeze and dispose it properly… or wear a face mask

wash your hands with soap and water or rub with disinfectant or hand sanitisers

avoid touching eyes nose and mouth

take antiviral drugs prescribed by a doctor to treat the illness

Question 16

what are the characteristics of pneumococcal disease?

Answer 16

caused by pneumococcus bacteria

attacks different parts of the body
leads to serious infections of the lungs, blood and spinal cord

Question 17

how is pneumococcal disease transmitted?

Answer 17

by respiratory droplets?

Question 18

what are the signs and symptoms of pneumococcal disease?

Answer 18

fever cough headache chest pain vomiting rapid breathing

Question 19

what are the 3 methods to reduce transmission of pneumococcus bacteria?

Answer 19

pneumococcal vaccination
daily preventive actions similar to influenza
- avoid cmg into close contact w ppl who have the disease
- if you are sick cover your mouth and nose with tissue or wear a mask and dispose it properly
- wash your hands with soap and water/ rub w disinfectant or hand sanitisers
- avoid touching eyes, nose and mouth

take antibiotics as prescribed by the doctor to treat the disease

Question 20

what are vaccines?

Answer 20

contains an agent that resembles a pathogen and prevents infectious diseases by stimulating WBC to quickly produce antibodies when the pathogen invades

taken orally or through an injection

Question 21

how do vaccines work?

Answer 21

antigens trigger the production of antibodies
when an antigen enters the body it stimulates the WBC to quickly destroy them

WBC binds to agent
WBC is stimulated to divide
WBC produce antibodies
antibodies destroy the agent in the vaccine
some of these WBC will remain in the bloodstream
- in the future if live pathogens enter the bloodstream, WBC will recognise them and quickly produced antibodies to destroy the pathogens bfr infecting our cells

Question 22

what are antibiotics?

Answer 22

drugs to treat bacterial infections made by microorganisms and are used to kill/inhibit bacterial growth

Question 23

how do antibodies work?

Answer 23

weakens the bacterial cell wall allowing water to enter the bacterial cell by osmosis, causing it to swell and burst

inhibits some enzymes which inhibits bacterial growth

prevents ribosomes from making proteins and enzymes, killing bacteria

breaking up bacterial cell membranes

Question 24

why are antibiotics ineffective against viruses

Answer 24

viruses do not have cell walls, cell membranes or ribosomes

Question 25

what are superbugs?

Answer 25

bacteria resistant to medicines such as antibiotics

Question 26

what are the possible outcomes of taking a course of antibiotics

Answer 26

in a population of bacterial cells, some are more sensitive to the antibiotics while others are less sensitive

when antibiotic is taken, the bacterial cells that are more sensitive are killed
the bacterial cells that are less sensitive are not easily killed and may survive

if the prescribed course of antibiotics id not completed - less sensitive bacterial cells that survive will multiply and increase

if the prescribed course of antibiotics are completed
there is a higher chance that all bacterial cells are killed

Question 27

how does antibiotic resistance occur?

Answer 27

overtime the subsequent generations of bacterial cells will be less sensitive to the antibiotics and may eventually become resistant

the antibiotic will not be able to kill the the resistant bacterial cells

other types of antibiotics will be required to treat the bacterial infection

Question 28

what are the 3 ways to reduce antibiotic resistance?

Answer 28

not misusing or overusing antibiotics

completing the full course of antibiotics prescribed by doctors so that all bacteria are killed

using antibiotics only when necessary