B5 Flashcards
What is a disease
An illness or disorder of the body or mind the leads to poor health
Defenition of bacteria and pathogens
Bacteria divide rapidly by splitting into two (binary fission). Produces toxins that affect your body and make you feel ill. Can directly damage your cells.
Vriuses take over your cells of your body. Live and reproduce inside the cells,damaging and destroying them.
How are pathogens spread person to person
By air- pathogens can be carried in the air and then breathed in as when you sneeze,cough or tslk you expel droplets.
By direct contact-touching contaminated surfaces, kissing, contact with bodily fluids, microorganisms from faeces, infected plant material left in field, sexually transmitted infections through direct sexual contact.
By water- drinking or coming into contact with dirty water. Fungal spores carried in splashes if water often spresd plant diseases.
Defeniton of health
Is a state of physical and mental wrll-being. Health is not just an absence of disease.
Difference between communicable and non-communicable disease
Communicable disease are caused by oathogens such as bacteria and viruses thst can be passed from one person to another
Non-communicable disease cannot be transmitted from ine person to another.
Factors that affect health
Diet- if you do not get enough to eat, right nutrients, you may suffer disease ranging from stravation to anaemia or rickets. Too much food or wrong food can lead to obesity, some cancers.
Stress- too much stress to an increased risk of developing a wide ranve of health problems, heart disease,cancers, mental health.
Life situations-gender,fanincial status,ethnic group
Prevention of disease transmittion
Hygiene- handwashing and disinfecting surfaces, coughing/sneezing into tissue,keeping raw meat away from uncooked meat
Isolating infected individuals- infectious disease such as ebola or cholera, person needs to be kept isolation as the fewer healthy people who come in contact with person,less likely it is that pathogens will be passed on.
Destroying or controlling vectros-if vectors destroyed, spread of disease can be prevented.
Vaccunation- Doctors introduce a small amount of harmless form of specific pathogen into your body. If you come in contact with live pathogen, you eill not become ill as your immune system will be prepared. Successful for proetcting large amount of people and animals against diseases.
Who did igna semmelweis do
-noticed that medical students went straight from dissecting a dead bodg to delivering a baby without washing hands
-he insisted medical students to wash their hands before deelivering babies which caused fewer mothers to die from fever
-resistance to his ideas meant that hand washing was not adopted quickly as lack of evidence about pathogens themselves.
What did louis pasteur do
-showed microorganisms caused disease. Germ theory that germs caused diseases
-developed vaccines against diseases such as anthrax and rabies
-developed ways to stain bacteria for viewing under microscopes
-first man to make a vaccine in lab
What did jospeh lister do
-used antispetics chemicals to destroy pathogens before they caused infection in operating theatres
-used antiseptics and disinfectants:wash hands, clean sheets,sterilise equipment
Viruses
Measles
Symptoms-fever and red skin rash
How is it spread- inhalations of droplets from coughs and sneezes
How is treated-no treatment but vaccination programme for young children
HIV
Symptoms-mid,flu-like symptoms
How does HIV cuase damage- attacks immune system until so badly damaged that can no longer deal with infections and cancers which leads to AIDS
How is it spread-direct sexual contact and and exchange of body fluids such as blood when drug users share needles. Passed from mother to child in breast milk
Prevention-use condomds, not sharing needles,screening blood when used in tranfussions,bottle-feeding
Tobacco masoaic virus
Which plants affected-tomatoes and tobacco plants
Symptoms-discolouration of leaves as destroys cells, affacted leaf cannot photosynthesise resulting in reduction of yield
How is it spread-contact between diseased plants and healthy plants and insects act as vectors
Prevention- pest control,TMV resistant strains
Bacteria
Salmonella
What are they and where found-bacteria that live in guts of many animals and found in raw meat,poultry,eggs
Symptoms-fever,stomach cramp, diarrohea,vomitting
Prevention-keep raw chicken away from food that is uncooked,aboid washing it, wash hands and surfaces when handling it
Gonorrhea
Symptoms- thick yellow or green discharge from vagina or penis,pain when urinating
How it spread- secually transmitted disease spread through unprotected sex
Prevention-contraeception and antibiotics
Fungal and protists disease
Rose black spot
Sympyoms£purple and black on leaves of rose plants, reduces the area of leaf to photosynthesise,leaves turn yellow and drop
Spread-the spores of fungus are spread in water by wind
Prevention- removing and burning affected leaves, using fungicides (stem chemicals)
Malaria
They live and feed libing organisms
Symptoms- fevers and shaking
Spread-female mosquitoes in which protists reproduce sexually. When protists punctures skin to feed on blood, protists enters the human bloodstream and travel in cirulatory system which affect liver and damage red blood cells
Prevention- using insecticide coated insects nets when sleeping, removing stagant water to prevent vectors from breeding, killing mosquitoes
Huma defence system
Skin- acts as physical barrier that prevent pathogens entering body
- produces antimicrobial secretions that kill pathogens
-good microorganisms (skin flora) compete with bad microorganisms for space and nutrients
Nose- full of hair and mucus. Hairs and mucus trap particlss in air thst may contain pathogens that prevent from entering lungs
Trachea and bronchi- secret mucus in order to trap pathogens
-cilia beat to waft mucus upwards so it can be swallowed
Stomach-produces hydrochloric acid that kills any pathogens in mucus, or food and drink
Protection from pathogens in body
Phagocytes (engulf and consume pathogens)-white blood cells ingest oathogen,digesting and destroying them
Lymphocytes (antibodies)- each pathogen has an anitgen on surface so a antibody can bind to it. Once antibodies begin to bind to pathogen, pathogens clump together resulting in it being easier for white blood cells to find them
If you become infected again, the antibodies will be produced at a faster rate. The individual will not feel the symptoms of the illness so are immune to them.
Lymphocytes (antitoxins)-they neutralise the toxins released by pathogen binding to them
