B4 health matters Flashcards
Good health
Having a complete physical and mental health
Bad health caused by
Disease
Diet
Stress
Life situations
Communicable
Spread easily
Non communicable
Can’t be spread
Bad diets and their effects
High fat/sugar- high blood pressure, depression,heart problems, diabetes
Low calcium- osteoporosis
Red meat/ processes meat- bowel cancer
Risk factors
Increase the chance of having a disease
Eg. Lifestyle, diet, exercise, workplace, relationship
Non communicable disease factors
Cardio- diet,obesity,age,genetics,exercise
Lung- smoking, cleanness of environment
Liver- alcohol,diet,obesity,genetics,drugs,viral infection
Type 2 diabetes- genetics, diet,obesity,exercise
Human and financial costs of smoking
Health problems to you or child, death
Expensive,loss of income,small workforce
Financial burden of healthcare costs on local, national and global economies
Pathogens
Microorganism that cause infectious diseases. They depend on their hosts to provide the conditions and nutrients they need to grow and reproduce.
Pathogens can be
Viruses
Bacteria
Protist
Fungi
How are pathogens spread?
Contaminated food and water pass through the mouth
Microorganisms in the air enter the nose
Microorganisms enter through the skin when skin is cut, bitten by insects or infected needles are used
Sexually transmitted diseases can be caught through the contact with infected reproductive organs
Bacteria and viruses
B- produce toxins that damage tissues and make us feel ill
V- live and reproduce inside cells, damaging them
Ebola haemorrhagic fever (EHF)
Symptoms-fever,headache,diarrhoea,nausea and rashes
Prevention- reduce contact with infected animals, wear protective clothing, wash hand frequently, isolation of infected people and safe burials of the dead, travel restrictions
Bacteria
Salmonella
Gonorrhoea (STD)
B symptoms
S- fever, vomiting, abdominal cramps, diarrhoea
G- thick yellow/ green discharge from vagina/penis pain when urinating
B transmission/ spread
S- ingesting contaminated food, preparing food in unhygienic conditions
G- sexual activity
B control measures & treatment
S- chicken gets vaccinated, prepare food in hygienic conditions
G- condom, antibiotics
Viruses
Measles
HIV
TMV (tobacco mosaic virus)
V Symptoms
M- fever, red rash
HIV- flu like symptoms
TMV- leaves discoloured mosaic pattern, reduce photosynthesis
V transmission/ spread
M- droplet infection
HIV- direct contact
TMV- enters plant via wounds
V control measures and treatment
M- vaccinations (MMR vaccine)
HIV- antiretroviral drugs,condoms,no needle sharing
TMV- removal of infected plant material, controlling pests, sterilising tools, washing hands
Fungal
Rose black spot
F symptoms
Black spots on leaves and stem
Leaves fall off prematurely
Can be purple
Spreads rapidly
F Transmission/spread
Water Wind Optimum temp 24 Spores realised in warm wet conditions 7 hours to germinate Symptoms show after 3-10 days Spores produce every 3 weeks
F control measures & treatment
Burn leaves Compost (especially mulch) Fungicide Pruning(fertilise afterwards) Sterilise tools
Protist
Malaria
P symptoms
Nausea/vomiting Fevers Kidney failure Mental confusion Headaches Diarrhoea Cough Muscle pains Seizures
P transmission/spread
Female mosquitoes
Protist enters from feeding mosquito
Travels to liver to reproduce
Leaves liver and reproduces in red blood cells, feeding on haemoglobin
Protist in blood passed to other feeding mosquitos
P control measures & treatment
Mosquito nets Vaccinations Education IV drugs Antimalarial drugs
How body defends itself
Skin is a barrier and produces antimicrobial secretions via gland in the skin
The nose traps particles that may contain pathogens
Trachea and bronchi secrete mucus taps pathogens
Stomach produces HCl killing pathogens
Platelets clot at wounds to seal it (fibrin)
White blood cells
They attack invading pathogens. If a pathogen enters the body, white blood cells defend it by:
Ingesting pathogens (phagocytosis)
Producing antibodies
Producing antitoxins
Phagocytes
Can leave the body by squeezing through capillaries to enter tissues that are being attacked. They move towards pathogens or toxins and ingest them. (PHAGOCYTOSIS)
2 types of white blood cells
Phagocyte and lymphocytes
Lymphocytes
Produce antitoxins to neutralise toxins made by the pathogen. Antitoxins combine with the toxin to make a safe chemical. Antitoxins are specific to a particular toxin.
Antibodies
Cause cell lysis (the pathogens burst)
Bind the pathogens and destroy them
Cover the pathogens, sticking them together. Phagocytes then ingest them
Immunity
If the same type of pathogen enters the body again, lymphocyte cells recognise it and immediately make lots of antibodies.
A drug
Is any chemical that alters how the body works. They just relieve the symptoms caused by infection.
Antibotics
Work by interfering with the pathogen’s metabolism. Only kill bacterial pathogens.
Painkillers are based on 2 natural drugs
Aspirin from willow bark
Opiates from poppies
Antrival drugs
Treat viral infections.
Specific to a particular virus
Slow down viral development
It is difficult to develop drugs which kill viruses without damaging the body’s tissues
vaccination
Introduces a small quantity of an inactive or dead form of a pathogen into the body to protect us from disease
Why do we feel ill
Pathogens release toxins
How are vaccines given
Injection, orally, nasal sprays
How do vaccines work
Lymphocytes detect antigens on the dead/inactive pathogen; they produce a specific antibody for these antigens
Antibodies lock onto antigens
Lymphocytes remember the shape of the antigen
When there is a real infection, lymphocytes instantly remember pathogen
Antibodies lock onto pathogen and kill them before they have a chance to make you feel ill
Why is there new vaccinations every year
As some viruses frequently mutate into new strains. Lymphocytes don’t recognise them.
Boosters are given to increase the antibodies again for lifelong protection
New drugs are tested and trial led each year before being prescribed to ensure they are
Effective- able to prevent or cure a disease, or make you feel better
Safe- not too toxic or without any undesirable side effects
Stable- it must be possible to store for a period of time
Stages of drug development
Preclinical testing in laboratories (using cells,tissues and live animals) to find out side effects and efficacy
Clinical trial, which use healthy volunteers and other patients. Once deemed safe with low doses further trials are performed
Developing new drugs
Discovery (2-10 years)
Preclinical: laboratory and animal tests
Phase 1: 20-80 healthy volunteers to determine safety and dosage
Phase 2: 100-300 volunteers to look for efficacy and side effects
Phase 3: 1000-5000 volunteers to monitor adverse reactions to long term
MHRA review approval
Additional post-market testing
Trial results are peer reviewed by medical professionals and only then are they published
Clinical trials involve some risk because unexpected side effects can occur
Double blind trials
Patients randomly allocated I groups so doctors and patients don’t know if they are taking the drug or the placebo until trial is complete
Monoclonal antibodies
Come from cells that are clones from one cell. They can be produced and used over a long period of time.
Uses of monoclonal antibodies
For diagnosis- in pregnancy tests.mABs are used to measure the level of hormones and the other chemicals in blood, or to detect pathogens.
In research- they can be used to locate or identify specific molecules in a cell or tissue by binding them to fluorescent dye
To treat some diseases- eg. Cancer mABs bound to radioactive substance, a toxic drug or a chemical which stops cells growing and dividing.
Making monoclonal antibodies
Mouse injected with specific antigen to stimulate lymphocytes to make antibodies
Extracted lymphocytes combined with tumour cell
Detergent is used to break down cell membranes so they fuse together
Makes a hybridoma cell, which can divide and make antibodies
Single hybridoma cells are cloned to produce many identical cells that all produce same antibody. These are mABs
Large amount of mABs are collected and purified.
mABs side effects
Chills or fever Itchy rashes Nausea Breathlessness or wheezing Headaches Changes in blood pressure
Draw backs of monoclonal antibodies
Immune system rejects them as produced in mice
Creates more side effects than expected
Advantage of mABs
Helps treatment of cancer
Healthy body cells are unaffected
Target cancerous cells specifically
Plant diseases are important because
Plants are producers in food chains
They destroy crops and are hard to control
Aphids (greenfly)
Destructive small insects that reproduce quickly. Symptoms: Decreased growth rate Mottled or yellow leaves Wilting Low yields Death
Are a disease vector
Pierce phloem tube using specially adapted mouthparts. Feed on sap, lowering tutor pressure to cause wilting. Viruses are transferred to the phloem by salvia during feeding
Nitrate
Make amino acids= protein synthesis
Deficiency= stunted growth
Magnesium
Needed to make chlorophyll
Deficiency= chlorosis (yellow leaves)
Treating mineral deficiencies
Identified by chemical tests and the deficient mineral can be added to the soil. Sometimes it is more convenient to add a general-purpose fertiliser
Plant diseases can be indicated by:
Stunted growth Spots on leaves Areas of decay (rot) Growths Malformed stems or leaves Discolouration The presence of pests
Identification of diseases can be made by:
Reference to a gardening manual or website
Taking infected plants to a laboratory to identify the pathogen
Use testing kits
Physical plant defences
Layers of dead cells around stem prevent pests from entering
Tough waxy leaf cuticles that prevent pathogens entering epidermis
Cellulose cell walls which prevent pathogens from entering cells
Mechanical defences
Thorns and hairs- thorns impale insects, hairs prevent larvae reaching epidermis
Leaves droop/curl at touch- cells collapse
Mimicry-trick animals into not feeding/ laying eggs
Chemical defences
Production of antibacterial chemicals- increase when attacked by herbivores or pathogen
Production of poisons- taste bad to herbivores, can be useful to humans
