B1

HEALTH AND FITNESS

• HEALTHY - BEING FREE OF ANY INFECTIONS OR DISEASES
• FIT - MEASURE OF HOW WELL ONE CAN PERFORM PHYSICAL TASKS - MEASURED BY STRENGTH, SPEED, AGILITY, FLEXIBILITY AND STAMINA
• CARDIOVASCULAR EFFICIENCY - ABILITY OF THE HEART TO SUPPLY THE MUSCLES WITH OXYGEN

BLOOD PRESSURE

• BLOOD PRESSURE - MEASURE OF THE PRESSURE THAT ONES BLOOD IS PUMPED AROUND THE BODY UNDER, ICREASED BY CONTRACTIONS OF THE HEART - MEASURED IN MM OF MERCURY (mmHg)
• SYSTOLIC PRESSURE - PRESSURE OF BLOOD WHEN HEART CONTRACTS - TIME WHEN BLOOD PRESSURE IS AT IT'S HIGHEST (SHOULD NOT BE OVER 135)
• DIASTOLIC PRESSURE - PRESSURE OF BLOOD WHEN HEART RELAXES - TIME WHEN BLOOD PRESSURE IS AT ITS LOWEST (SHOULD NOT BE OVER 85)
• IDEAL BLOOD PRESSURE - 120(s)/80(d)

HIGH BLOOD PRESSURE

• FACTORS THAT INCREASE BLOOD PRESSURE - SMOKING, BEING OVERWEIGHT, DRINKING, STRESS
• COULD CAUSE BLOOD VESSELS TO BURST, LEADING TO STROKES, BRAIN DAMAGE, KIDNEY DAMAGE.
• CAN BE DECREASED BY CHANGES IN DIET, MORE REGULAR EXERCISE AND, IN EXTREME CASES, MEDICATION.

SMOKING AND HIGH BLOOD PRESSURE

• CIGARETTE SMOKE CONTAINS CHEMICALS WHICH INCREASE BLOOD PRESSURE
• CARBON MONOXIDE - COMBINES WITH HAEMOGLOBIN IN RED BLOOD CELLS, REDUCING AMOUNT OF OXYGEN THEY CAN CARRY. HEART RATE HAS TO INCREASE TO MAKE UP FOR THIS, MEAING THAT IT CONTRACTS MORE FREQUENTLY, INCREASING BLOOD PRESSURE
• NICOTINE - INCREASES HEART RATE, CAUSING MORE FREQUENT CONTRACTION, INCREASE BLOOD PRESSURE

LOW BLOOD PRESSURE

• CAUSES POOR CIRCULATION - TISSUES DON'T GET ENOUGH FOOD AND OXYGEN
• BRAIN DEFIICIENT IN FOOD AND OXYGEN - CAUSES DIZZINESS AND FAINTING

HEART DISEASE - ANY DISEASE THAT EFFECTS THE HEART

FACTORS WHICH INCREASE RISK

• DIET HGH IN SATURATED FATS - CAUSES HIGH LEVEL OF CHOLESTOROL (FATTY SUBSTANCE) IN BLOOD, WHICH BUILD UP IN ARTERIES AND FORM PLAQUES ON THE ARTERY WALL, NARROWING THEM AND RESTRICTING BLOOD FLOW TO THE HEART (CAN LEAD TO HEART ATTACKS)
• DIET HIGH IN SALT - CAUSES HIGH BLOOD PRESSURE WHICH INCRESES RISK OF DAMAGE IN ARTERIES, ENCOURAGING BUILD UP OF PLAQUES

NARROW ARTERIES

• HEART MUSCLE IS SUPPLIED WITH BLOOD BY CORONARY ARTERIES WHICH, IF NARROWED, CAUSE RESTRICTED BLOOD FLOW TO THE HEART, MEANING THAT THE HEART RECIEVES LESS OXYGEN
• IF A THROMBOSIS (BLOOD CLOT WHICH ALSO RESTRICT BLOOD FLOW) OCCURS IN AN ALREADY NARROWED ARTERY, IT CAN BLOCK BLOOD FLOW TO HEART COMPLETELY, MEANING THAT AN AREA OF THE HEART WILL BE CUT OFF FROM ITS OXYGEN SUPPLY
• THIS CAUSES A HEART ATTACK. 

BALANCED DIET

• CARBOHYDRATES - PROVIDE ENERGY
• FATS - PROVIDE ENERGY, ACT AS AN ENERGY STORE AND PROVIDE INSULATION
• PROTEINS - GROWTH AND REPAIR OF TISSUE, PROVIDE ENERGY IN EMERGENCIES
• VITIMINS AND MINERALS - VARIOUS FUNCTIONS ACCORDING TO TYPE OF VITAMIN/MINERAL
• WATER - PREVENT DEHYDRATION

CONTENTS AND STORAGE

• CARBOHYDRATES - MADE UP OF SIMPLE SUGARS LIKE GLUCOSE. STORED IN LIVER AS GLYCOGEN OR CONVERTED TO FATS
• FATS - MADE UP OF FATTY ACIDS AND GLYCEROL. CAN BE STORED UNDER SKIN AND AROUND ORGANS AS ADIPOSE TISSUE
• PROTIENS - MADE UP OF AMINO ACIDS. NOT STORED - ESSENTIAL AMINO ACIDS (NOT MADE BY BODY) COME FROM ANIMAL PRODUCTS (FIRST CLASS PROTIENS). PLANT PRODUCTS ARE SECOND CLASS PROTIENS

ENERGY AND NUTRIENT NEEDS - VARIATION

• AGE - CHILDREN NEED MORE PROTIEN FOR GROWTH. OLDER PEOPLE NEED MORE CALCIUM FOR BONE STRENGTH
• GENDER - FEMALES NEED MORE IRON TO REPLACE LOSS FROM MENSTRUAL BLOOD
• PHYSICAL ACTIVITY - ACTIVE PEOPLE NEED MORE PROTIEN FOR MUSCLE DEVELOPMENT AND MORE CARBOHYDRATES FOR ENERGY

DIFFERENT DIETS

• RELIGIOUS REASONS - ONES RELIGION MAY NOT ALLOW CONSUMPTION OF SOME FOODS 
• PERSONAL REASONS - VEGETARIANS AND VEGANS
• MEDICAL REASONS - INTOLLERENCES AND ALLERGIES
• EAR - ESTIMATED AVERAGE DAILY AMOUNT OF PROTIEN REQUIRED = 0.6 X BODY MASS (KG)
• BMI - BODY MASS INDEX = BODY MASS IN KG / (HEIGHT X HEIGHT) IN M

KWASHIORKOR - TOO LITTLE PROTEIN

• REASONS FOR PROTEIN LOW DIET IN DEVELOPING COUNTRIES -
• OVER POPULATION LEADS TO GREATER DEMAND IN PROTIEN RICH FOODS - NOT ENOUGH TO GO ROUND
• TOO LITTLE MONEY - NOT ABLE TO AFFORD AGRICULTURE ADVANCED ENOUGH TO FARM ENOUGH FOODS RICH IN PROTEIN

EATING DISORDERS - VARIOUS NUTRIENT DEFICIENCIES

• ANOREXIA NERVOSA - SELF STARVATION
• BULIMIA NERVOSIA - BOUTS OF BINGE EATING FOLLOWED BY SELF INDUCED VOMITING
• RESULT IN POOR DIET, LEADING TO HEART FAILURE, KIDNEY FAILURE, HEART ATTACKS, LOW BLOOD PRESSURE, MINERAL DEFICIENCIES

BMI

< 18.5 - UNDERWEIGHT                      > 25 - OVERWEIGHT                        >30 - OBESE

INFECTIOUS DISEASES

PATHOGENS - MICROORGANISMS THAT CAUSE DISEASE. TYPES: FUNGI, BACTERIA, VIRUSES, PROTOZOA

MALARIA

• CAUSED BY PROTOZOAN - CARRIED BY MOSQUITOES (INSECT WHICH FEEDS OFF BLOOD OF ANIMALS)
• PROTOZOAN IS A PARASITE (ORGANISM THAT LIVES OFF ANOTHER ORGANISM CALLED A HOST AND OFTEN CAUSES IT HARM)
• MOSQUITOS ARE VECTORS - CARRY DISEASE WITHOUT GETTING IT. THEY PICK UP MALARIAL PARASITE WHEN THEY FEED ON AN INFECTED ANIMAL. WHEN MOSQITO FEEDS ON ANOTHER ANIMAL, IT INFECTS IT BY INSERTING PARASITE INTO ANIMALS BLOOD VESSELS
• PREVENTION - AREA OF WATER WHERE MOSQUITOS LAY EGGS CAN BE DRAINED OR SPRAYED WITH INSECTICIDES
• FISH CAN BE INTRODUCED INTO WATER TO EAT MOSQUITO LARVAE
• PEOPLE CAN BE PROTECTED FROM MOSQUITOES FEEDING ON THEIR BLOOD - MOSQUITO NETS AND INSECTICIDES.

IMMUNE SYSTEM

• IMMUNE SYSTEMS JOB IS TO DESTROY PATHOGENS WHICH, IF LEFT TO, WOULD REPRODUCE RAPIDLY ONCE IT HAS ENTERED THE BODY
• WHITE BLOOD CELLS - TRAVEL AROUND BODY PATROLLING FOR PATHOGENS. WHEN THEY FIND AN INVADING MICROORGANISM, THEY CAN DO THREE THINGS:
• CONSUME THEM - ENGULF FOREIGN CELLS AND DIGEST THEM
• PRODUCE ANTITOXINS - COUNTER EFFECT OF ANY TOXINS RELEASED BY INVADING PATHOGENS
• PRODUCE ANTIBODIES - EACH PATHOGEN HAS UNIQUE MOLECULES ON THE EDGE OF ITS CELLS CALLED ANTIGENS. WHITE BLOOD CELLS CAN PRODUCE PROTIENS CALLED ANTIBODIES WHEN IT ENCOUNTERS FOREIGN ANTIGENS. ANTIBODIES LOCK ON AND KILL INVADING CELLS. THEY ARE UNIQUE TO THE PARTICULAR PATHOGEN - THEY WON'T LOCK ONTO ANY OTHER PATHOGEN
• ANTIGENS ARE THEN PRODUCED RAPIDLY TO FLOW ALL AROUND THE BODY TO KILL SIMILAR BACTERIA/VIRUSES
• SOME WHITE BLOOD CELLS STAY IN BLOOD AFTER PATHOGEN IS KILLED OFF - CALLED MEMORY CELLS. IF THE PERSON IS INFECTED AGAIN WITH THE SAME PATHOGEN, THE MEMORY CELLS WILL REMEMBER IT AND IMMEDIATELY MAKE PATHOGENS TO KILL IT - PERSON IS NATURALLY IMMUNE TO THAT PATHOGEN

VACCINATION

• VACCINATION - IMMUNISATION OF CERTAIN DISEASES
• DEAD OR INACTIVE PATHOGENS CARRYING ANTIGENS ARE INJECTED INTO THE BODY. THEY ARE HARMLESS BUT TRIGGER AN IMMUNE RESPONSE - WHITE BLOOD CELLS PRODUCE ANTIBODIES TO ATTACK THEM. MEMORY CELLS THEN STAY IN BLOOD SO THAT IF LIVE PATHOGENS OF THE SAME TYPE ENTER THE BODY, WHITE BLOOD CELLS WILL PRODUCE ANTIBODIES IMMEDIATELY

TYPES OF IMMUNITY

• ACTIVE IMMUNITY - IMMUNE SYSTEM MAKES ITS OWN ANTIBODIES AFTER BEING STIMULATED BY PATHOGENS - USUALLY PERMANENT
• PASSIVE IMMUNITY - ANTIBODIES ARE MADE BY ANOTHER ORGANISM E.G. PASSED ON BY MOTHERS BREAST MILK - TEMRORARY

BENEFITS

• STOPS ONE GETTING ILL
• MEANS THAT DISEASE WON'T BE ABLE TO SPREAD AS EASILY IF LOTS OF PEOPLE ARE IMMUNISED

RISKS

• SHORT TERM SIDE EFFECTS E.G. SWELLING AROUND INJECTED AREA OR FEELING UNDER THE WEATHER
• YOU CAN'T HAVE SOME VACCINATIONS IF ONE IS ALREADY ILL, ESPECIALLY IF IMMUNE SYSTEM WEAKENED
• A STUDY SUGGESTED THAT MMR VACCINE WAS LINKED TO AUTISM. SCIENTISTS HAVE NOW PROVED THAT IT IS SAFE BUT SOME PEOPLE STILL THINK THAT IT CAN CAUSE OTHER DISORDERS AND ARE NOT PREPARED TO TAKE THE RISK

ANTIBIOTICS

• DRUGS THAT KILL BACTERIA WITHOUT KILLING OWN BODY CELLS - DON'T KILL VIRUSES
• SOME BACTERIA ARE NATURALLY RESISTANT TO CERTAIN ANTIBIOTICS. OVER PRECRIPTION OR NOT FINNISHING A COURSE INCREASES RATE OF DEVELOPEMENT OF RESISTANT STRAINS

CANCER

• CAUSED BY CELLS DIVIDING OUT OF CONTROL
• BENIGN TUMOUR - CELLS STAY WHERE THEY ARE AND DON'T SPREAD - NOT NORMALLY DANGEROUS
• MALIGNANT TUMOUR - CAN SPREAD TO OTHER PARTS OF BODY - DANGEROUS

STAGES OF DRUG TESTING

• COMPUTER MODELS - STIMULATE HUMAN REACTIONS TO DRUG - USED TO IDENTIFY PROMISING DRUGS TO BE ESTED IN THE NEXT STAGE - NOT AS ACCURATE AS SEEING EFFECTS ON LIVE ORGANISM
• HUMAN TISSUES - CAN'T BE USED TO TEST DRUGS THAT EFFECT WHOLE BODY SYSTEM
• ANIMALS - LAW IN UK STATES THAT ANY NEW DRUG MUST BE TESTED ON TWO DIFFERENT LIVE MAMMALS - SOME PEOPLE THINK ITS CRUEL, OTHERS THINK IT'S THE SAFEST WAY TO ENSURE A DRUG ISN'T DANGEROUS

CLINICAL TRIALS

• TWO GROUPS OF PATIENTS - ONE GIVEN NEW DRUG, ONE GIVEN PLACEBO - DOCTORS CAN SEE ACTUAL DIFFERENCE THAT THE DRUG MAKES - ALLOWS FOR PLECEBO EFFECT
• SOMETIMES DRUG IS TESTED AGAINST BEST EXISTING TREATMENT RATHER THAN PLACEBO TO COMPARE
• BLIND - PATIENT DOESN'T KNOW WHAT THEY'RE GETTING
• DOUBLE BLIND - NEITHER PATIENT OR SCIENTIST KNOWS UNTIL RESULTS HAVE BEEN GATHERED

BODY IS DEFENDED AGAINST PATHOGENS

• SKIN PROVIDES BARRIER
• BLOOD CLOTTING PREVENTS ENTRY OF PATHOGENS
• PATHOGENS TRAPPED IN MUCUS IN AIRWAYS
• HYDROCHLORIC ACID IN STOMACH KILLS PATHOGENS

THE EYE

• CORNEA - REFRACTS LIGHT INTO THE EYE
• IRIS - CONTROLS HOW MUCH LIGHT ENTERS THE PUPIL
• LENS - REFRACTS LIGHT, FOCUSING IT ONTO THE RETINA
• RETINA - LIGHT SENSITIVE, COVERED IN DETECTORS CALLED RODS AND CONES WHICH DETECT LIGHT
• RODS - SENSITIVE TO DIM LIGHT BUT CAN'T SENSE COLOUR
• CONES - SENSITIVE TO DIFFERENT COLOURS BUT NOT GOOD IN DIM LIGHT
• OPTIC NERVE - CARRIES IMPULSES FROM RECEPTORS TO BRAIN

FOCUSING

• EYE FOCUSES LIGHT BY CHANGING SHAPE OF LENSE
• DISTANT OBJECTS - CILIARY MUSCLE RELAXES, SUSPENSORY LIGAMENT PULLS TIGHT - PULLS LENSE INTO LESS ROUNDED SHAPE - LIGHT REFRACTED LESS
• CLOSE OBJECTS - CILIARY MUSCLE CONTRACTS, SUSPENSORY LIGAMENT SLACKENS - LENSE BECOMES MORE ROUNDED - LIGHT REFRACTED MORE

• LONG SIGHTED - UNABLE TO FOCUS ON NEAR OBJECTS - OCCURS WHEN LENSE IS TOO LONG OR EYEBALL IS TOO SHORT - LIGHT NOT REFRACTED ENOUGH - IMAGE COMES INTO FOCUS BEHIND RETINA - CONVEX LENSE CORRECTS IT
• SHORT SIGHTED - UNABLE TO FOCUS ON FAR AWAY OBJECTS - LENS TOO ROUND OR EYEBALL TOO LONG - LIGHT IS REFRACTED TOO MUCH - IMAGE COMES INTO FOCUS BEFORE RETINA - CONCAVE LENSE OR CORNEAL LASER SURGERY CORRECTS IT

BINOCULAR VISION - TWO EYES THAT WORK TOGETHER

 BRAIN COMPARES IMAGES SEEN BY EACH EYE - MORE SIMILARITIES, FURTHER AWAY OBJECT - ALLOWS US TO JUDGE DISTANCES WELL BUT GIVES US NARROW FIELD OF VISION

CENTRAL NERVOUS SYSTEM - COORDINATES INFORMATION

• CONSISTS OF BRAIN AND SPINAL CHORD - MADE UP OF THREE TYPES OF NEURON - SENSORY NEURONS, RELAY NEURONS AND MOTOR NEURONS
• WHEN CHANGE IN ENVIRONMENT (STIMULUS) IS DETECTED, SENSORY NEURONS CARRY INFORMATION FROM RECEPTORS (E.G. LIGHT RECEPTORS IN BACK OF EYE) TO CNS
• CNS SENDS INFORMATION TO EFFECTOR (MUSCLE OR GLAND) ALONG A MOTOR NEURON

REFLEX ACTIONS

• NERVOUS SYSTEM USES ELECTRICAL IMPULSES TO ALLOW VERY QUICK RESPONSES - REFLEX ACTIONS ARE AUTOMATIC
• CONSCIOUS BRAIN NOT INVOLVED IN REFLEX ARC - SENSORY NEURON CONNECTS TO RELAY NEURON IN SPINAL CHORD WHICH LINKS DIRECTLY TO THE RIGHT MOTOR NEURON - NO TIME WASTED THINKING
• REFLEX ACTIONS OFTEN HAVE PROTECTIVE ROLE - E.G. SNATCHING BACK HAND FROM BURNING HOT PLATE

ELECTRICAL IMPULSES

• ELECTRICAL IMPULSE PASSED ALONG AXON OF CELL
• NEURONS HAVE BRANCHED ENDINGS (DENDRITES) SO THEY CAN CONNECT WITH LOTS OF OTHER NEURONS
• SHEETH ALONG AXON - ACTS AS ELECTRICAL INSULATOR - SPEEDS UP ELECTRICAL IMPULSE
• LONG - SPEEDS UP IMPULSE - (CONNECTING ONE NEURON TO ANOTHER SLOWS IMPULSE DOWN - QUICKER THAN HAVING LOTS OF SHORT ONES)

SYNAPSES

• ELICTRICAL IMPULSE TRIGGERS RELEASE OF TRANSMITTER CHEMICALS - DIFFUSE ACROSS GAP
• CHEMICALS BIND TO RECEPTOR MOLECULES IN MEMBRANE OF NEXT NEURONE WHICH TRIGGERS NEW ELECTRICAL IMPULSE
• STIMULANT DRUGS - INCREASE AMOUNT OF TRANSMITTER CHEMICALS AT SOME SYNAPSES - ICREASES FREQUENCY OF IMPULSES ACROSS SECOND NEURONE
• DEPRESSANTS - BIND TO RECEPTOR MOLECULES ON MEMBRANE OF NEURON 2 - BLOCKS ELECTRICAL IMPULSE - DECREASES BRAIN ACTIVITY

DRUGS - SUBSTANCES WHICH ALTER THE WAY THE BODY WORKS

MEDICALLY USEFUL DRUGS - E.G. ANTIBIOTICS - DRUGS YOU CAN BUY OVER THE COUNTER WITH PERSCRIPTION FROM DOCTOR

HARMFUL DRUGS 

• ADDICTION - PERSON HAS PHYSICAL NEED FOR DRUG, GETS WITHDRAWAL SYMPTOMS IF THEY DON'T TAKE IT - LEGAL DRUGS E.G. CAFFEINE AND ALCOHOL AS WELL AS ILLEGAL DRUGS CAN BE ADDICTIVE
• TOLERENCE - BODY GETS USED TO HAVING IT - NEED A HIGHER DOSE TO GIVE SAME EFFECT
• REHABILITATION - CAN HELP WITH ADDICTIONS - PERSON GETS HELP AND SUPPORT TO OVERCOME ADDICTION

ILLEGAL DRUGS

• CLASS A DRUGS - HEROIN, LSD, ECSTACY, COCAINE - DEALING RESULTS IN PRISON SENTENCE
• CLASS B DRUGS - CANNABIS, AMPHETAMINES
• CLASS C DRUGS - ANABIOTIC STEROIDS, TRANQUILLISERS - LESS SERIOUS - WARNING IF CAUGHT 

TYPES OF DRUGS

• DEPRESSANTS - E.G. ALCOHOL, TEMAZEPAM - DECREASE ACTIVITY OF BRAIN WHICH SLOWS DOWN RESPONSE OF NERVOUS SYSTEM - CAUSES SLOW REACTIONS AND POOR JUDGEMENT OF SPEED AND DISTANCES
• STIMULANTS - E.G. NICOTINE, ECSTACY, CAFFEINE - INCREASE ACTIVITY OF BRAIN - MAKES YOU FEEL ALERT, AWAKE - OFTEN USED TO TREAT DEPRESSION
• PAINKILLERS - E.G. PARACETAMOL, ASPIRIN - REDUCE NUMBER OF PAINFUL STIMULI AT NERVE ENDINGS NEAR AN INJURY
• PERFORMANCE ENHANCERS - E.G. ANABOLIC STEROIDS - SOMETIMES TAKEN BY ATHELETES - HELP BUILD MUSCLE TO HELP THEM TRAIN HARDER - BANNED BY SPORTS ORGANISATIONS
• HALLUCINAGENS - E.G. LSD - DISTORT WHATS SEEN AND HEARD BY ALTERING PATHWAYS THAT BRAIN SENDS MESSAGES ALONG

ALCOHOL

• DEPRESSANT - REDUCES ACTIVITY OF NERVOUS SYSTEM
• POSITIVES - MAKES PEOPLE FEEL LESS INHIBITED - IN MODERATION IT CAN HELP PEOPLE SOCIALISE AND RELAX
• LIVER CIRRHOSIS - ALCOHOL BROKEN DOWN BY ENZYMES IN LIVER - SOME PRODUCTS ARE TOXIC - OVER A LONG PERIOD OF TIME THESE PRODUCTS CAN CAUSE DEATH OF LEVER CELLS, FORMING SCAR TISSUE THAT STOPS BLOOD REACHING LIVER - LIVER CAN'T DO NORMAL JOB OF CLEANING BLOOD - CAUSES BUILD UP OF DANGEROUS SUBSTANCES IN BLOOD WHICH DAMAGES THE REST OF THE BODY
• ALCOHOL CAUSES DEHYDRATION - CAN DAMAGE OTHER CELLS IN BODY LIKE THE BRAIN
• BEING DRUNK LEADS TO IMPAIRED JUDGEMENT, POOR BALANCE, POOR COORDINATION, SLURRED SPEECH, BLURRED VISSION, SLEEPINESS - NOT ALLOWED TO DRIVE, FLY A PLANE OR OPERATE HEAVY MACHINERY WHEN DRUNK

SMOKING

• SMOKING IS ADDICTIVE AND CAUSES HEALTH PROBLEMS
• HEART DISEASE - CARBON MONOXIDE REDUCES OXYGEN CARRYING CAPACITY OF BLOOD - HEART DOESN'T RECIEVE ENOUGH OXYGEN - HEART ATTACK
• LUNG, THROAT, MOUTH AND OESPHAGEAL CANCER - TAR FROM SMOKE COLLECTS IN LUNGS - FULL OF CARCINOGENS - MAKE MUTATIONS IN DNA MORE LIKELY - CAUSES CELLS TO MULTIPLY OUT OF CONTROL AND CAUSE MALIGNANT TUMOURS
• SMOKERS COUGH AND SEVERE LOSS OF LUNG FUNCTION - DAMAGES CILIA ON EPITHELIAL TISSUE LINING THE TRACHEA, BRONCHI AND BRONCHIOLES - ENCOURAGES PRODUCTION OF MUCUS - EXCESS MUCUS CAN'T BE CLEARED IF CILIA DAMAGED - CLINGS TO AIR PASSAGES CAUSING SMOKERS COUGH - LUNGS ALSO LOSE ELASTICITY, LEADING TO EMPHYSEMA
• LOW BIRTH WEIGHT BABIES - LOW OXYGEN IN BLOOD OF PREGNANT WOMAN (CAUSED BY CO) - DEPRIVES BABY OF OXYGEN

HOMEOSTASIS - MAINTAINING A CONSTANT INTERNAL ENVIRONMENT

• CONDITIONS IN BODY NEED TO BE KEPT STEADY - CELLS NEED TO FUNCTION PROPERLY - INVOLVES BALANCING INPUTS WITH OUTPUTS
• LEVELS OF CO2 - RESPIRATION PRODUCES CO2 - NEED TO GET RID OF IT
• WATER CONTANT - BALANCE BETWEEN WATER YOU GAIN FROM DRINK, FOOD, RESPIRATION TO WATER YOU LOSE IN PEE, SWEAT AND BREATH
• BODY TEMPERATURE - GET RID OF EXCESS BODY HEAT WHEN TOO HOT, RETAIN HEAT WHEN TOO COLD

NEGATIVE FEEDBACK

 CHANGES IN ENVIRONMENT TRIGGER RESPONSE TO COUNTERACT CHANGES - INTERNAL ENVIRONMENT TENDS TO STAY AROUND A NORMAL (ENVIRONMENT THAT CELLS WORK BEST IN) - ONLY WORKS WITHIN CERTAIN LIMIT - TOO BIGGER CHANGE IN ENVIRONMENT - MAY NOT BE POSSIBLE TO COUNTERACT

THE BRAIN

• ENZYMES HAVE CONSTANT TEMPERATURE THAT THEY WORK BEST AT - ENZYMES IN HUMAN BODY WORK BEST AT 37 DEGREES
• THERMOREGULARITY CENTRE IN BRAIN - ACTS AS PERSONAL THERMOSTAT - CONTAINS RECEPTORS THAT ARE SENSITIVE TO BLOOD TEMPERATURE IN BRAIN AND RECIEVES IMPULSES FROM SKIN ABOUT SKIN TEMPERATURE - BRAIN CAN RESPOND TO THIS INFORMATION - INITIATES TEMPERATURE CONTROL MECHANISMS USING NERVOUS AND HORMONAL SYSTEMS

TOO HOT

• HAIRS LIE FLAT AND SWEAT PRODUCED (TRANSFERS HEAT FROM SKIN TO AIR WHEN EVAPORATES) 
• VASODILATION - BLOOD VESSELS NEAR SKIN SURFACE WIDEN - ALLOWS BLOOD TO FLOW NEAR SURFACE OF SKIN AND HEAT TO BE LOST

TOO COLD

• HAIRS STAND UP TO TRAP INSULATING LAYER OF AIR AND LITTLE SWEAT IS PRODUCES
• VASO CONSTRICTION - LESS HEAT TRANSFERED FROM BLOOD TO SURROUNDINGS
• SHIVER - MOVEMENT GENERATES HEAT IN MUSCLES

TOO HOT AND TOO COLD

• TOO HOT - DEHYDRATION - HEAT STROKE - DEATH
• TOO COLD - HYPOTHERMIA - DEATH

INSULIN

• GLUCOSE INPUT FROM GUT - EATING CARBOHYDRATES - CONTAIN GLUCOSE
• GLUCOSE TAKEN OUT - RESPIRATION AND VIGOROUS EXERCISE
• BLOOD WITH TOO MUCH GLUCOSE --> INSULIN RELEASED INTO BLOOD BY PANCREAS --> BLOOD GETS TO LIVER --> INSULIN MAKES LIVER TURN GLUCOSE TO GYCOGEN --> LIVER REMOVES GLUCOSE AND STORES IT AS GLYCOGEN FOR WHEN GLUCOSE LEVEL TOO LOW --> BLOOD GLUCOSE REDUCED
• BLOOD WITH TOO LITTLE GLUCOSE --> INSULIN NOT RELEASED --> BLOOD GETS TO LIVER --> LIVER TURNS GLYCOGEN STORE INTO GLUCOSE --> GLUCOSE ADDED BY LIVER --> BLOOD GLUCOSE INCREASED
• INSULIN - HORMONE - TRAVEL IN BLOOD - CAN TAKE A WHILE TO GET TO TARGET ORGAN 
• ELECTRICAL IMPULSE SENT ALONG NERVES TRAVEL MUCH FASTER - HORMONE RESPONSE SLOWER THAN NERVOUS IMPULSE RESPONSE

DIABETES - CAN'T CONTROL BLOOD SUGAR LEVEL

• TYPE 1 DIABETES - PANCREAS PRODUCES TOO LITTLE INSULIN - CAUSES GLUCOSE LEVEL TO RISE TO POINT WHERE IT CAN KILL THEM
• CAN BE CONTROLLED BY DIET AND INSULIN INJECTIONS AT MEALTIMES - INSULIN TAKES OUT GLUCOSE AS SOON AS IT ENTERS GUT IN DIGESTION - STOPS GLUCOSE LEVEL GETTING TOO HIGH - VERY EFFECTIVE - INSULIN DOSE DETERMINED BY PERSONS DIET AND ACTIVITY LEVEL
• TYPE 2 DIABETES - PERSON BECOMES RESISTANT TO INSULIN - BODY CELLS DON'T RESPOND PROPERLY TO HORMONE - OFTEN CAUSED BY LIFESTYLE
• CONTROLLED BY AVOIDING FOODS RICH IN SIMPLE CARBOHYDRATES

AUXINS - PLANT HORMONES WHICH CAN CONTROL GROWTH OF A PLANT - MOVE THROUGH PLANT IN SOLUTION

• PRODUCED IN TIPS - DIFFUSES BACKWARDS - STIMULATE CELL ELONGATION PROCESS WHICH OCCURS IN CELLS JUST BEHIND TIPS
• PROMOTES GROWTH IN SHOOT - INHIBITES GROWTH IN ROOT - INVOLVED IN GROWTH RESPONSES OF PLANTS TO LIGHT AND GRAVITY
• SHOOTS - POSITIVELY PHOTOTROPHIC - SHOOT TIP EXPOSED TO LIGHT - ACCUMULATES MORE AUXIN ON SHADED SIDE - CELLS ELONGATE FASTER ON SHADED SIDE - PLANT BENDS TOWARDS LIGHT
• NEGETIVELY GEOTROPHIC - SHOOT GROWS SIDEWAYS - GRAVITY MAKES MORE AUXIN ACCUMULATE ON LOWER SIDE - LOWER SIDE GROWS FASTER - BENDS SHOOT UPWARDS
• ROOTS - POSITIVELY GEOTROPHIC- ROOT GROWING SIDEWAYS - MORE AUXIN ON LOWER SIDE - AUXIN INHIBITES GROWTH IN ROOT - ROOT BENDS DOWNWARDS TOWARDS GROUND
• NEGATIVELY PHOTOTROPHIC - ROOT EXPOSED TO LIGHT - MORE AUXIN ACCUMULATES ON SHADED SIDE - AUXIN INHIBITES CELL ELONGATION IN SHADE - ROOT GROWS DOWNWARDS

AUXIN EXPERIMENTS

COMMERCIAL USE OF PLANT HORMONES

• SELECTIVE WEED KILLERS - DEVELOPED USING PLANT GROWTH HORMONES TO ONLY KILL BROAD LEAVED PLANTS AS OPPOSED TO NARROW LEAVED PLANTS LIKE GRASS - TOTALLY DISRUPT BROAD LEAF PLANTS GROWTH PATTERNS - KILLS THEM - LEAVES NARROW LEAF PLANTS UNTOUCHED
• GROWING FROM CUTTINGS - ALLOWS CUTTINGS TO PRODUCE ROOTS AND GROW INTO NEW PLANTS WHEN PUT INTO SOIL - ENABLES GROWERS TO PRODUCE CLONES OF GOOD PLANTS QUICKELY
• CONTROLLING RIPENING OF FRUIT - DELAY RIPENING OF FRUIT DURING TRANSPORT TO SHOPS - LESS EASILY DAMAGED - RIPENING HORMONE ADDED - FRUIT WILL RIPEN ON WAY TO SUPERMARKET
• CONTROLLINGDORMANCY - SEEDS WON'T GERMINATE UNLESS THEY'VE BEEN THROUGH CERTAIN CONDITIONS E.G. PERIOD OF COLNESS OR DRYNESS - GIBBERELLIN BREAKS DORMANCY - ALLOWS SEED TO GERMINATE - COMERCIAL GROWERS CAN MAKE SEEDS GERMINATE AT TIME OF YEAR THEY WOULDN'T NORMALLY

GENES AND CHROMOSOMES

• CELLS IN BODY HAVE NUCLEUS - CONTAINS GENETIC METERIAL IN FORM OF CHROMOSOMES - CHROMOSOMES COME IN PAIRS - DIFFERENT SPECIES HAVE DIFFERENT NUMBERS OF PAIRS E.G. HUMANS HAVE 23 PAIRS IN EACH NUCLEUS
• CHROMOSOMES CARRY GENES - DIFFERENT GENES CONTROL DEVELOPMENT OF DIFFERENT CHARACTERISTICS
• GENE - SHORT LENGTH OF CHROMOSOME - QUITE LONG LENGTH OF DNA
• DNA COILED UP TO FORM ARMS OF CHROMOSOMES
• ALLELES - DIFFERENT VERSIONS OF SAME GENE GIVE DIFFERENT CHARACTERISTICS E.G. BLUE- BROWN EYES

SOURCES OF GENETIC VARIATION

• GAMETE (SPERM AND EGG CELL) FORMATION - EACH PAIR OF CHROMOSOMES CONTAINS ONE CHROMOSOME INHERITED FROM MUM AND ONE FROM DAD - CHROMOSOMES SPLIT TO FORM GAMETES IN OVERIES AND TESTIES - CHROMOSOMES ALSO SPLIT - GAMETES HAVE HALF NUMBER OF CHROMOSOMES OF NORMAL BODY CELLS - JUST 23
• IN EACH GAMETE, SOME OF MUMS CHROMOSOMES GROUPED UP WITH SOME OF DADS - SHUFFLING UP OF CHROMOSOMES LEADS TO VARIATION
• FERTILISATION - SPERM AND EGG EACH WITH 23 CHROMOSOMES JOIN TOGETHER TO FORM CELL WITH 46 - FERTILISATION RANDOM - DON'T KNOW WHICH TWO CHROMOSOMES WILL JOIN
• MUTATIONS - CHANGES IN GENETIC CODE - CREATES NEW CHARACTERISTIC - INCREASES VARIATION
• FEATURES -DETERMINED BY GENES AND ENVIRONMENT
• HEALTH - SOME MORE LIKELY TO GET CERTAIN DISEASES BECAUSE OF GENES - LIFESTYLE ALSO EFFECTS HEALTH E.G. DIET AND ACTIVITY LEVEL
• INTELLIGENCE - MAXIMUM POSSIBLE IG DETERMINED BY GENES - WHETHER YOU GET TO IT DEPENDS ON ENVIRONMENT E.G. EDUCATION, UPBRINGING
• SPORTING ABILITY - GENES DETERMINE POTENTIAL - TRAINING ALSO IMPORTANT

GENETIC DIAGRAMS - SHOW POSSIBLE GENES OF OFFSPRING

• ALLELES - DIFFERENT VERSIONS OF SAME GENE 
• DOMINANT ALLELE - VERSION OF A CHARACTERISTIC THAT YOU SHOW
• RECESSIVE ALLELE - OTHER CHARACTERISTIC PASSED ON BY OTHER PARENT THAT YOU DON'T SHOW
• HOMOZYGOUS - TWO ALLELES THE SAME E.G. CC OR cc
• HETROZYGOUS - TWO ALLELES DIFFERENT E.G. Cc
• GENETIC MAKEUP - ALLELES YOU HAVE FOR PARTICULAR GENE - KNOWN AS YOUR GENOTYPE  - CHARACTERISTICS THESE ALLELES PRODUCE KNOWN AS PHENOTYPE

 ONE RED AND ONE WHITE - 4 HETROZYGOUS ALLELES

SEX INHERITANCE

• MEN HAVE AN X AND A Y CHROMOSOME - XY - Y CAUSES MALE CHARACTERISTIC
• WOMEN HAVE TWO X CHROMOSOMES - **
• 50:50 CHANCE OF HAVING BOY OR GIRL -TWO ** AND TWO XY RESULTS

GENETIC DISORDERS - CAUSED BY FAULTY GENES

• E.G. CYSTIC FIBROSIS - 1 IN 25 PEOPLE HAVE A RECESSIVE CYSTIC FIBROSIS ALLELLE
• RECESSIVE - PEOPLE WILL ONLY CARRY DISORDER AND NOT SHOW SYMPTOMS
• TWO PEOPLE WITH RECESSIVE ALLELE BREED - 25% CHANCE OF HAVING SOMEONE WHO SHOWS SYMPTOMS

ISSUES - SHOULD ALL FAMILY MEMBERS BE TESTED TO SEE IF THEY'RE CARRIERS? IS IT FAIR ON THEIR PARTNER IF THEY'RE NOT? IS IT RIGHT FOR SOMEONE CARRYING IT TO HAVE CHILDREN? IS IT FAIR TO PUT THEM UNDER PRESSURE NOT TO? IF A FEOTUS IS TESTED POSITIVE, IS IT RIGHT TO ABORT IT? FAMILY MAY NOT BE ABLE TO COPE BUT SHOULDN'T BABY HAVE A RIGHT TO LIFE?