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  • Created by: l11n
  • Created on: 01-02-16 15:58

Fitness and health

Health- Free from infection and disease

Fitness-How well you can perform physical tasks

Fitness= strength,speed.agility,flexibility,stamina

Stamina= cardiovascular efficiency (How well heart and pump oxygen to muscles)

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Blood pressure

Blood is pumped by contractions of the heart. 

Contractions increase bood pressure

Blood leaves  heart and flows through arteries,

Ateries split into capillaries 

Capillaries take blood to every cell 

Blood flows back to the heart through veins

Blood pressure is high when heart contracts (Systolic pressure- approx 135)

Blood pressure is low whe heart relaxes  (Diastolic pressure-approx 85)

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High and low blood pressure

Increases blood pressure:                               

  • Smoking (carbon monoxide combines with Haemoglobin and red blood cells carry less oxygen so heart has tocontract more often to supply oxygen . Nicotine increases heart rate which increases contracts.)                                            
  • Overweight   (salt increases blod pressure and risk of damage to arteries can lead to heart attack)                                            
  • Stress                                         
  • Alcohol               

High blood pressure problems                                Low pressure problems

  • Blood vessels burst                                           Poor circulation
  • Strokes                                                              Dizziness
  • Brain damage                                                    fainting
  • Kidney damage                                        
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Heart attacks/disease

How saturated fats cause a heart attack

  • Saturated fats = high level of cholesterol
  • Cholesterol used for cell membrane, excess=plaques in ateries
  • Plaques narrow the ateries ,ristricts the flow of blood

How narrow ateries increase risk of heart attack 

  • Heart supplied with blood from the coronary arteries 
  • plaques narrow these 
  • Blood flow to the heart is restricted, muscles recieve less oxygen
  • Thrombosis (blood clot) also restircts blood flow
  • Thrombosis and plaques can cut off all flow of blood 
  • Heart muscle recieves no oxygen 
  • Heart attack
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The six essential nutrients

Carbohydrates (made up of simple sugers eg glucose) - Provide  energy 

Fats (made up of fatty acids and glycerol)-  Provide energy and insulation 

Proteins (made up of amino acids) - growth and repair of tissue, energy in emergencies

  • Essential amino acids arent made in the body but found in diet
  • Animal protiens contain all essential amino acids plant proteins don't.
  • Vegetarians have to eat a wide range of plant bc of this
  • Animal proteins are first class proteins , plant protiens are second.

Vitamins and minerals-various functions depending on the mineral/vitamin

  • Vitaminc -prevent scurvy 
  • iron to make haemoglobin 

Water- prevent dehydration

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Diets

Factors that affect a balanced diet

  • Age - Teenagers need more protein for growth , elderly need more calcuim to protect against bone disease.
  • Gender- females need more iron to replace iron lost in menstural blood.
  • Physical activity-active people need more protein for muscle development an d carbohydrates for energy.

Other reasons

  • Religion 
  • Personal reasons- vegetarians, cruelty to animals
  • Medical reasons- food intolerance to certain foods, 
  • Allergy- ( dont make the enzyme to digest that food)
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Diet problems

Kwashiorkor

  • Too little protein 
  • common symptom - swollen stomach
  • In developing countries where overpopulation means theres not enough protein rich foods for everyone
  • Not enough money in those countries to invest in farming so its difficult to produce enough protein rich foods without right techniques

Eating disorders

  • Anorexia nervosa- self starvation, caused by low self esteem and poor self imagine
  • Bulimua nervosa- binge eating folowed by self induced vomiting (lead to tooth decay- acid in vomit eats aay at tooth enamel)

Lead to: liver failure, kidney failure,heart attacks,muscle wastage,low blood pressure.

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EAR and BMI

Estimated average daily requirement 

EAR(g)= 0.6 X Body Mass (kg)           

only an estimate and varies from person to person 

Body mass index 

BMI= Body mass (kg)                                                                                                                                      (height)2

BMI

  • below 18.5 -> underwight
  • 18.5-24.5   -> normal 
  • 25-29.9     ->  Overweight
  • 30-40       ->  moderately obese
  • above 30 ->   severly obese
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Pathogens

Pathogens are microorganisms that cause disease

  • Fungi- athlete's foot
  • Bacteria - Cholera
  • Viruses- Flu
  • Protozoa (single celled organisms)-dysentery

Symptons of an infectious disease are caused by cell damage or by toxins produced by the pathogens

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Malaria

  • Caused by a protozoan a parasite- an organism that lives off another organism (the host)
  • Carried by mosquitoes
  • Mosquitoes are vectors- carry disease without getting it themselves
  • Pick up malarial parasite when they feed on an infected animaland passes it on when it ffeds on another animal by inserting into the animals blood vessels

Reducing the spread of infection 

  • areas of water where mosquitoes lay their eggs can be drained and sprayed with insecticides
  • fish can be put in to eat mosquito larvae
  • people can use insecticides and mosquito nets
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Dealing with pathogens

Pathogens reproduce rapidly when they enter your body. 

White blood cells travel in your blood looking for parasites when they find one they:

  • engulf the cells and digest then 
  • Produce antitoxins to cancel the effects of toxins the pathogens produce

Produce anti bodies

  • every pathogen has unique antigens on its surface
  • when white blood cells see a forgien antigen they produce a specific antibody for that pathogen 
  • Antibodies are then produced rapidly and kill similar pathogens
  • some white blood cells stay around after the pathogen has been fought off these are memory cells 
  • if the person is infected with the same pathogen these cells will rmemeber and immediately make pathogens to kill it 
  • the person naturally becomes immune to that pathogen 
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Immunisation

  • Immunisation involves injecting dead or active pathogens into the body 
  • They carry antigens even though they are harmless they will make white blood cells produce antibodies
  • White blood cells will remian in the blood as memory cells
  • If live pathogens enter the antibodies will be made immediately

Active immunity 

  • When the immune system makes its own antibodies after being stimulated
  • Active immunity is usually permanent

Passive immunity 

  • When you use anitbodies made by another organsim eg antibodies passed to a baby from breast milk. 
  • It is temporary 
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