Diet and Exercise
Carbohydrates + Fats:
Proteins + Vitamins + Minerals:
Grow and replace damaged cells and tissues
Malnutrition occurs when you either eat too much or too little of a nutrient.
Metabolism is the speed at which your body digests food, this is also known as your Metabolic rate. Regular exercise increases your Metabolic Rate
Cholesterol is a fatty substance that is in our blood stream; we need it to keep our body cells to function properly. Blood cholesterol levels depend on the amount of fat in the diet.
Atkins Diet, Weight Watchers, Slim-Fast Diet and Cabbage Soup Diet
Only one slimming pill has been approved by the NHS; Orlistat
"Orlistat works by inhibiting enzymes that digest fat. Nearly a third of the fat that you eat is not digested if you take Orlistat. The undigested fat is passed out with your faeces. Studies have shown that Orlistat, plus a mass-reducing diet and exercise, causes mass loss than a mass-reducing diet and exercise alone. Some people lose 10% or more of their body mass within six months with the help of Orlistat. In others, it is less effective."
In hospitals up to 5000 people die a year from having hygiene rules broken, such as having curtains not changed, dirty needles not being properly disposed of and doctors and nurses not always washing their hands, or using hand gel
Microorganisms are tiny living things that are everywhere, including food. The ones that cause ilnesses or diseases are types of Pathogens
Ignaz Semmelweiss was a doctor in the mid-1800's and saw that doctors carrying out work on corpses did not wash their hands before they delivered a baby; these women usually died from childbed fever. When he got the doctors to wash their hands fewer women died
Louis Pasteur and Joseph Listeur studied Semmelweiss's research and from that studied objects that soon became known as microorganisms. Pasteur then proved there were germs in the air that carried diesease and infection
Antiseptics are used to clean wounds or rid of sores, Disenfectants however clean work surfaces
Bacteria and Viruses can be spread by air, food, liquids and by touch.
Defence against Diseases
Bacteria and Viruses make you ill by relasing poisinous chemicals called toxins. As such you might get symptoms such as headaches, fever or feeling sick
Bacteria multiply in your body rapidly while Viruses need to enter a cell to begin to multiply. Viruses make copies of themselves and the new Viruses burst out of the cell, therfore damaging or even destroying the cell, and this is what can make you feel ill
White blood cells ingest the pathogen by surrounding it then engulfing it, or produce anti-bodies to destroy the pathogens for them, they also produce anti-toxins which prevent the poisionus chemicals from poisioning your body
Treating and Preventing Diseases
Antibiotics are medicines that help cure disease caused by Bacteria. Pennicilian was the the first ever antibiotic to be discovered by Alexander Flemming. Antibiotics however cannot kill Viruses
Immunisation vaccines usually invloves injecting or swallowing a vaccine containing small amounts of dead or weak pathogen. Because the pathogen is usually weak or dead it does not make you ill, but your white blood cells still produce anti-bodies to destroy it anyway. This makes you immune to the pathogen.
The Nervous System is made up of three main parts, the Brain, the Spinal Cord and Neurones.
It has receptors in the eyes that are sensitive to light, ears that are sensitive to sound, the tongue and nose that are sensitive to chemicals that let us taste and smell, and the skin that are sensitive to touch, pain, pressure and temperature
There are three types of Neurones,
Sensory Neurones: Carry impulses from the receptor to the spinal cord.
Relay Neurones: Carry impulses through the spinal cord and up to the brain and back along
Motor Neurones: Carry impulses from the spinal cord to the effector
The Menstrual Cycle:
Every month, an egg (ovum) develops inside a female ovary. At the same time, oestrogen causes the lining of the womb (uterus) to become thicker, ready to receive a growing embryo. If the egg is not fertilised, the womb lining breaks down, causing bleeding from the vagina. The monthly cycle of chnages that take place in the ovaries and womb is called the menstrual cycle. The menstrual cycle is controlled by several hormones.
FSH (follicle stimulating hormone) produced by pituary gland in brain, FSH makes ovary produce follicle and the follicle then produces oestrogen. The oestrogen then makes the uterus prepare for a fertilised egg, which triggers the release of LH (lutinising hormone). After the egg is released the LH causes the follicle to turn into a corpus leteum and produce progesterone, that then helps maintain the womb lining.
The contraceptive pill contains hormones that have the same effect on the pituary gland as oestrogen. These hormones stop the pituary gland making the hormone FSH. This means no eggs will mature in the ovaries.
Benefits and Problems
The first contraceptive pills contained a large amount of oestrogen relsuting in mnay women having blood clots. There are two types now available, mini and combined. The combined has a lower dose of oestrogen with progesterone, while the mini only has progesterone. The mini has fewer side effects but is less reliable.