Biology revision


Biology Revision

Fitness and Health

Fitness is someones ability to do physical activity

We can measure fitness on these terms:

  • Stamina
  • Cardiovascular health
  • speed
  • agility
  • flexability

Health is being free from disease.

Blood Pressure

Ideal Blood Pressure:  120/80

120 is the systolic pressure, which is the pressure when the heart contracts.

80 is the diastolic pressure, which is the pressure when the heart relaxes.

Heart Health

Smoking causes increased blood pressure, because it contains carbon monoxde, which blocks red blood cells fgrom picking up oxygen by binding to the haemoglobin. It also contains nicotine, which increases the heart rate.

Saturated fat causes bad heart health because it increases the livers production of cholestoral, (which leads to thrombosis) this increases the blood pressure and the risk of heart disease.

Health and Diet

food nutrient          Why do you need it           where is it stored             examples 

Protein                   strength growth repair             not stored                    beef/chicken

Carbohydrate         energy                               liver/ muscles                    pasta

water                      hydration                                not stored                     water

Fibre                      helps heart/digestive s.           not stored                     fruit, veg, wheat

vitamins                 prevents scurvy                       not stored                    oranges

Minerals                prevents anemia                      not stored                     iron

fat                         energy, protect organs          adipose tissue                butter

Most fats are made up of triglycerides:

triglycerides = (glycerol + 3 fatty acids)

BMI: body mass index

Weight (KG)

Height x Height (m)


1st class protein is a protein made from the essential amino acids (found in proteins) that our body cannot make

2nd class protein is a protein made from non essential amino acids that our body can make.

Infectious and Non-Infectious diseases

Infectious                                 Non-Infectious

- caused by                              - Not caused by parasites

micro-organisms                      - Could be a deficiency

- They live in the body             - Irlens syndrome

- They feed off host                 - Asthma


Kwashiokor is a non-infefctious disease. It is a protein deficiency, often found in countries experiencing famine and natural disasters.

Bacteria: Cholera

Viruses: Flu

Fungi: Athletes foot

Protozoa: Malaria

Immunity and Immunisation

Pathogens can be kept out by:

  • skin
  • tears
  • mucus
  • stomache acid
  • sneezng

Antigen chemicals are found on the surface of the pathogen. Each antigen has a different pathogen. mphocytes carry antibodies. When lymphocytes destroy pathogen, they use the antibodies they carry. They engulf the pathogens and release enzimes to kill them.

white blood cells

Pathogens enter the body. This causes a message to be sent to the brain. When this message is recieved, Lymphocytes are relaeased. When the pathogen and Lymphocytes meet, they come together. the Lymphocytes engulf the pathogens and release enzimes to kill them. Once this process is complete, all of the immunised pathogen are put together by the lymphocytes. This is when the phagocytes are released. The phagocytes ingest the pathogens.

active immunity is when your body makes its own antibodies. Passive immunity is when your body does not make its own antibodies.

The eye

Iris: can change the size to…


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