B1- OCR Gateway Biology Science

  • Created by: Georgia
  • Created on: 29-12-11 18:51



Healthy- no infections or disease

Fit- how well you can perform physical tasks… strength, speed, agility, flexibility, stamina

Cardiovascular efficiency- ability of heart to supply muscles with oxygen… measured by stamina

Blood pressure- pressure is needed to pump blood to body parts…




Low blood pressure -poor circulation -tissues get less food and oxygen fainting


High blood pressure   -smoking       -overweight      -too much alcohol       -stress

Blood vessels burst     -strokes     -brain damage     -kidney damage


Smoking- carbon monoxide combines with haemoglobin in red blood cells, instead of oxygen- heart rate has to increase to get enough oxygen to tissues… heart contracts more… increases blood pressure.

· Nicotine increases heart rate… heart contracts more often… increases blood pressure.


Poor diet- cholesterol=fatty substance and high salt levels

Some cholesterol for making cell membranes… too much- build up in arteries

Makes plaques in artery wall… narrow arteries- restricts blood flow… heart attack.


Narrow arteries… 1) heart muscles supplied with blood- coronary arteries

                                 2) narrowed- blood flow restricted… heart muscle gets less oxygen

                                3) a thrombosis (blood clot) also restricts blood flow

                                4) if a thrombosis occurs in an already narrow coronary artery, blood flows to the heart might be blocked completely

                                5) area of heart muscle will be cut off from oxygen supply- heart attack 


Balanced diet- supplies all essential nutrients



Made of



Provide energy

Simple sugars e.g. glucose

Liver as glycogen OR converted to fats


Provide energy store, insulations

Fatty acids and glycerol

Under skin OR around organs as adipose tissue


Growth and repair of tissue, emergency energy

Amino acids

Not stored

Vitamins and minerals

Various functions e.g. vitamin C prevents scurvy; iron (mineral) makes haemoglobin for healthy blood




Prevent dehydration




Some amino acids- not made by body… have to get from diet- essential amino acids.

All essential amino acids can be attained by eating meat (produced by animals) - first class proteins.

Plant proteins don’t contain all essential amino acids- second class proteins.

Diet factors-

Children and teenagers-more protein needed for growth

Older people- more calcium to protect from degenerative bone diseases e.g. osteoporosis.


Active people- more protein for muscle development and more carbohydrate for energy

Females need more iron- iron lost in menstrual blood














Different diets… religious, e.g. Hindus don’t eat cows, sacred… personal, e.g. vegetarians, cruel to eat meat… medical reasons, intolerance or allergies


Too little protein- kwashiorkor… swollen stomach

Overpopulation- demand for protein-rich food is more than amount that’s available

Money- not enough to invest in agriculture… without good farming techniques cannot grow enough protein-rich food


EAR (Estimated Average daily Requirement) of protein (g) = 0.6 x body mass (kg)

Teenagers- more, growing

Pregnant and lactating women- more, baby needs it


Anorexia and bulimia… poor




wow! Perfectly clear and concise notes on B1! This is very useful! Thanks for putting the effort into it and making such a good resource :)



this is amazing, very helpful! thank you so much!! 



You're very welcome, glad it helped :) 



how do I get the pictures on?