biology b1

covers respiration, blood pressure, food and digestion.

?
  • Created by: anand
  • Created on: 03-05-10 11:25

respiration

Respiration:

respiration is the releasing of energy from glucose which happens constantly in all cells in living organisms.

there are 2 types of respiration.

aerobic respiration meaning with oxygen and anaerobic respiration meaning without oxygen.

the word equation for aerobic respiration is glucose+oxygen = carbon dioxide +water+energy.

the word equation for anaerobic respiration is glucose= lactic acid +energy.

the energy made in anaerobic respiration is less than in aerobic respiration because glucose is only partially broken down. there isn't enough oxygen for glucose to be fully broken down.

1 of 8

respiration

aerobic respiration is better than anaerobic respiration because:

1) it is the most efficient way to release energy from glucose.

2) it doesn't cause the build up of painful lactic acid in our muscles.

when we run a race we starts respiring aerobically. our heart and breathing rate increases to get more oxygen into our blood for faster respiration. unfit people respire anaerobically much quicker than fit people do because they can't get oxygen fast enough.

after the race our breathing rate stays high to replace oxygen lost. also our heart rate stays high to carry the lactic acid to the liver where it is broken down as soon as oxygen is available.

you also need to know the word equation. THIS IS THE BALANCED EQUATION.

C6H12O6+602 = 6CO2+6H2O+energy.

fit means how well you perform physical tasks. healthy means being free of any infections or diseases. DON'T GET THEM MIXED UP.

2 of 8

blood pressure

blood is pumped around the body under-pressure by the contraction of the heart. the blood needs to be pumped under-pressure so it reaches all parts of our organs in the body.

there are two types of pressure:

systolic pressure: maximum pressure the heart produces. (contract).

diastolic pressure: lowest pressure the heart produces. (relax).

blood leave through the arteries in the heart under-pressure and comes back through the vein with less pressure. the further away the blood goes from the heart the less pressure there is.

blood is measured in millimetres of mercury (mmHg).

high blood pressure causes blood vessels to burst, brain damage, strokes and kidney damage.

low blood pressure causes poor circulation of the blood, dizziness and fainting.

3 of 8

blood pressure

high blood pressure is caused by:

1) being overweight.

2) high stress levels.

3) alcohol.

4) smoking.

5) eating food high in salt, fat sugar etc.

6) age.

REMEMBER THESE 6!

4 of 8

food

a balanced diet is needed for a healthy lifestyle.

1) carbohydrates: provides energy.

2) fats: provides energy and acts as an energy store.

3) proteins: growth and repair of tissues. provides energy in emergencies.

4) vitamins: different vitamins help different things. e.g. vitamin C stops you from getting scurvy.

5) minerals: iron is needed to make haemoglobin for healthy blood.

6) water: replace water lost through sweating, urinating and breathing.

if we don't get all of these then we end up with a deficiency( meaning lack of).

5 of 8

food

lack of calcium= bone diseases like osteoporosis.

lack of protein= wasting of body tissue.

lack of iron= anaemia.

lack of vitamin C= scurvy.

lack of vitamin D= rickets.

lack of vitamin A= poor night vision.

energy varies from age, gender and active life.

age: children need more protein for growth.

gender: females need more iron to replace iron lost through the menstrual blood.

active life: people need more carbohydrates for energy which is used in their active life.

6 of 8

food

TOO MUCH FOOD CAUSES OBESITY WHICH CAUSES:

1) high blood pressure( which leads to more problems).

2) CHD (coronary heart disease).

3) arthritis.

4) cancer.

5) AND MORE SO DON'T EAT TOO MUCH. EXERCISE MORE.

recommended daily amount (RDA in g) of protein is calculated by this formula.

0.75 X body mass (in kg).

body mass index (BMI) can be used to find the weight range of a person.

body mass (in kg) DIVIDED BY height (in m) SQUARED. DON'T FORGET TO SQUARE.

7 of 8

digestion

digestion is the breaking down of big molecules into smaller molecules.

physical: chewing food in the mouth and churning it in the stomach.

chemical: breaking down large molecules into smaller molecules using enzymes.

DIGESTIVE ENZYMES BREAK DOWN OUR FOOD.

STARCH(CARBOHYDRATES) + CARBOHYDRASE = SIMPLE SUGARS(GLUCOSE).

PROTEIN + PROTEASE = AMINO ACIDS.

FATS + LIPASE = FATTY ACIDS AND GLYCEROL.

THE ENZYMES ARE CARBOHYDRASE, PROTEASE AND LIPASE.

8 of 8

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »