Human Growth & Development

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Human Growth and Development – Diet and Smoking

Many lifestyle factors can affect human growth and development including diet and smoking.

It is important to eat a balanced diet.
Your diet will also depend on how much exercise you do and your general lifestyle.
- The more you exercise the more calories your body will need.
Olympic swimmer Michael Phelps trained and exercised so much he had to eat about 10,000 calories a day.

Calories are the amount of energy in food and drink.
Calories are given on the packets of foods with the unit kcal.
- The average male will need 2500 calories a day.
- The average female will need 2000 calories a day.
To convert calories into kilojoules (kJ) multiply the number of calories by 4.2.

If you sit down all day you will need less calories to remain fit and healthy.
If you do not eat enough food you can become underweight.
- You can then starve which may lead to death.
If you eat more food than you should, you can become overweight and then obese.
- Obese people are at increased risk of type 2 diabetes, high blood pressure and high cholesterol as well as heart disease and strokes.

Around 14% of people in the UK smoke.
They are putting their health at risk.
- Cigarettes contains tobacco which contains harmful substances.

Tar -Blocks and damages the cilia in the airways causing the smokers to cough and damages the alveoli in the lungs making gas exchange more difficult.
Nicotine
- Nicotine is the chemical that makes smoking addictive.
- It can also increase blood pressure and narrow the arteries. Nicotine can also increase the risk of the heart attack.
Carbon Monoxide
- Is a colourless, odourless and tasteless gas.
- It replaces oxygen in the red blood cells which means the heart has to pump faster and harder to get oxygen around the body.

Carbon Monoxide
- Is a colourless, odourless and tasteless gas.
- It replaces oxygen in the red blood cells which means the heart has to pump faster and harder to get oxygen around the body.

Smoking can cause emphysema.
- This is when your air sacs (alveoli) are destroyed in the lungs.
- This reduces gas exchange.
Smoking can also cause bronchitis.
- This is damage to your airways.

Respiration is the process that releases energy. Smoking and drinking while pregnant can have severe effects on fetal development.

Respiration is a chemical reaction.
There are two types of respiration aerobic and anaerobic respiration.
- Anaerobic respiration is respiration that happens without oxygen.
- Aerobic respiration is respiration that requires oxygen.
It is important to remember respiration is not breathing.
Respiration occurs in the mitochondria of animal and plant cells.
Respiration releases energy.

The equation for aerobic respiration is:
Glucose + Oxygen --> Carbon dioxide + Water (+ Energy)
Animals
- Get glucose from the food they eat and breathe in oxygen.
- They breathe out carbon dioxide.
Plants
- Get glucose and oxygen from photosynthesis.

Pregnant women who drink, smoke, and take drugs put their unborn child at risk.
If you drink alcohol when you are pregnant the alcohol can pass through the placenta and affect the development of the baby.
- Advice is given that pregnant women should not drink at all.
You should not smoke when you are pregnant.
- Cigarettes contain over 4000 chemicals.
- Smoking when pregnant can restrict oxygen to the unborn baby.
Pregnant women should also stay aware from second hand smoke.

Drinking while pregnant increases the risk of:
- Miscarriage
- Premature birth
- Lower birth weight
- Foetal Alcohol Syndrome (FAS) – children with FAS may have lifelong behaviour and learning difficulties

Smoking while pregnant increases the risk of:
- Miscarriage
- Premature birth
- Lower birth weight
- Sudden Infant Death Syndrome (SIDS) or cotdeath

Pregnant women should also take care not to take drugs while pregnant – this includes illegal and legal drugs
Medicines and drugs can reach the unborn baby via the placenta
- If a pregnant women is not sure if she can take legal medicines like painkillers they should talk to their doctor.