Quick test  1) What happens to the diaphragm and rib muscles when you inhale?  2) Write the word equation for respiration?  3) What is the chemical found in the nucleus of cells

Objectives 1) To see the diseases caused by smoking 2) To look at the main things in cigarette smoke that cause the damage.

DRINKING & SMOKING

Non-smoker Smoker with Emphysema

Mouth cancer Lung cancer Throat cancer Cancer of the oesophagus

A human heart that has suffered a heart attack. This was brought about by smoking. A blocked coronary artery

Cigarette smoke  Tobacco smoke contains the drug NICOTINE which is a stimulant and is very addictive. It is this addiction to nicotine that makes it so difficult to give up smoking.  Nicotine affects the circulatory system by making blood vessels get narrower. This increases blood pressure which puts extra strain on the heart. Nicotine increases the risk of a heart attack or a stroke.

Cigarette smoke  CARBON MONOXIDE decreases the amount of oxygen that can be carried in the blood.  Oxygen is transported by haemoglobin inside red blood cells. But haemoglobin combines much more readily with carbon monoxide than with oxygen.  Once it has combined, it is very reluctant to let the carbon monoxide go. So a lot of the haemoglobin of a smoker is taken out of action, permanently combined with carbon monoxide.  Less oxygen is delivered to tissues.

Smoking whilst pregnant  Both nicotine and carbon monoxide can harm the development of a foetus in a woman’s uterus.  Both of them can cross the placenta and get into the baby’s blood. This has a similar effect to the fetus smoking a cigarette!  The baby is likely to be smaller than average at birth and more likely to suffer several diseases.

Diseases caused by smoking 1-4) Write down as many different diseases caused by smoking as you can remember 1.Emphysema 2.Heart disease 3.Cancer (Lung, mouth, throat) 4.Bronchitis

Nicotine  Nicotine is a very addictive drug it is also a stimulant.  Nicotine also makes blood vessels narrower so that less blood can get to cells. This can cause high blood pressure and heart disease.

Smoking Carbon monoxide Carbon monoxide from cigarette smoke attaches to haemoglobin molecules in the red blood cells and prevents them from transporting oxygen.

Pregnancy  If a pregnant woman smokes the foetus may not get enough oxygen and be born prematurely.

Recap

Cigarette smoke  Tar contains chemicals that are CARCINOGENS – substances that can cause cancer. Carcinogens in tar cause genes to mutate, which can make cells begin to divide out of control.  Even low tar cigarettes contain enough carcinogens to seriously increase the risk of getting cancer.

Cigarette smoke  PARTICULATES are tiny pieces of carbon and other materials.  They cause irritation in the lungs.  White blood cells try to remove them. White blood cells and other protective cells secrete chemicals that are supposed to help to defend the person against pathogens, but in this case they often do a lot of harm to other body cells.

Ciliated epithelial cells

Smoker’s Cough  The mucous membrane in the trachea and bronchi helps to stop bacteria and other particles getting down into the lungs.  Unfortunately, carbon monoxide and other chemicals in tobacco smoke stop this system from working.  They stimulate goblet cells to make even more mucus and, at the same time, stop the cilia from beating.  This extra mucus just trickles down and accumulates in the lungs.  This is why smokers cough – they are trying to get rid of the mucus.

Cilia and smoking

Bronchitis  Bacteria accumulate in the lungs and bronchi as they breed in excess mucus.  They cause inflammation and the person has BRONCHITIS  Smokers often develop chronic bronchitis.

Emphysema  The constant coughing damages the delicate walls of the alveoli. Other chemicals in the smoke cause the walls of the alveoli to break down.  This reduces the surface area across which oxygen and carbon dioxide can be exchanged with the blood.  The smoker needs to breathe faster to get enough oxygen into the blood, developing a condition known as emphysema.

TO DO… 1) Complete smoking 2 2) Stick the ciliated epithelial cells seet in your book and add the threee missing labels

Ciliated epithelial cells

Smoking Tar  Tar can line the alveoli reducing gas exchange.  Tar contains chemicals that cause cancer (carcinogens)

 Tiny pieces of carbon and other materials (particulates) cause irrition and damage in the lungs. White blood cells try to remove them but unfortunately the chemicals they produce do more harm than good.

 The tar in cigarette smoke paralyses the cilia in the windpipe so that they stop working.  Bacteria, particulates & mucus build up in the lungs.  Bacteria cause infections such as bronchitis.  Mucus and dirt in the bronchi and bronchioles make you cough.

Q. What do we mean by chronic bronchitis, how does this cause emphysema?

 Discuss with your partner the most important thing you’ve learned today in this lesson

Normal liverCirrhotic liver

The liver breaks down toxins in the body. In the process, the liver’s own cells become damaged leading to a condition known as CIRRHOSIS, which can kill!

Alcohol  Alcohol is a depressant and slows down the parts of the brain that are involved in decision making and coordination of movement.  It causes the blood vessels in the skin to dilate, which allows more heat to be lost. (People have died from hypothermia after getting drunk and falling asleep outside in the cold)  There is also a heightened risk of heart disease as alcohol increases blood pressure.