Activities: activity-2

These changes in the brain and body make nicotine highly addictive. Other addictive drugs of abuse, including heroin and cocaine, cause the same changes in the brain.

F. Nicotine causes the same changes in the brain as heroin and cocaine.

In 40 minutes, half the effects of nicotine are gone. So smokers get the urge to light up for another dose of the drug. After repeated doses of nicotine, the brain changes. To adjust to too much dopamine, the brain cuts production of the neurotransmitter and reduces the number of some receptors. Now, the smoker needs nicotine just to create normal levels of dopamine in his or her brain. Without nicotine, the smoker feels irritable and depressed. The smoker has trained the limbic system to crave tobacco.

E. Without nicotine, a smoker feels happy and calm.

Nicotine stimulates neurons to release unusually large amounts of dopamine. Dopamine stimulates the brain's pleasure and reward circuit, a group of brain structures called the limbic system involved in appetite, learning, memory, and feelings of pleasure.

D. The limbic system is the brain's pleasure and reward circuit.

Nicotine also attaches to neurons (brain cells) that release a neurotransmitter called dopamine.

C. Neurons are also referred to as dopamine.

Nicotine raises the heart rate and respiration (breathing) rate, and causes more glucose, or blood sugar, to be released into the blood.

B. A person's blood sugar and breathing rate are both increased by nicotine.

Nicotine is the drug in tobacco leaves. Whether someone smokes, chews, or sniffs tobacco, he or she is delivering nicotine to the brain.

A) Nicotine is a drug.

8) Nicotine is a chemical found in tobacco that is _______________.