Ch-15 DRUGS Flashcards Preview

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Flashcards in Ch-15 DRUGS Deck (16)
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What is a Drug?

A drug is any substance taken into the body that modifies or affects chemical reactions in the body


Brief Antibiotics

Antibiotics are chemical substances made by certain fungi or bacteria that affect the working of bacterial cells, either by disrupting their structure or function or by preventing them from reproducing.

effective against bacteria but not against viruses.
some bacteria that cause disease have become resistant to antibiotics and this reduces the effectiveness of prescribed antibiotics when someone has a bacterial infection


Why don't Antibiotics Affect Viruses?

This is because antibiotics work by disrupting cell functions such as respiration, or breaking down the structure of the cell in some way
However, viruses do not carry out any cell functions and do not have cell walls, cell membranes or any cell organelles as viruses infect and utilise the machinery of animal cells to reproduce, which are not affected by antibiotics.


Ways individuals can help prevent the incidence of antibiotic resistance increasing include:

only taking antibiotics when absolutely essential
when prescribed a course of antibiotics, ensure that the entire course is completed even if you feel better after a few days


What are the effects of alcohol consumption?

- Increases reaction times
- vomiting- as it it is toxic for the body
- damages the brain causing memory loss and confusion
- long time consumption damaging the liver
-reduced self- control, the person may become violent.


What is the site of breakdown of alcohol and other toxins?

it has enzymes that break down alcohol but the products of the reactions involved are toxic and over time, the liver can be irreparably damaged


Explain, how can injecting heroin cause HIV?

As syringe needles cost money, heroin addicts may share needles which increases the risk of transmission of blood-borne infections such as HIV


How does Heroin Affect the Nervous System?

In the brain there are many different chemical neurotransmitters that transfer nerve impulses across synapses
The neurotransmitters diffuse across the synapse and fit into receptor molecules on the postsynaptic membrane
One group of neurotransmitters is called endorphins which help to reduce sensations of pain, affect mood and reduce sensations of hunger and thirst
When it enters the brain, heroin is metabolised to morphine
Morphine molecules fit into some of the endorphin receptors and this is why taking heroin makes users feel so good
Taking heroin can reduce the production of natural endorphins and other neurotransmitters, which is why repeated use leads to the need for greater and greater amounts in order to get the same feelings


What diseases does smoking cause?

chronic obstructive pulmonary disease, COPD
coronary heart disease
lung cancer


What are the chemicals found in the cigarettes' ?

Tar – a carcinogen (a substance that causes cancer))
Nicotine – an addictive substance which also narrows blood vessels- increasing BP and causing strain on the vessels
Carbon monoxide – reduces the oxygen-carrying capacity of the blood


Effect of Tar on the gas exchange system?

Contains carcinogens which can cause cancer.
These chemicals can affect the behavior of some cells in the respiratory passages and the lungs, causing them to divide uncontrollably
High cell division from a lump/tumor. If this tumor if malignant, this is cancer.
Cells could break from this tumor, and spread into the body where it will develop more tumors.


Effect of nicotine on the gas exchange system?

Nicotine narrows blood vessels increase blood pressure
Narrow blood vessels are more likely to become clogged with fat, including cholesterol – if this happens in the coronary artery, this causes coronary heart disease
This means the heart muscle cells do not get sufficient oxygen and so less aerobic respiration takes place
To compensate the cells respire anaerobically, producing lactic acid which cannot be removed (due to lack of blood supply)
This creates a low pH environment in the cells causing enzymes to denature and eventually heart muscle cells will die
If enough die this can cause a heart attack


Name the two hormones that are used to enhance sporting performance?

- testosterone
- anabolic steroids


Name the two hormones that are used to enhance sporting performance?

- anabolic steroids
- testosterone


effects of testosterone.

cause more proteins to be made in muscles so that muscles become larger and stronger


effects of anabolic steroids.

increases muscle mass, helps athletes train harder and for longer periods of time, and can increase aggression which can give an edge when competing