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A Describe the mode of action of recreational drugs and the effects on the body of their repeated use - Scottish Highers Human Biology - Question 15 - 2023
Question 15
A Describe the mode of action of recreational drugs and the effects on the body of their repeated use. OR B Describe the contents of vaccines and the design of cli... show full transcript
Worked Solution & Example Answer:A Describe the mode of action of recreational drugs and the effects on the body of their repeated use - Scottish Highers Human Biology - Question 15 - 2023
Step 1
Describe the mode of action of recreational drugs and the effects on the body of their repeated use.
Answer
Recreational drugs can act as:
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Agonists: These drugs stimulate receptors by mimicking the action of neurotransmitters. When an individual takes these drugs, they activate the reward pathways in the brain, leading to enhanced feelings of pleasure.
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Antagonists: In contrast, some recreational drugs can function as antagonists which block receptors. This can affect neurotransmission and result in various psychological effects such as mood alteration and perception changes.
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Addiction Mechanism: Addiction occurs due to repeated use of these drugs. The brain adjusts to the presence of the drug, often increasing the number or sensitivity of receptors, which can lead to craving behavior.
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Tolerance: Over time, individuals may develop tolerance to the drug, requiring larger doses to achieve the same effect. This is due to a decrease in receptor sensitivity or number in response to the continued presence of the substance.
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Withdrawal Effects: When an individual stops using the drug, they may experience withdrawal symptoms due to the brain's adjustment and lowered receptor activity.
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Long-term Effects: Prolonged use can lead to significant changes in brain function and structure, affecting cognitive functions, emotional regulation, and even leading to physical health problems.
Step 2
Describe the contents of vaccines and the design of clinical trials used to establish their effectiveness.
Answer
Vaccines are composed of:
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Antigens: These are derived from pathogens (which could be bacteria or viruses) and are essential for eliciting an immune response.
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Inactivated or Attenuated Pathogens: Some vaccines contain inactivated pathogens or weakened forms that can't cause disease but can still stimulate immunity.
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Adjuvants: These are included to enhance the immune response. They help create a more robust and longer-lasting immunity by boosting the body's reaction to the vaccine.
The design of clinical trials for vaccines includes several steps:
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Randomization: Participants are randomly assigned to different groups, which may include a vaccine group and a placebo group to ensure unbiased results.
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Controls and Placebo: These ensure that the effects of the vaccine can be appropriately compared against a group that does not receive the vaccine.
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Monitoring and Evaluation: The trials are designed to monitor the participants for any adverse reactions and to evaluate the vaccine's effectiveness statistically, using pre-set criteria to measure success.
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Size and Diversity: Trials must include a sufficiently large and diverse group of subjects to ensure that the results are generalizable across different populations.