AQA Module B1 Biology (Drugs)

Nicotine is the correct answer because it is the addictive drug found in cigarette smoke. It stimulates the release of dopamine in the brain, creating a pleasurable sensation and leading to addiction. Tar and carbon monoxide are harmful substances found in cigarette smoke, but they are not the addictive components. Smoke is a byproduct of burning tobacco and contains various harmful chemicals, but it is not the addictive drug itself.

The correct answer is that the drug contains a chemical. This is because addiction is primarily caused by the chemical composition of the drug. Certain substances, such as opioids or stimulants, can alter the brain's chemistry and create a physical and psychological dependence. The presence of addictive chemicals in the drug can lead to cravings, tolerance, and withdrawal symptoms, ultimately leading to addiction. The ease of swallowing, legality, or availability of the drug may play a role in initial exposure or accessibility, but they are not the primary factors that contribute to addiction.

A placebo refers to a fake drug that is utilized in clinical trials to assess the effectiveness of a new treatment. It is designed to resemble the actual medication but does not contain any active ingredients. Placebos are given to a control group to compare the effects of the real drug against the effects of a non-active substance. This helps researchers determine the true impact of the medication being tested by differentiating it from the psychological and subjective effects that can occur due to the placebo effect.

Carbon monoxide is a toxic gas that can be harmful to both the mother and the developing fetus. When inhaled, carbon monoxide binds to the hemoglobin in the blood, reducing its ability to carry oxygen to the fetus. This lack of oxygen can result in slow growth of the fetus as it does not receive sufficient nutrients and oxygen for proper development. Therefore, exposure to carbon monoxide during pregnancy can have detrimental effects on the growth and development of the fetus.

The correct answer is "taken for pleasure" because recreational drugs are substances that are used solely for their pleasurable effects, rather than for any medicinal or therapeutic purposes. These drugs are typically used to enhance mood, induce euphoria, or alter perception, and are not intended for treating any specific medical condition. They are often used recreationally in social settings or for personal enjoyment, rather than for any specific health benefit.

A gateway drug refers to a substance that, while not inherently dangerous or illegal, can potentially lead an individual to experiment with or develop a dependency on more harmful and addictive drugs. This answer suggests that a gateway drug has the potential to lead individuals towards using harder drugs, which are typically more dangerous and illegal.

In this investigation, the reaction time is being measured, which is a continuous variable. Continuous variables can take on any value within a certain range and can be measured with precision. In the case of reaction time, it can vary from very short durations to longer durations, making it a continuous variable.

Emphysema is a disease caused by smoking that primarily affects the lungs. It is a chronic lung condition characterized by the damage and enlargement of the air sacs in the lungs, leading to difficulty in breathing. Smoking causes inflammation and destruction of the lung tissue, resulting in the loss of elasticity and impaired lung function. This condition is not related to the throat, heart, or liver, but specifically affects the lungs.

Tar is the correct answer because it is a known carcinogenic substance found in cigarette smoke. When tobacco is burned, tar is produced and it contains various harmful chemicals, including carcinogens. These carcinogens can cause damage to the DNA in our cells, leading to the development of cancer over time. Tar also contributes to the buildup of plaque in the lungs, which can lead to respiratory problems and diseases. Therefore, it is important to understand the harmful effects of tar in cigarette smoke and the associated health risks.

In this investigation, the dependent variable refers to the variable that is being measured or observed to determine the effect of caffeine on human reaction time. The reaction time is the variable that is being measured in this study to determine if and how caffeine affects it. The presence or absence of caffeine, the volume of drink consumed, and the time between drinking and measuring reaction time are all independent variables that may be manipulated or controlled in the study to see their impact on the dependent variable, which is the reaction time.

A healthy liver takes approximately 60 minutes to breakdown one unit of alcohol. The liver is responsible for metabolizing alcohol, and it does so at a fairly consistent rate. One unit of alcohol is equivalent to 10 milliliters or 8 grams of pure alcohol. This means that it takes about an hour for the liver to process and eliminate this amount of alcohol from the body. It's important to note that this rate may vary depending on factors such as body weight, metabolism, and overall health.

Cirrhosis and Liver Cancer are both diseases that can be caused by excessive alcohol consumption. Cirrhosis is a condition where the liver becomes scarred and damaged, leading to liver dysfunction. Alcohol is a major cause of cirrhosis. Liver Cancer, on the other hand, is a type of cancer that can develop in the liver, and excessive alcohol consumption is a known risk factor for its development. Both of these diseases are serious and can have significant health consequences for individuals who consume alcohol excessively.

The presence or absence of caffeine in this investigation is a categoric variable because it can only take on two distinct categories: either the participant has consumed caffeine or they have not.

The best conclusion from the finding is that caffeine increases reaction time by 0.25s. This is because the decaffeinated drink increased reaction time by 0.5s, while the same volume of caffeinated drink increased it by 0.75s. By comparing these two results, we can infer that the additional 0.25s increase in reaction time is specifically caused by the presence of caffeine in the drink.

In this investigation, the independent variable is the presence or absence of caffeine. This means that the researchers are manipulating whether or not the participants are exposed to caffeine. The purpose of this manipulation is to determine how caffeine affects human reaction time. By comparing the reaction times of participants who consume caffeine with those who do not, the researchers can determine the effect of caffeine on reaction time. The other options listed, such as the reaction time itself, the volume of drink consumed, and the time between drinking and measuring reaction time, are not the independent variable because they are not being manipulated by the researchers.

A bar chart with caffeine on the X axis would be the best type of chart to summarize the results of the investigation. This is because the investigation is specifically looking at the effect of the presence or absence of caffeine on human reaction time. By using a bar chart with caffeine on the X axis, we can easily compare and visualize the reaction time for each condition (presence or absence of caffeine). The bars can represent the average reaction time for each condition, allowing for a clear comparison between the two.

An illegal drug refers to a substance that is prohibited by law and its possession, use, or distribution is considered a criminal offense. Caffeine and alcohol are legal substances that can be purchased and consumed by individuals without a prescription. Therefore, they cannot be classified as illegal drugs. On the other hand, a drug that is available on prescription means that it can only be obtained under the supervision and authorization of a healthcare professional. Hence, the correct answer is "not available on prescription."