which of the following neurotransmitters slows down the activity of the neurons preventing them from getting overexcited

ATI TEAS 7

ATI TEAS Practice Test Science

1. Which of the following neurotransmitters slows down the activity of neurons, preventing them from becoming overexcited?

A. Acetylcholine
B. Dopamine
C. GABA
D. Serotonin

Correct answer: C

Rationale: The correct answer is C: GABA (gamma-aminobutyric acid). GABA acts as an inhibitory neurotransmitter that reduces neuronal activity, thus preventing overexcitation. Acetylcholine (choice A) is involved in muscle control and cognitive function, but it is not primarily responsible for slowing down neuronal activity. Dopamine (choice B) plays a role in reward-motivated behavior and motor control, rather than inhibiting neuronal firing. Serotonin (choice D) is involved in mood regulation, sleep, and appetite but does not primarily slow down neuronal activity to prevent overexcitation.

2. A student hypothesizes that higher sugar consumption negatively impacts test scores. To investigate this, the student recruits participants to consume varying amounts of sugar, wait for one hour, and then complete an aptitude test. The student will record both the amount of sugar consumed and the test scores to analyze the relationship. What is the best experimental approach?

A. Conduct one round of testing where each participant consumes a different amount of sugar.
B. Conduct two rounds of testing: In the first round, participants consume varying amounts of sugar; in the second round, they consume the same amount of sugar as they did in the first round.
C. Conduct two rounds of testing: In the first round, participants consume varying amounts of sugar; in the second round, participants consume no sugar.
D. Conduct one round of testing where all participants consume the same amount of sugar.

Correct answer: C

Rationale: Option C provides the most thorough experimental design by including a control group. In the first round, varying sugar intake levels help explore the relationship between sugar consumption and test scores. In the second round, by having participants consume no sugar, the student can compare results to observe any changes due to sugar intake. This approach enhances the validity of the findings by accounting for potential confounding factors and better identifying causal relationships. Choice A is not ideal as it lacks a control group and does not compare the impact of sugar consumption. Choice B does not explore the effects of sugar consumption adequately as it does not include a group without sugar. Choice D does not allow for comparison between different sugar consumption levels, limiting the ability to draw meaningful conclusions.

3. Which human body system is correctly matched with its function?

A. Respiratory system; exchanges oxygen and carbon dioxide in the lungs.
B. Circulatory system; transports oxygen to cells and removes carbon dioxide.
C. Lymphatic system; produces antibodies that destroy virally affected or foreign cells.
D. Endocrine system; regulates hormones controlling bodily functions and metabolism.

Correct answer: B

Rationale: The circulatory system is responsible for the transportation of oxygen from the lungs to all the body's cells and tissues, as well as removing carbon dioxide from the cells and transporting it back to the lungs to be exhaled. This process is crucial for cellular respiration and the exchange of gases necessary for bodily functions. Choice B accurately matches the role of the circulatory system by describing its function of transporting oxygen to cells and removing carbon dioxide, which is essential for maintaining proper cellular activities. Choices A, C, and D are incorrect because they do not accurately match the body system with its function. The respiratory system primarily involves the exchange of gases in the lungs, not transportation to cells; the lymphatic system deals with immunity through the production of antibodies, not gas exchange; and the endocrine system's main function is hormone regulation, not the transport of gases.

4. Which of the following is an example of a nosocomial infection?

A. The common cold contracted from a family member
B. A urinary tract infection (UTI) acquired during a catheterization
C. A fungal skin infection from contaminated soil
D. Food poisoning from undercooked chicken

Correct answer: B

Rationale: A nosocomial infection, also known as a healthcare-associated infection (HAI), is an infection that is acquired in a healthcare setting. In this case, a UTI acquired during a catheterization procedure is a classic example of a nosocomial infection. Catheterization involves the insertion of a tube into the urinary tract, which can introduce bacteria into the urinary system and lead to an infection. Nosocomial infections are a significant concern in healthcare settings due to the potential for increased morbidity, mortality, and healthcare costs. Let's review the other options: A) The common cold contracted from a family member - This is not a nosocomial infection as it is acquired outside of a healthcare setting. C) A fungal skin infection from contaminated soil - This is not a nosocomial infection as it is acquired from environmental exposure, not in a healthcare setting.

5. What presents the correct order of cellular respiration?

A. Glycolysis, Acetyl-CoA, Citric Acid Cycle, Electron Transport Chain
B. Citric Acid Cycle, Glycolysis, Acetyl-CoA, Electron Transport Chain
C. Glycolysis, Acetyl-CoA, Electron Transport Chain, Citric Acid Cycle
D. Glycolysis, Citric Acid Cycle, Electron Transport Chain, Acetyl-CoA

Correct answer: A

Rationale: The correct order of cellular respiration is Glycolysis, Acetyl-CoA, Citric Acid Cycle, and Electron Transport Chain. Glycolysis initiates the breakdown of glucose in the cytoplasm, leading to the formation of pyruvate. This pyruvate is then converted to Acetyl-CoA in the mitochondria, which enters the Citric Acid Cycle to generate energy-rich molecules like NADH and FADH2. Finally, the Electron Transport Chain, located in the inner mitochondrial membrane, utilizes these energy carriers to produce ATP through oxidative phosphorylation. Choice B is incorrect because it starts with the Citric Acid Cycle, which comes after Glycolysis. Choice C is incorrect as it places the Citric Acid Cycle before the Electron Transport Chain. Choice D is incorrect by placing Acetyl-CoA last instead of before the Citric Acid Cycle.