the measurable electrical activity of the brain is recorded by a

ATI TEAS 7

ati teas 7 science

1. Which of the following is used to record the measurable electrical activity of the brain?

A. CAT scan
B. MRI scan
C. Electroencephalogram (EEG)
D. X-ray

Correct answer: C

Rationale: The correct answer is an Electroencephalogram (EEG). An EEG is specifically designed to record the measurable electrical activity of the brain. It does so by using small, flat metal discs (electrodes) attached to the scalp to detect brain activity. This test is crucial in diagnosing various conditions like seizures, epilepsy, head injuries, dizziness, headaches, and brain tumors. The other options, CAT scan, MRI scan, and X-ray, are imaging techniques that do not directly measure the brain's electrical activity. CAT scan and MRI scan provide detailed images of the brain's structure, while X-ray is more suited for visualizing bone structures or dense tissues.

2. Which hormone, produced by the adrenal glands, helps regulate the body's response to stress, including increasing blood pressure and suppressing the immune system?

A. Aldosterone
B. Epinephrine
C. Cortisol
D. Insulin

Correct answer: C

Rationale: Cortisol is the correct answer. It is the hormone produced by the adrenal glands that helps regulate the body's response to stress. Cortisol plays a crucial role in increasing blood pressure and suppressing the immune system during stressful situations. Aldosterone, another hormone from the adrenal glands, primarily regulates salt and water balance in the body, not the stress response. Epinephrine, also known as adrenaline, is produced by the adrenal glands in response to stress, but its effects are more immediate and short-lived compared to cortisol. Insulin, produced by the pancreas, regulates blood sugar levels and is not directly involved in the body's response to stress.

3. Which term is used interchangeably with negative variation?

A. Non-correlation
B. Direct correlation
C. Inverse correlation
D. Positive correlation

Correct answer: C

Rationale: The correct answer is C: Inverse correlation. Negative variation is synonymous with inverse correlation, indicating that as one variable increases, the other decreases. This relationship is the opposite of positive correlation, where both variables increase or decrease together. Non-correlation and direct correlation do not convey the concept of negative variation and are not interchangeable terms in this context. Non-correlation refers to variables that are not related or associated, while direct correlation indicates that as one variable increases, the other also increases. Positive correlation describes a relationship where both variables increase together, which is the opposite of negative variation.

4. When ethanol (C₂H₅OH) reacts with sodium metal (Na), what is the product?

A. Ethene (C₂H₄)
B. Sodium ethoxide (C₂H₅ONa)
C. Ethane (C₂H₆)
D. Sodium acetate (CH₃COONa)

Correct answer: B

Rationale: When ethanol (C₂H₅OH) reacts with sodium metal (Na), the product formed is Sodium ethoxide (C₂H₅ONa). This reaction is a classic example of a metal displacing hydrogen in an alcohol to form an alkoxide. In this specific case, sodium replaces the hydrogen in ethanol, resulting in the formation of sodium ethoxide. Choice A, Ethene (C₂H₄), is incorrect as it is a different compound formed from the dehydration of ethanol, not its reaction with sodium. Choice C, Ethane (C₂H₆), is incorrect as it is a saturated hydrocarbon, not the product of the reaction of ethanol with sodium metal. Choice D, Sodium acetate (CH₃COONa), is incorrect as it involves acetic acid, not ethanol, reacting with sodium to form the salt sodium acetate.

5. Which of the following correctly orders the layers of the epidermis from most superficial to deepest?

A. S. spinosum, S. basale, S. corneum, S. granulosum, S. lucidum
B. S. corneum, S. lucidum, S. granulosum, S. spinosum, S. basale
C. S. corneum, S. spinosum, S. basale, S. granulosum, S. lucidum
D. S. basale, S. spinosum, S. granulosum, S. lucidum, S. corneum

Correct answer: B

Rationale: The correct order of the layers of the epidermis from most superficial to deepest is: Stratum corneum, Stratum lucidum, Stratum granulosum, Stratum spinosum, Stratum basale. Choice B, 'S. corneum, S. lucidum, S. granulosum, S. spinosum, S. basale,' provides the accurate layering from the outermost to the innermost layer of the epidermis. Choice A is incorrect as it starts with Stratum spinosum, which is not the most superficial layer. Choice C is incorrect as it places Stratum spinosum before Stratum basale. Choice D is incorrect as it starts with Stratum basale, which is the deepest layer of the epidermis.