when animals eat insulin is released from the pancreas stimulating glucose uptake by the liver when glucose levels drop the pancreas reduces insulin r

ATI TEAS 7

ATI TEAS Science Test

1. When animals eat, insulin is released from the pancreas, stimulating glucose uptake by the liver. When glucose levels drop, the pancreas reduces insulin release. This is an example of which mechanism for maintaining homeostasis?

A. Negative feedback.
B. Positive feedback.
C. Stress response.
D. Parasympathetic regulation.

Correct answer: A

Rationale: This mechanism is an example of negative feedback. Negative feedback systems work to counteract changes in the body and maintain a stable internal environment (homeostasis). In this case, the release of insulin in response to high glucose levels is followed by a reduction in insulin release when glucose levels drop. This response helps regulate glucose levels and return them to a normal range, demonstrating the characteristic of negative feedback where the body's response opposes the initial stimulus to maintain equilibrium. Positive feedback would amplify the initial change rather than counteract it, so it is not the correct choice. Stress response and parasympathetic regulation are not directly involved in this glucose regulation process, making them incorrect choices.

2. Which of the following statements is NOT true about DNA?

A. DNA contains the nucleotides A, T, C, G and is read 5' to 3'.
B. DNA contains genetic information and is tightly coiled with proteins to form chromosomes.
C. DNA contains the nucleotides A, T, C, G and is read 3' to 5'.
D. DNA is a double-stranded molecule connected by hydrogen bonds.

Correct answer: C

Rationale: The correct answer is C because DNA is typically read from the 5' end to the 3' end, not from 3' to 5'. Choices A, B, and D are all true statements about DNA. DNA contains the nucleotides A, T, C, G and is read in a 5' to 3' direction. DNA also contains genetic information and is tightly coiled with proteins to form chromosomes. Additionally, DNA is a double-stranded molecule connected by hydrogen bonds.

3. Which of the following organs is responsible for producing digestive enzymes?

A. Liver
B. Pancreas
C. Gallbladder
D. Esophagus

Correct answer: B

Rationale: The correct answer is the Pancreas. The pancreas is an organ that produces digestive enzymes to aid in the breakdown of food in the small intestine. These enzymes play a crucial role in the digestion and absorption of nutrients from the food we eat. The liver is responsible for producing bile, not digestive enzymes. The gallbladder stores and concentrates bile produced by the liver, which aids in the digestion of fats. The esophagus is a muscular tube that helps in the movement of food from the mouth to the stomach and does not produce digestive enzymes.

4. In the suburban neighborhood of Northwoods, there has been a large population of deer, and residents have complained about them eating flowers and garden plants. What would be a logical explanation for the large increase in the deer population over the last two seasons?

A. There has been an increase in the quantity of food sources in surrounding areas.
B. The population of natural predators in Northwoods has decreased.
C. Deer have migrated from surrounding areas.
D. There has been a recent increase in hunting licenses sold.

Correct answer: B

Rationale: The correct answer is B because a decrease in natural predators can lead to an increase in the deer population as there are fewer predators to control their numbers. This explanation aligns with the situation described in the question, where the deer population has increased, causing issues for residents. Choice A is incorrect because an increase in food sources would not directly explain the increase in the deer population. Choice C is incorrect as it introduces a new factor of migration which is not mentioned in the question. Choice D is incorrect as an increase in hunting licenses sold would likely have the opposite effect on the deer population.

5. Isotopes are variants of a single element that differ in:

A. Having the same number of protons but varying numbers of neutrons
B. Having the same number of neutrons but varying numbers of protons
C. Having the same mass but different atomic numbers
D. None of the above

Correct answer: A

Rationale: Isotopes are variants of a single element that have the same number of protons, the defining characteristic of an element. They differ in the number of neutrons they possess, leading to isotopes having different atomic masses while retaining the same chemical properties. Choice B is incorrect because isotopes have the same number of neutrons and differ in the number of protons. Choice C is incorrect because isotopes have different masses due to varying numbers of neutrons, not different atomic numbers. Choice D is incorrect as isotopes do differ in the number of neutrons they possess.