which of the following describes a cells reaction to being placed in a hypertonic solution

ATI TEAS 7

TEAS 7 Science Practice Test

1. What describes a cell’s reaction to being placed in a hypertonic solution?

A. The cell will shrink as water is pulled out of the cell to equalize the concentrations inside and outside of the cell.
B. The cell will swell as water is pulled into the cell to equalize the concentrations inside and outside of the cell.
C. The cell will remain the same size since the concentrations inside and outside the cell are equal to begin with.
D. The pH inside the cell will drop in order to equalize the pH inside and outside the cell.

Correct answer: A

Rationale: A cell placed in a hypertonic solution has a higher solute concentration outside the cell compared to inside. This creates a concentration gradient that causes water to move out of the cell through osmosis to equalize the concentrations on both sides. As a result, the cell will shrink or undergo plasmolysis, as water is pulled out of the cell. Choice B is incorrect because a hypertonic solution causes water to move out of the cell, leading to shrinkage rather than swelling. Choice C is incorrect as a hypertonic solution results in a concentration gradient that leads to water leaving the cell, causing it to shrink. Choice D is incorrect because pH is not directly affected by being placed in a hypertonic solution; the change in solute concentration primarily impacts water movement.

2. Which of the following is NOT a recognized mode of natural selection?

A. Directional selection (favoring one extreme trait value on a spectrum)
B. Disruptive selection (favoring both extreme trait values on a spectrum)
C. Stabilizing selection (favoring the average trait value on a spectrum)
D. Sexual selection (selection based on mate choice that influences reproductive success)

Correct answer: D

Rationale: A) Directional selection is a recognized mode of natural selection where one extreme trait value on a spectrum is favored over others, leading to a shift in the average trait value over time. B) Disruptive selection is a recognized mode of natural selection where both extreme trait values on a spectrum are favored over the average trait value, potentially causing the population to split into distinct groups. C) Stabilizing selection is a recognized mode of natural selection favoring the average trait value on a spectrum over extreme values, resulting in reduced genetic diversity. D) Sexual selection differs from traditional natural selection modes as it involves mate choice and competition for mates, not direct selection pressure on traits affecting survival and reproduction in the environment. Sexual selection can drive the evolution of traits enhancing an individual's attractiveness for mating purposes.

3. Which structure protects the lungs?

A. Femur
B. Ribcage
C. Scapula
D. Skull

Correct answer: B

Rationale: The ribcage is the correct answer. It protects the lungs by providing structural support and shielding them from injury. The femur is a bone in the thigh and does not protect the lungs. The scapula is a shoulder blade bone, and the skull protects the brain, not the lungs.

4. Where does mRNA translation typically occur?

A. On the ribosome
B. In the nucleus
C. In the cytoplasm
D. On the smooth endoplasmic reticulum

Correct answer: A

Rationale: mRNA translation typically occurs on the ribosome. Ribosomes are the cellular machinery responsible for protein synthesis. They read the mRNA sequence and assemble amino acids into a polypeptide chain during translation. The correct answer is A. Choices B, C, and D are incorrect. The nucleus is where mRNA is transcribed from DNA, while translation occurs in the cytoplasm on ribosomes. The smooth endoplasmic reticulum is involved in protein processing and transport but not in mRNA translation.

5. The pancreas secretes digestive enzymes into the small intestine. What enzyme breaks down proteins into amino acids?

A. Pepsin
B. Lipase
C. Amylase
D. Trypsin

Correct answer: D

Rationale: Trypsin is the correct enzyme that breaks down proteins into amino acids. It is produced by the pancreas and released into the small intestine to facilitate protein digestion. Pepsin is an enzyme from the stomach that also breaks down proteins, amylase targets carbohydrates, and lipase works on fats. In this context, since the question specifies the pancreas and small intestine, the correct answer is Trypsin as it is the pancreatic enzyme responsible for protein breakdown in the small intestine.