which of the following nucleic acids carries amino acids to organelles called ribosomes in which the amino acids are linked one by one to produce a po

ATI TEAS 7

ATI TEAS 7 Science

1. Which of the following nucleic acids carries amino acids to organelles called ribosomes, where the amino acids are linked one by one to produce a polypeptide?

A. DNA
B. mRNA
C. rRNA
D. tRNA

Correct answer: D

Rationale: tRNA is the correct answer as it carries amino acids to the ribosomes during protein synthesis. Transfer RNA (tRNA) plays a crucial role in protein synthesis by bringing specific amino acids to the ribosome according to the mRNA sequence. Once at the ribosome, the amino acids are linked together to form a polypeptide chain. This process is essential for the creation of proteins in the cell, highlighting the significance of tRNA in the translation process. Choice A, DNA, is incorrect as DNA does not directly participate in protein synthesis. Choice B, mRNA, is incorrect as mRNA carries the genetic information from DNA to the ribosome but does not directly carry amino acids. Choice C, rRNA, is incorrect as ribosomal RNA is a component of the ribosome structure and is involved in protein synthesis but does not carry amino acids like tRNA.

2. How does the body maintain a relatively constant blood pH level, even with changes in blood carbon dioxide concentration?

A. Cellular respiration
B. Gas exchange
C. Buffering system
D. Deoxygenation

Correct answer: C

Rationale: The correct answer is C: Buffering system. The buffering system is responsible for maintaining a relatively constant blood pH level by minimizing changes in pH when acids or bases are added to the blood. This system consists of chemical compounds that can donate or accept protons to help stabilize the pH. Choice A, Cellular respiration, and Choice B, Gas exchange, are processes involved in gas exchange within the body, not specifically related to maintaining blood pH. Choice D, Deoxygenation, refers to the removal of oxygen from a substance and is not directly related to the regulation of blood pH.

3. What is the primary function of Bartholin's glands?

A. Secretes hormones that help the body respond to stress
B. Provide lubrication for the vagina
C. Helps control growth and development of the body
D. Stimulate the development of T cells

Correct answer: B

Rationale: Bartholin's glands are two small glands located on each side of the vaginal opening. Their primary function is to secrete fluids that help lubricate the vagina during sexual arousal. This lubrication helps to reduce friction and discomfort during sexual activity, making intercourse more comfortable and pleasurable. Choices A, C, and D are incorrect because Bartholin's glands do not secrete hormones to respond to stress, control growth and development, or stimulate the development of T cells. Their main role is specifically related to vaginal lubrication.

4. 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.

5. Which of the following is a special property of water?

A. Water does not easily flow through phospholipid bilayers.
B. A water molecule's oxygen atom does not allow fish to breathe.
C. Water is highly cohesive, which explains its high melting point.
D. Water cannot self-hydrolyze and decompose into hydrogen and oxygen.

Correct answer: C

Rationale: Water is highly cohesive, meaning it is attracted to itself due to its hydrogen bonding properties. This cohesion is the reason why water has a high melting point compared to other liquids of similar molecular weight. It is crucial for the existence of life on Earth as it allows water to remain a liquid within a wide range of temperatures, providing a stable environment for biological processes to occur. Choices A, B, and D are incorrect. Water's cohesive property does not directly relate to its ability to flow through phospholipid bilayers, assist fish in breathing, or self-hydrolyze into hydrogen and oxygen.