ATI TEAS 7
ATI TEAS 7 Version 1 Science Questions
Extract:
Question 1 of 5
Which substance protects the body from ultraviolet rays?
Correct Answer: D
Rationale: Melanin is the pigment responsible for skin color and serves as a natural defense against ultraviolet (UV) rays. When the skin is exposed to UV rays, melanin production increases to absorb and dissipate the radiation, acting as a protective mechanism. This helps prevent DNA damage, reducing the risk of skin cancer and other UV-induced skin issues. Therefore, melanin is the substance that effectively shields the body from the harmful effects of UV radiation.
Extract:
Question 2 of 5
Which of the following substances is excreted by the sweat glands in response to the breakdown of proteins and the formation of ammonia?
Correct Answer: C
Rationale: The correct answer is Urea. Sweat glands excrete urea in response to the breakdown of proteins and the formation of ammonia. Urea is a waste product formed in the liver by the breakdown of amino acids. It is then excreted by the kidneys in urine and by sweat glands through perspiration. Urea plays a vital role in the excretory process by helping eliminate nitrogenous wastes from the body and maintaining proper physiological balance.
Question 3 of 5
Which of the following properties of water explains its solvent abilities for certain substances?
Correct Answer: B
Rationale: The correct answer is B: Polarity. Water's polarity, resulting from its unequal sharing of electrons and the formation of hydrogen bonds, makes it an excellent solvent. The polar nature of water allows it to interact with and dissolve substances that have charges or partial charges, aiding in their breakdown at a molecular level. Choices A, C, and D are not directly associated with water's solvent capabilities. High specific heat (Choice A) refers to water's ability to resist temperature changes, volume (Choice C) is the amount of space occupied by water, and high surface tension (Choice D) pertains to water's cohesive properties.
Question 4 of 5
After infecting host cells, how does the AIDS virus, which contains RNA, insert viral DNA into the host T-cell?
Correct Answer: B
Rationale: Reverse transcriptase is an essential enzyme unique to retroviruses like the AIDS virus. It catalyzes the conversion of viral RNA into DNA through a process known as reverse transcription. The newly formed viral DNA is then integrated into the host cell's genome, enabling the virus to replicate and establish a persistent infection within the host.
Question 5 of 5
What summarizes a change that occurs as solids transition into liquids?
Correct Answer: A
Rationale: The correct answer is A. When solids transition into liquids, particles become less ordered. In a solid state, particles are arranged in a fixed, orderly pattern due to strong intermolecular forces. As the solid transitions into a liquid, these forces weaken, allowing the particles more freedom of movement. Consequently, the particles become less ordered in a liquid compared to a solid, where they have more mobility and are not bound in a fixed structure.