what is the role of rna in protein synthesis

ATI TEAS 7

TEAS version 7 quizlet science

1. What is the role of RNA in protein synthesis?

A. Stores genetic information
B. Decodes genetic information
C. Provides energy for the process
D. Transports amino acids to the ribosomes

Correct answer: B

Rationale: RNA plays a crucial role in protein synthesis by decoding the genetic information stored in DNA and carrying it to the ribosomes where proteins are synthesized. This process involves transcription, where RNA is synthesized from DNA, and translation, where the information in RNA is used to assemble amino acids into proteins. RNA acts as a messenger between DNA and the ribosomes, ensuring that the correct sequence of amino acids is used to build proteins according to the genetic code. Option A is incorrect because DNA, not RNA, stores genetic information. Option C is incorrect because RNA does not provide energy for protein synthesis; energy is usually provided by ATP molecules. Option D is incorrect because tRNA (transfer RNA) is responsible for transporting amino acids to the ribosomes, not RNA in general. Therefore, option B is the most appropriate choice as it accurately describes the role of RNA in protein synthesis.

2. What is the function of valves in arteries?

A. To maintain high blood pressure for the proper diffusion of nutrients in capillaries.
B. To prevent backflow of blood due to high pressure away from the heart.
C. As a vestigial trait from evolution, like the appendix, that serves no purpose.
D. Valves are absent in arteries but present in veins.

Correct answer: B

Rationale: Valves in arteries serve the crucial function of preventing backflow of blood. Arteries carry blood at high pressure away from the heart, and the valves ensure that blood flows in one direction, towards the capillaries, to maintain efficient circulation. Without these valves, there would be a risk of blood flowing backward, compromising the effectiveness of blood circulation in the body. Choices A, C, and D are incorrect. Choice A incorrectly suggests that valves maintain high blood pressure for nutrient diffusion in capillaries, which is not their function. Choice C inaccurately compares valves to vestigial traits, like the appendix, implying they serve no purpose, which is untrue. Choice D is incorrect as valves are indeed present in arteries to regulate blood flow, not just in veins.

3. What type of vessel carries oxygen-rich blood from the heart to other tissues of the body?

A. Veins
B. Intestines
C. Bronchioles
D. Arteries

Correct answer: D

Rationale: The correct answer is D: Arteries. Arteries are blood vessels that carry oxygen-rich blood away from the heart to supply oxygen to the tissues and organs throughout the body. Veins, choice A, carry oxygen-poor blood back to the heart, not oxygen-rich blood. Intestines, choice B, are part of the digestive system and do not play a role in carrying blood. Bronchioles, choice C, are small air passages in the lungs responsible for carrying air, not blood.

4. What impact would the removal of a keystone species have in an ecosystem?

A. Lead to a decrease in competition among other species
B. Cause a slight increase in primary productivity
C. Have a minimal impact on the overall ecosystem structure
D. Disrupt the food web and cause cascading effects on other populations

Correct answer: D

Rationale: Keystone species play a crucial role in maintaining the balance and structure of an ecosystem due to their significant influence. If a keystone species is removed, it disrupts the delicate food web dynamics and can trigger cascading effects throughout the ecosystem. The disruption in predator-prey relationships can lead to population declines and even extinctions of other species. Options A, B, and C are incorrect because the removal of a keystone species would not decrease competition among other species, cause a slight increase in primary productivity, or have a minimal impact on the overall ecosystem structure. Instead, it would have a profound impact, disrupting the food web and causing cascading effects on other populations.

5. The hypothalamus, a part of the brain, plays a crucial role in endocrine regulation. It secretes GnRH (Gonadotropin-releasing hormone) which stimulates the pituitary gland to produce FSH and LH. What is the MAIN function of FSH and LH?

A. Regulate blood sugar levels
B. Control growth and development
C. Stimulate the fight-or-flight response
D. Maintain calcium homeostasis

Correct answer: B

Rationale: FSH (Follicle-stimulating hormone) and LH (Luteinizing hormone) are hormones produced by the pituitary gland in response to GnRH from the hypothalamus. FSH plays a key role in the growth and development of ovarian follicles in females and sperm production in males. LH is essential for the maturation of the ovarian follicle, ovulation, and the formation of the corpus luteum in females, as well as the production of testosterone in males. Therefore, the main function of FSH and LH is to control growth and development in the reproductive system. Choices A, C, and D are incorrect as they do not align with the roles of FSH and LH in reproductive physiology. Regulating blood sugar levels is primarily the function of insulin and glucagon, controlling the fight-or-flight response involves hormones like adrenaline and noradrenaline, and maintaining calcium homeostasis is mainly regulated by parathyroid hormone and calcitonin.