ATI TEAS 7
ATI TEAS 7 Version 1 Science Questions
Extract:
Question 1 of 5
If a portion of a strand of DNA bases reads 5' AGCTAGCGT 3', what would the sequence of bases on the complementary strand read?
Correct Answer: C
Rationale: To determine the sequence of bases on the complementary DNA strand, you must apply the base pairing rules: adenine (A) pairs with thymine (T) and cytosine (C) pairs with guanine (G). The given original sequence is 5' AGCTAGCGT 3'. Consequently, the complementary strand will read 3' TCGATCGCA 5'. Each base on one strand corresponds with its complementary base on the other strand, forming a sequence that complements the original one.
Question 2 of 5
Which of the following are the major parts of the nervous system?
Correct Answer: C
Rationale: The nervous system comprises two major parts: the peripheral nervous system (PNS) and the central nervous system (CNS). The PNS includes nerves outside the brain and spinal cord, while the CNS consists of the brain and spinal cord. Choice C (PNS and CNS) correctly identifies the primary divisions of the nervous system, encompassing both the peripheral and central components. Therefore, the correct answer is C.
Question 3 of 5
Which of the following substances is responsible for donating H+ ions to act as a buffer when blood pH rises?
Correct Answer: D
Rationale: Carbonic acid is a pivotal buffer in blood that plays a key role in maintaining pH balance. When blood pH rises, indicating increased alkalinity, carbonic acid releases hydrogen ions (H+) to counterbalance the excess base, thereby preventing significant changes in pH levels. This mechanism highlights the essential function of carbonic acid in regulating the acid-base equilibrium in the blood.
Question 4 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.
Question 5 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.