ATI TEAS 7
ATI TEAS 7 Version 1 Science Questions
Extract:
Question 1 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.
Extract:
Question 2 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 3 of 5
What causes osteoporosis?
Correct Answer: B
Rationale: Osteoporosis is a condition characterized by reduced bone density and mass, leading to brittle bones. Osteoblasts are cells responsible for forming new bone tissue, while osteoclasts break down old or damaged bone. In osteoporosis, there is a decrease in osteoblast activity, causing a net loss of bone as the breakdown surpasses formation. Meanwhile, osteoclast activity remains relatively stable. This imbalance between bone formation (osteoblast activity) and bone resorption (osteoclast activity) contributes to the development of osteoporosis by reducing bone strength and increasing susceptibility to fractures.
Question 4 of 5
In a phase diagram, what term is used for a substance held at a temperature and pressure where solid, liquid, and gaseous states of a substance exist simultaneously?
Correct Answer: B
Rationale: The point described in the question is called the triple point. At the triple point, all three phases of a substance (solid, liquid, and gas) coexist in equilibrium. The critical temperature is the highest temperature at which a distinct liquid phase can form, while absolute zero is the lowest possible temperature. The critical point is the point on a phase diagram that represents the highest temperature and pressure at which a distinct liquid and gas phase can coexist. Therefore, the correct answer is the triple point, where all three phases coexist.
Extract:
Question 5 of 5
Which of the following cells secrete bone material?
Correct Answer: D
Rationale: Osteocytes are the cells responsible for maintaining bone tissue and secreting bone material, contributing to the overall structure and strength of bones.