ATI TEAS Science Practice Test

Correct Answer: A

Rationale: The sternum is located at the midline of the body, closer to the center, making it medial to the deltoid. The deltoid muscle is positioned on the lateral side of the upper arm, away from the midline. Therefore, the correct relationship of the sternum to the deltoid is medial. 'Lateral' is incorrect as it refers to a position farther away from the midline, 'Superficial' is incorrect as it relates to a structure being closer to the surface, and 'Posterior' is incorrect as it indicates a position behind or toward the back.

Correct Answer: C

Rationale: The correct answer is C: Double-stranded, helix. DNA is structured as a double helix formed by two strands of nucleotides. The nucleotides are paired with complementary bases (A-T and C-G) in the center, held together by hydrogen bonds. This double-stranded helical structure is a fundamental characteristic of DNA and essential for its function in storing genetic information. Choices A, B, and D are incorrect because DNA is not single-stranded; it consists of two strands that run antiparallel to each other and are connected via hydrogen bonds. Additionally, DNA does not have a linear structure but rather a helical one, providing stability and protection to the genetic information it carries.

Correct Answer: C

Rationale: The correct answer is C: Connective tissue. The dermis is primarily composed of connective tissue, which includes collagen and elastin fibers that provide strength and elasticity to the skin. It houses blood vessels, nerve endings, hair follicles, and glands, playing a crucial role in supporting the skin structure and function. Adipose tissue (choice A) is found in the subcutaneous layer beneath the dermis, providing insulation and energy storage. Epithelial cells (choice B) form the outermost layer of the skin called the epidermis. Muscle tissue (choice D) is not a significant component of the dermis but is found deeper in the body associated with movement and support.

Correct Answer: C

Rationale: The correct answer is C. Systemic circulation is longer as it involves carrying oxygenated blood throughout the body, requiring higher blood pressure. Pulmonary circulation is shorter and involves the flow of blood only through the lungs, hence having lower blood pressure. Therefore, systemic circulation is longer and has higher blood pressure compared to pulmonary circulation. Choice A is incorrect as systemic circulation is longer, not shorter, and has higher blood pressure. Choice B is incorrect as pulmonary circulation has lower blood pressure, not higher. Choice D is incorrect as systemic circulation is longer, not shorter, despite having higher blood pressure.

Correct Answer: C

Rationale: The correct answer is C: 'Bonding electrons are shared between two or more atoms.' This statement is unique to covalent bonds. In covalent bonds, atoms share electrons to achieve a stable electron configuration, which leads to the formation of a bond. This sharing of electrons is a fundamental characteristic of covalent bonds and distinguishes them from other types of chemical bonds, such as ionic bonds, where electrons are transferred rather than shared. Choices A, B, and D do not represent unique characteristics of covalent bonds. Choice A describes some common elements involved in covalent bonds, choice B refers to the concept of dipoles, which can also exist in other types of bonds, and choice D describes a property of molecules (crystalline solid structure) that is not exclusive to covalent bonds.