which statement below correctly describes the movement of molecules in the body andor in relation to the external environment

ATI TEAS 7

ATI TEAS 7 Science Practice Test

1. Which statement below correctly describes the movement of molecules in the body and in relation to the external environment?

A. Osmosis is the movement of a solution from an area of low solute concentration to an area of high solute concentration.
B. Diffusion is the process in which oxygen moves from the lungs into the bloodstream.
C. Dissipation is the transport of molecules across a semipermeable membrane from low to high concentration.
D. Reverse osmosis is the movement of molecules in a solution from high concentration to low concentration.

Correct answer: B

Rationale: The correct answer is B. Diffusion is the process where molecules move from an area of higher concentration to an area of lower concentration. In the context of the lungs, oxygen moves from the alveoli in the lungs to the bloodstream through diffusion. Choice A is incorrect as osmosis involves the movement of water across a semipermeable membrane from an area of low solute concentration to an area of high solute concentration. Choice C is incorrect because dissipation does not refer to a specific biological process related to molecule movement. Choice D is incorrect as reverse osmosis is a process where solvent moves from an area of high solute concentration to an area of low solute concentration, not the movement of molecules within a solution.

2. Which type of bond is exemplified by KCl?

A. Ionic bond
B. Covalent bond
C. Hydrogen bond
D. Polar covalent bond

Correct answer: A

Rationale: KCl exemplifies an ionic bond. In an ionic bond, electrons are transferred between atoms, resulting in the formation of ions. In the case of KCl, potassium (K) donates an electron to chlorine (Cl), leading to the creation of K+ and Cl- ions, which are held together by electrostatic forces of attraction. Choice B, covalent bond, is incorrect because covalent bonds involve the sharing of electrons between atoms, not the transfer of electrons as seen in KCl. Choice C, hydrogen bond, is incorrect as hydrogen bonds are a type of intermolecular force, not a bond formed by the transfer or sharing of electrons between atoms. Choice D, polar covalent bond, is also incorrect because although it involves the sharing of electrons with an unequal distribution of charge, KCl is a clear example of ionic bonding where electrons are completely transferred.

3. Which part of the brain is responsible for regulating heart rate, breathing, and swallowing?

A. Cerebrum
B. Cerebellum
C. Medulla oblongata
D. Thalamus

Correct answer: C

Rationale: The correct answer is C, the medulla oblongata. This part of the brain, located at the base of the brainstem, is primarily responsible for regulating essential functions like heart rate, breathing, and swallowing. Choices A, B, and D are incorrect. The cerebrum is associated with higher brain functions such as thinking and voluntary movements, the cerebellum controls coordination and balance, and the thalamus serves as a relay station for sensory information. Therefore, the medulla oblongata specifically governs the autonomic functions critical for survival.

4. Diabetic nephropathy, a complication of diabetes, affects the:

A. Ureters
B. Bladder
C. Urethra
D. Nephrons

Correct answer: D

Rationale: Diabetic nephropathy, a complication of diabetes, affects the nephrons. Nephrons are the functional units of the kidneys responsible for filtering blood and producing urine. The high blood sugar levels associated with diabetes can damage the nephrons over time, leading to kidney dysfunction and, ultimately, kidney failure. Choices A, B, and C are incorrect because diabetic nephropathy primarily impacts the nephrons in the kidneys, not the ureters, bladder, or urethra.

5. What is the term for the ability of a substance to dissolve in another substance?

A. Solubility
B. Miscibility
C. Immiscibility
D. Reactivity

Correct answer: A

Rationale: Solubility is the property that describes the ability of a substance to dissolve in another substance. When a substance is soluble in another, it means it can form a homogeneous solution by dispersing at a molecular level within the solvent. Miscibility, on the other hand, refers to the ability of two liquids to mix and form a homogeneous solution. Immiscibility indicates the inability of substances to mix to form a homogeneous solution. Reactivity pertains to the ability of a substance to undergo chemical reactions, which is distinct from the concept of solubility.