Mometrix TEAS 7 science practice test

Correct Answer: A

Rationale: The relationship between wavelength (λ), frequency (f), and speed (v) of a wave is given by the formula λ = v / f. This formula is derived from the wave equation v = fλ, where v is the speed of the wave, f is the frequency, and λ is the wavelength. By rearranging the equation, we get λ = v / f, indicating that the wavelength is inversely proportional to the frequency when the speed of the wave is constant. Therefore, choice A, λ = v / f, correctly represents the relationship between wavelength and frequency when the speed of the wave is held constant. Choice B, λ = f / v, is incorrect because it represents an inverse relationship between wavelength and speed, which is not the case. Choice C, λ = vf, is incorrect as it implies a direct relationship between wavelength, frequency, and speed, which is not accurate. Choice D, λ is independent of f and v, is incorrect as both frequency and speed affect the wavelength of a wave, as shown by the correct formula λ = v / f.

Correct Answer: D

Rationale: Among the choices provided, carbon, in the form of diamond, has the highest melting point of any element. Diamond's strong covalent bonds between carbon atoms make it incredibly resistant to heat and pressure, giving it the highest melting point compared to tungsten, iron, and platinum. Tungsten is known for its high melting point among metals but not as high as carbon. Iron and platinum have lower melting points compared to carbon, making them incorrect choices in this context.

Correct Answer: A

Rationale: The correct answer is the centromere. It is the structure that attaches to each chromosome during mitosis. The centromere serves as the attachment point for spindle fibers during cell division, ensuring proper distribution of chromosomes to daughter cells. Telomeres are found at the ends of chromosomes, providing protection and stability. The spindle apparatus is responsible for separating chromosomes during cell division. The nucleolus, located within the nucleus, is involved in ribosomal RNA synthesis and not in chromosome attachment during mitosis.

Correct Answer: B

Rationale: The atomic number of an element represents the number of protons in the nucleus of an atom. This number determines the element's unique identity and its position on the periodic table. The atomic mass (option A) is not directly determined by the atomic number but is a weighted average of the isotopes of an element. The number of neutrons (option C) is not directly provided by the atomic number but can be calculated by subtracting the atomic number from the atomic mass. The position on the periodic table (option B) is directly related to the atomic number, as elements are arranged in order of increasing atomic number. The chemical properties of an element (option D) are influenced by the number of protons in the nucleus, which is determined by the atomic number.

Correct Answer: B

Rationale: Chromium is the correct answer. Chromium is the element used in insulin that aids in its function by enhancing glucose uptake into cells and regulating blood sugar levels. It plays a crucial role in the body's energy production processes by facilitating the action of insulin. Zinc (Choice A), although important for various physiological functions, is not the element used in insulin. Manganese (Choice C) is necessary for enzyme activation but is not directly involved in insulin's function. Iron (Choice D) is essential for oxygen transport but is not the element used in insulin for promoting glucose uptake into cells.