in which direction do the particles of the medium move in a transverse wave

ATI TEAS 7

ati teas 7 science

1. In which direction do the particles of the medium move in a transverse wave?

A. Perpendicular to the direction of wave travel
B. Parallel to the direction of wave travel
C. In a circular motion
D. Opposite to the direction of wave travel

Correct answer: A

Rationale: In a transverse wave, the particles of the medium move perpendicular to the direction of wave travel. This means that the particles move up and down or side to side as the wave passes through the medium. This motion creates crests and troughs in the wave, leading to the characteristic oscillation observed in transverse waves. Choice B is incorrect because in transverse waves, the particle movement is not parallel to the direction of wave travel. Choice C is incorrect as the particles do not move in a circular motion in a transverse wave. Choice D is incorrect as the particles do not move opposite to the direction of wave travel; they move perpendicular to it.

2. What is the main function of vacuoles in plant cells?

A. To provide structural support for the cell
B. To transport substances in and out of the cell
C. To synthesize proteins and lipids
D. To store water, enzymes, and waste products

Correct answer: D

Rationale: Vacuoles in plant cells primarily function as storage organelles. They store water, enzymes, pigments, and waste products, helping to maintain turgor pressure within the cell. This turgor pressure provides structural support for the plant cell. While vacuoles can also participate in transporting substances within the cell, their main role is storage. The synthesis of proteins and lipids is mainly handled by other organelles such as the endoplasmic reticulum and Golgi apparatus. Choice A is incorrect because while vacuoles indirectly contribute to structural support by maintaining turgor pressure, their primary function is storage. Choice B is incorrect as vacuoles are not primarily responsible for transporting substances in and out of the cell. Choice C is incorrect as vacuoles do not synthesize proteins and lipids; this function is carried out by other organelles.

3. What does the number of protons in the nucleus of an atom determine?

A. Mass number
B. Atomic number
C. Isotope
D. Valence electron count

Correct answer: B

Rationale: The number of protons in the nucleus of an atom is referred to as the atomic number. This atomic number is crucial as it uniquely identifies an element and determines its position on the periodic table. The mass number, on the other hand, represents the sum of protons and neutrons in an atom's nucleus. Isotopes are variants of elements with the same number of protons but differing numbers of neutrons. Valence electron count pertains to the number of electrons in the outermost energy level of an atom, which influences its chemical behavior.

4. Which of the following equations represents a redox reaction?

A. 2H2 + O2 → 2H2O
B. Zn + 2HCl → ZnCl2 + H2
C. 2NaCl → 2Na + Cl2
D. CH4 + 2O2 → CO2 + 2H2O

Correct answer: B

Rationale: A redox reaction involves the transfer of electrons between reactants. In option B, Zn loses electrons to form Zn2+ while H+ gains electrons to form H2. This exchange of electrons demonstrates a redox reaction, making choice B the correct answer. In options A, C, and D, there is no clear transfer of electrons between the reactants, indicating that they are not redox reactions. Option A represents a synthesis reaction, option C represents a decomposition reaction, and option D represents a combustion reaction. These types of reactions do not involve the transfer of electrons between reactants, unlike a redox reaction.

5. What is the building block of DNA?

A. Amino acid
B. Nucleotide
C. Phosphate group
D. Fatty acid

Correct answer: B

Rationale: - Amino acids are the building blocks of proteins, not DNA. - Nucleotide is the correct building block of DNA. A nucleotide consists of a sugar (deoxyribose in DNA), a phosphate group, and a nitrogenous base (adenine, thymine, cytosine, or guanine). - The option 'C) Phosphate group' is incorrect as it is only part of a nucleotide, not the complete building block of DNA. - Fatty acids are not the building blocks of DNA; they are a type of lipid molecule.