ati teas 7 science

Correct Answer: B

Rationale: The correct answer is B: Benzene. Benzene is an aromatic hydrocarbon because it contains a ring of six carbon atoms with alternating single and double bonds. This delocalized electron system gives benzene its aromatic properties. A, C, and D are incorrect because they do not have the specific structure required for a compound to be classified as aromatic. Ethane (A) and propane (C) are alkanes with only single bonds, while butene (D) is an alkene with a double bond, none of which have the alternating single and double bonds characteristic of aromatic compounds like benzene.

Correct Answer: B

Rationale: The correct answer is B: 23. In humans, each normal cell contains 23 pairs of chromosomes, making a total of 46 chromosomes. The pairs consist of one chromosome from each parent, ensuring genetic diversity. Choices A, C, and D are incorrect because they do not reflect the accurate number of chromosome pairs in a human cell. Option A (46) is the total number of chromosomes, not pairs. Option C (64) and D (32) are not the correct numbers of chromosome pairs in a human cell.

Correct Answer: C

Rationale: The correct answer is C: Diffraction. Diffraction is the phenomenon that explains the bending of light waves as they pass around an obstacle or through an aperture. This occurs when light waves encounter an obstruction or opening that causes the waves to spread out and bend around the edges, leading to interference patterns. Refraction (A) is the bending of light as it passes through different mediums, not around obstacles. Reflection (B) is the bouncing back of light waves when they hit a surface. Dispersion (D) is the splitting of light into its component colors due to differences in wavelength. Therefore, based on the context of the question, diffraction is the most appropriate explanation for the bending of light in this scenario.

Correct Answer: A

Rationale: The correct answer is A: Covalent bond. In a covalent bond, atoms share electrons to achieve a stable electron configuration. This sharing allows both atoms to fill their outer electron shells and form a strong bond. Ionic bonds (choice B) involve the transfer of electrons, not sharing. Metallic bonds (choice C) occur in metals where electrons are delocalized. Hydrogen bonds (choice D) are weak electrostatic attractions between hydrogen and electronegative atoms, not a result of electron sharing. Thus, the correct answer is A because it accurately describes the sharing of electrons between elements to form a covalent bond.

Correct Answer: A

Rationale: The correct answer is A: Neuron. Neurons are specialized cells that transmit electrical impulses in the nervous system. They consist of a cell body, dendrites to receive signals, an axon to transmit signals, and synaptic terminals to communicate with other neurons. The axon is the long fiber that carries the electrical impulses away from the cell body. Myelin is a fatty substance that insulates and speeds up signal transmission along the axon. Dendrites receive signals from other neurons and transmit them towards the cell body. Therefore, the neuron is the fundamental structure responsible for transmitting electrical impulses, making it the correct answer.