What property of a wave determines its pitch in sound waves?

Correct Answer: B

Rationale: The pitch of a sound wave is determined by its frequency. Frequency is the number of cycles of a wave that occur in a given time period. Higher frequencies correspond to higher pitches, while lower frequencies correspond to lower pitches. Amplitude refers to the intensity or loudness of a sound wave, wavelength is the distance between two consecutive points in a wave, and speed is the rate at which a wave travels through a medium. Therefore, in sound waves, it is the frequency that primarily determines the pitch, making option B the correct answer.

Correct Answer: D

Rationale: In the context of classification, 'monophyletic' refers to a group that includes a common ancestor and all of its descendants. This group shares a single evolutionary origin and forms a complete branch on a phylogenetic tree. Monophyletic groups are considered natural and valid taxonomic units because they reflect evolutionary relationships accurately. Option D is the correct choice as it accurately defines the term 'monophyletic' in the context of classification. Choices A, B, and C are incorrect. Choice A is incorrect because 'monophyletic' does not refer to a group with a single representative organism but rather a group descended from a common ancestor. Choice B is incorrect as a monophyletic group consists of related, not diverse and unrelated, members. Choice C is incorrect as a monophyletic group includes descendants from a common ancestor, not just organisms with similar functions but different origins.

Correct Answer: A

Rationale: The correct answer is 'Mutualism.' Mutualism is a type of symbiosis where both organisms involved benefit from the interaction. This relationship is characterized by cooperation and mutual support, leading to advantages for both parties. In mutualistic relationships, each organism provides something that the other needs, resulting in a mutually beneficial outcome. In contrast, 'Commensalism' (choice B) involves one organism benefiting while the other is unaffected, 'Parasitism' (choice C) benefits one organism at the expense of the other, and 'Predation' (choice D) benefits the predator while harming the prey. Examples of mutualism include the relationship between bees and flowers (pollination) and the partnership between nitrogen-fixing bacteria and leguminous plants.

Correct Answer: D

Rationale: A) The fossil record provides evidence of how organisms have changed over time, showing transitional forms and the progression of species. B) Comparative anatomy involves studying the similarities and differences in the structures of different species, which can reveal common ancestry and evolutionary relationships. C) Biogeography examines the distribution of species around the world, which can be explained by evolution and continental drift. By considering all of the above evidence together, scientists can build a comprehensive understanding of evolution and how species have changed and diversified over time.

Correct Answer: A

Rationale: Mass is a measure of the amount of matter in an object and remains constant regardless of changes in gravity. Weight, on the other hand, is the force of gravity acting on an object and can vary depending on the strength of gravity. Volume is the amount of space an object occupies, and density is the mass per unit volume of a substance, both of which can change with changes in gravity. Therefore, mass is the property that remains the same regardless of variations in gravitational force. Choice B, Weight, changes with gravity as it is a force dependent on gravity. Choices C and D, Volume and Density, can be affected by changes in gravity as they are related to the space an object occupies and the mass per unit volume, respectively.