adaptive radiation refers to the evolutionary process where

ATI TEAS 7

TEAS 7 practice test science

1. Adaptive radiation refers to the evolutionary process where:

A. A single ancestral species diversifies into multiple descendant species due to ecological pressures in a heterogeneous environment.
B. Two unrelated species evolve similar adaptations in response to similar environments, leading to convergent evolution.
C. A population becomes increasingly well-adapted to its current environment through continued natural selection.
D. The fossil record exhibits gaps or missing links in the evolutionary history of a lineage.

Correct answer: A

Rationale: - Adaptive radiation is a process where a single ancestral species diversifies into multiple descendant species to exploit different ecological niches within a heterogeneous environment. - This diversification occurs due to the different selective pressures present in various habitats, leading to the evolution of distinct traits and adaptations in different descendant species. - Option A accurately describes the process of adaptive radiation, where the initial species undergoes rapid speciation to occupy different ecological roles and adapt to diverse environmental conditions. - Options B, C, and D do not accurately describe adaptive radiation but refer to other evolutionary processes such as convergent evolution, natural selection, and gaps in the fossil record, respectively.

2. Which of the following is the cartilaginous flap that protects the larynx from water or food while still allowing the flow of air?

A. epiglottis
B. bronchioles
C. epithelium
D. tongue

Correct answer: A

Rationale: The epiglottis is the cartilaginous flap that protects the larynx from water or food while still allowing the flow of air. When we swallow, the epiglottis covers the entrance to the larynx, preventing food or liquid from entering the airway and instead directing them towards the esophagus for digestion. Choice B, bronchioles, are small airway branches within the lungs and are not involved in protecting the larynx from food or water. Choice C, epithelium, refers to the tissue that lines the surfaces of organs and structures in the body, but it is not the specific structure that protects the larynx as described. Choice D, tongue, plays a role in taste, speech, and swallowing, but it is not the cartilaginous flap that protects the larynx.

3. What is the Aufbau principle?

A. The principle that electrons fill orbitals in order of increasing energy.
B. The principle that electrons cannot occupy the same orbital with the same spin.
C. The principle that the maximum number of electrons in an orbital is 2n^2, where n is the energy level of the orbital.
D. The principle that the attractive force between an electron and the nucleus is inversely proportional to the distance between them.

Correct answer: A

Rationale: The Aufbau principle states that electrons fill orbitals in order of increasing energy. This principle helps to explain the electron configuration of atoms and how electrons are distributed within the energy levels and sublevels of an atom. By following the Aufbau principle, one can determine the electron configuration of an atom by sequentially adding electrons to orbitals in order of their increasing energy levels, starting with the lowest energy level. Choice B is incorrect as it describes the Pauli Exclusion Principle, which states that no two electrons in an atom can have the same four quantum numbers. Choice C is incorrect as it refers to the formula for calculating the maximum number of electrons that can occupy an energy level. Choice D is incorrect as it relates to Coulomb's law, which describes the electrostatic interaction between charged particles.

4. A botanist wants to determine if environmental temperature affects root growth. What is the independent variable in this study?

A. Temperature
B. Seedlings
C. Light
D. Root length

Correct answer: A

Rationale: The correct answer is 'Temperature.' In an experiment, the independent variable is the factor that is deliberately manipulated or changed by the researcher. In this study, the botanist is specifically investigating how environmental temperature affects root growth, making temperature the independent variable. Choice B, 'Seedlings,' and Choice C, 'Light,' are not the independent variables in this context as they are not the factors being intentionally changed or manipulated. Choice D, 'Root length,' is the dependent variable, as it is the outcome that is being measured or observed in response to the changes in the independent variable, temperature.

5. Which of the following organelles is responsible for food and water storage in the cell?

A. Centriole
B. Lysosome
C. Ribosome
D. Vacuole

Correct answer: D

Rationale: The correct answer is D, Vacuole. Vacuoles are membrane-bound organelles responsible for the storage of various substances such as food, water, and waste in a cell. They help maintain the cell's turgidity and regulate the movement of substances within the cell. Choice A, Centriole, is involved in cell division and organization of microtubules but not food and water storage. Choice B, Lysosome, contains digestive enzymes for breaking down cellular waste material and foreign invaders. Choice C, Ribosome, is involved in protein synthesis rather than storage of food and water.