what is the electron configuration of an atom

ATI TEAS 7

TEAS 7 science practice questions

1. What does the term 'electron configuration' refer to in relation to an atom?

A. The arrangement of electrons in an atom's orbitals.
B. The number of protons in an atom's nucleus.
C. The number of neutrons in an atom's nucleus.
D. The number of electrons in an atom's valence shell.

Correct answer: A

Rationale: The electron configuration of an atom refers to the arrangement of electrons in the atom's orbitals. This arrangement determines the atom's chemical properties and behavior. The number of protons in an atom's nucleus (option B) is known as the atomic number, which defines the element. The number of neutrons in an atom's nucleus (option C) contributes to the atom's mass number. The number of electrons in an atom's valence shell (option D) is important for understanding the atom's reactivity and bonding behavior, but the electron configuration specifically refers to how electrons are distributed among the different orbitals in an atom.

2. A researcher wants to investigate the relationship between family income and quality of medical care. Which statement provides the best reason to conduct this investigation?

A. The researcher can identify affordable medical care to recommend to low-income families.
B. The investigation can help identify individuals who are healthy so they can maintain their health.
C. Results of this investigation may identify a group of people who do not receive quality medical care and could benefit from improved medical treatments.
D. There is a valid reason to conduct this investigation.

Correct answer: C

Rationale: The correct answer is C because identifying a group of individuals who do not receive quality medical care can lead to targeted interventions to improve their access to better medical treatments. This investigation can help address disparities in healthcare and improve outcomes for those in need. Choice A is incorrect because the focus is on identifying those who lack quality medical care, not just affordable care. Choice B is incorrect as it misinterprets the purpose of the investigation, which is to improve medical care for those not receiving quality care, rather than maintaining the health of those already healthy. Choice D is too vague and does not provide a specific reason for conducting the investigation, unlike choice C which highlights the potential benefits of identifying individuals in need of improved medical treatments.

3. What are the differences between RNA and DNA?

A. Both have the same structure and function.
B. RNA is single-stranded, while DNA is double-stranded.
C. RNA contains ribose sugar, while DNA contains deoxyribose sugar.
D. RNA has adenine and guanine, while DNA has thymine and cytosine.

Correct answer: B

Rationale: A) This statement is incorrect. RNA and DNA have different structures and functions. RNA is involved in protein synthesis and other cellular processes, while DNA stores genetic information. B) This statement is correct. RNA is typically single-stranded, while DNA is double-stranded, forming a double helix structure. C) This statement is correct. RNA contains ribose sugar in its backbone, while DNA contains deoxyribose sugar. D) This statement is incorrect. RNA contains adenine, guanine, cytosine, and uracil, while DNA contains adenine, guanine, cytosine, and thymine. Choice B is the correct answer as it accurately describes one of the key differences between RNA and DNA, emphasizing their structural disparity in terms of single-strandedness for RNA and double-strandedness for DNA. Choices A, C, and D contain inaccuracies regarding the structural and compositional distinctions between RNA and DNA, making them incorrect choices.

4. What is the principle behind the phenomenon of refraction, where waves bend when entering a new medium?

A. Change in wavelength
B. Change in frequency
C. Change in wave speed
D. None of the above

Correct answer: C

Rationale: Refraction occurs due to a change in wave speed when waves enter a new medium. As waves travel from one medium to another, their speed changes, causing them to bend. This change in speed is responsible for the bending of waves during refraction. It is not the change in wavelength or frequency that causes refraction, but rather the change in speed as waves move through different mediums. Therefore, the correct answer is the change in wave speed (Choice C). Choices A and B are incorrect as refraction is not primarily influenced by changes in wavelength or frequency, but by changes in wave speed. Choice D is also incorrect as there is a specific principle, which is the change in wave speed, behind the phenomenon of refraction.

5. Which transport mechanism uses vesicles to move materials out of the cell?

A. Endocytosis
B. Active transport
C. Diffusion
D. Exocytosis

Correct answer: D

Rationale: Exocytosis is the transport mechanism that uses vesicles to move materials out of the cell. Vesicles carry substances to the cell membrane, fuse with it, and release their contents outside the cell. This process is essential for secreting molecules such as hormones, enzymes, or neurotransmitters. Endocytosis, on the other hand, is the process of bringing materials into the cell by engulfing them in vesicles. Active transport involves the movement of molecules across a cell membrane against their concentration gradient, requiring energy. Diffusion is the passive movement of molecules from an area of higher concentration to an area of lower concentration.