TEAS 7 Science Practice Test

Correct Answer: A

Rationale: The correct answer is A because atomic radius generally increases from top to bottom within a group and decreases from left to right across a period on the periodic table. This trend is due to the increasing number of energy levels (shells) as you move down a group, leading to larger atomic radii. Moving from left to right across a period, atomic radius decreases due to increasing effective nuclear charge pulling the electrons closer to the nucleus. Choices B, C, and D are incorrect as they do not accurately describe the trend of atomic radius across the periodic table.

Correct Answer: C

Rationale: The correct answer is C. When two heterozygous mice (WwSs) are crossed, they can produce offspring with genotypes of Ww, WW, ww, Ss, SS, ss. Therefore, the most likely genotype for their offspring is WwSs. Choice A (wwss) is incorrect because it doesn't account for the possibility of capital letters in the genotypes. Choice B (WWSS) is incorrect because it represents the homozygous dominant genotype, which is less likely when crossing heterozygous mice. Choice D (WWSs) is incorrect because it assumes the offspring will have two dominant alleles for the first trait and one dominant allele for the second trait, which is less likely than having both traits in heterozygous form.

Correct Answer: B

Rationale: The primary function of the respiratory system is to facilitate the exchange of oxygen and carbon dioxide in the body. Step 1: During inhalation, oxygen is taken into the lungs. Step 2: Oxygen is then transported to the cells via the bloodstream. Step 3: Carbon dioxide, a waste product, is removed from the body during exhalation. This process is essential for cellular respiration and energy production. Choices A, C, and D are incorrect because speech production, nutrient transport, and organ protection are not the primary functions of the respiratory system.

Correct Answer: C

Rationale: The correct answer is C: Antibodies. Adaptive immunity involves the body's ability to recognize and remember specific pathogens, such as viruses or bacteria. Antibodies are proteins produced by the immune system in response to these specific pathogens, providing targeted defense. In contrast, choices A and B (inflammation and fever) are examples of innate immunity, which are non-specific responses to pathogens. Choice D, phagocytosis, is a component of both innate and adaptive immunity, involving the engulfment and destruction of pathogens by immune cells. However, antibodies represent a key feature of adaptive immunity by specifically targeting and neutralizing pathogens.

Correct Answer: D

Rationale: The correct answer is D: mitochondria. Mitochondria are known as the powerhouse of the cell and are responsible for producing energy in the form of ATP through aerobic respiration. Muscle cells require a significant amount of energy for contraction, making mitochondria crucial in supplying this energy. Ribosomes (choice A) are involved in protein synthesis and are not directly related to energy production in cells. Chloroplasts (choice B) are only found in plant cells and are responsible for photosynthesis, not energy production in muscle cells. Vacuoles (choice C) are primarily involved in storage and maintaining cell structure, not energy production. Therefore, D is the correct answer as it directly relates to the energy needs of muscle cells.