TEAS 7 Science Practice Test

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.

Correct Answer: B

Rationale: In anaphase of mitosis, chromatids separate and move to opposite poles of the cell, ensuring each daughter cell receives a complete set of chromosomes. This ensures genetic stability and accurate distribution of genetic material. In metaphase, chromosomes align at the cell's equator but do not separate. Prophase is the initial stage of mitosis where chromosomes condense but do not divide, and telophase is the final stage where chromosomes decondense and nuclear envelopes reform. Therefore, anaphase is the correct phase where chromatids divide into chromosomes and migrate to opposite ends of the cell.

Correct Answer: A

Rationale: The correct answer is A: calcium. Bone is primarily composed of calcium phosphate, which provides strength and rigidity to the bone structure. Calcium is crucial for bone formation and mineralization. Magnesium and potassium are important for various bodily functions but are not the primary components of bone. Collagen is a protein that provides flexibility and support but is not an inorganic material found in bones.

Correct Answer: C

Rationale: The correct answer is C, the law of independent assortment. This law states that alleles for different traits segregate independently of each other during gamete formation. This is due to the random alignment of homologous chromosomes during meiosis. The law of segregation (A) describes how alleles of a gene separate during gamete formation. The law of dominance (B) explains that one allele can mask the expression of another in heterozygous individuals. The law of predictive traits (D) is not a recognized Mendelian law and is therefore incorrect. In summary, the law of independent assortment best describes how alleles from different genes segregate independently during gamete formation.

Correct Answer: B

Rationale: The correct answer is B: make observations. This is the initial step of the scientific method because it involves gathering information about a phenomenon or problem. Observations help in identifying patterns, trends, and potential areas for investigation. Forming a hypothesis (A) comes after making observations, as it is a proposed explanation based on those observations. Analyzing data (C) and forming a question (D) also follow after making observations. Making observations is crucial as it sets the foundation for the rest of the scientific method process.