ati teas 7 science

Correct Answer: B

Rationale: In mitosis, sister chromatids are separated and move to opposite poles during Anaphase. This is when the spindle fibers shorten, pulling chromatids apart. Metaphase is when chromosomes align in the middle. Telophase is when the nuclear envelope reforms. Cytokinesis is the division of the cytoplasm. Therefore, B is correct as it specifically describes the phase where sister chromatids separate and move to opposite poles.

Correct Answer: B

Rationale: The correct answer is B: Thyroxine. Thyroxine is a hormone produced by the thyroid gland that plays a key role in regulating metabolism. It controls the body's metabolic rate, impacting energy levels and weight. Adrenaline (A) is produced by the adrenal glands and is involved in the fight-or-flight response. Cortisol (C) is produced by the adrenal glands and is known as the stress hormone. Insulin (D) is produced by the pancreas and regulates blood sugar levels, not metabolism. Thyroxine directly influences metabolism, making it the correct choice.

Correct Answer: D

Rationale: The correct answer is D, both transcription and translation. First, DNA undergoes transcription to produce mRNA, which carries the genetic information. Then, during translation, mRNA is used by ribosomes to synthesize proteins. Replication (A) is the process of copying DNA, not directly related to protein synthesis. Transcription (B) is the step where DNA is transcribed into mRNA. Translation (C) is the process where mRNA is translated into proteins. Therefore, both transcription and translation are essential steps in the flow of genetic information from DNA to protein.

Correct Answer: C

Rationale: The correct answer is C: Nucleus. The nucleus is responsible for controlling the activities of the cell because it houses the cell's DNA, which contains instructions for cellular functions. It regulates gene expression and controls the production of proteins. The Golgi apparatus (choice A) is involved in processing and packaging proteins. Mitochondria (choice B) are responsible for energy production. Ribosomes (choice D) are responsible for protein synthesis. However, the nucleus is the main organelle that directly regulates and controls the activities of the cell.

Correct Answer: C

Rationale: The correct answer is C: Diffraction. Diffraction is the phenomenon that explains the bending of light waves as they pass around an obstacle or through an aperture. This occurs when light waves encounter an obstruction or opening that causes the waves to spread out and bend around the edges, leading to interference patterns. Refraction (A) is the bending of light as it passes through different mediums, not around obstacles. Reflection (B) is the bouncing back of light waves when they hit a surface. Dispersion (D) is the splitting of light into its component colors due to differences in wavelength. Therefore, based on the context of the question, diffraction is the most appropriate explanation for the bending of light in this scenario.