ati teas 7 science

Correct Answer: B

Rationale: The correct answer is B. Sunscreen protects the skin by absorbing UV rays and converting them to heat. This process prevents the UV rays from penetrating the skin and causing damage. Reflecting UV rays (A) would not be as effective as absorbing them. Blocking UV rays completely (C) is not possible with sunscreen. Stimulating melanin production (D) is not the main mechanism of how sunscreen works to protect the skin.

Correct Answer: D

Rationale: The correct answer is D: Aorta. The aorta is responsible for pumping oxygenated blood to the body. This happens after the oxygenated blood leaves the left ventricle of the heart through the aortic valve. The aorta is the largest artery in the body and carries blood to all parts of the body, supplying oxygen and nutrients. The other choices are incorrect because: A: Right ventricle pumps deoxygenated blood to the lungs. B: Left ventricle pumps oxygenated blood to the body. C: Pulmonary artery carries deoxygenated blood from the heart to the lungs for oxygenation.

Correct Answer: C

Rationale: Rationale: Cytosol is the liquid component of the cytoplasm and is not membrane-bound. Mitochondrion is a membrane-bound organelle responsible for energy production. Therefore, the difference between cytosol and mitochondrion is that the mitochondrion is a membrane-bound organelle, while cytosol is not. Summary: A: Incorrect. Cytosol is not a membrane-bound organelle, and the mitochondrion is also not membrane-bound. B: Incorrect. Cytosol is part of the cytoplasm, and the mitochondrion is also located within the cytoplasm. C: Correct. The mitochondrion is a membrane-bound organelle, while cytosol is not. D: Incorrect. Both the mitochondrion and cytosol are components of the cytoplasm, but the mitochondrion is membrane-bound, unlike cytosol.

Correct Answer: B

Rationale: The correct answer is B: Mitosis. Mitosis is the type of cell division responsible for growth and repair in multicellular organisms. During mitosis, a cell divides into two identical daughter cells, ensuring the growth and repair of tissues. Meiosis (A) is involved in sexual reproduction, not growth or repair. Binary fission (C) is a form of asexual reproduction in prokaryotic cells, not growth or repair. Osmosis (D) is the passive movement of water across a semi-permeable membrane, not a form of cell division.

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.