ati teas 7 science

Correct Answer: A

Rationale: The correct answer is A: Axon. The axon is responsible for transmitting signals away from the cell body towards other neurons or muscles. It is a long, slender projection of the neuron that carries electrical impulses known as action potentials. The axon is covered by the myelin sheath, which helps to speed up the transmission of signals. Summary: - B: Dendrite receives signals from other neurons and transmits them towards the cell body. - C: Synapse is the gap between neurons where neurotransmitters are released to communicate signals. - D: Myelin sheath insulates and speeds up signal transmission along the axon, but it is not responsible for transmitting signals itself.

Correct Answer: A

Rationale: The correct answer is A: Pulmonary vein. The pulmonary vein is the only blood vessel among the choices that carries oxygenated blood from the lungs back to the heart. The pulmonary artery (B) carries deoxygenated blood from the heart to the lungs. The aorta (C) carries oxygenated blood from the heart to the rest of the body. The vena cava (D) carries deoxygenated blood from the body back to the heart. Therefore, the pulmonary vein is the only blood vessel in the list that fits the description of carrying oxygenated blood from the lungs to the heart.

Correct Answer: C

Rationale: The correct answer is C because the main function of the pancreas is to produce enzymes that help digest food. These enzymes are released into the small intestine to break down carbohydrates, proteins, and fats. Choice A is incorrect as the pancreas does not store or break down food. Choice B is incorrect as nutrient absorption primarily occurs in the small intestine, not the pancreas. Choice D is incorrect as regulating blood sugar levels is primarily the role of the endocrine portion of the pancreas, not its main function.

Correct Answer: B

Rationale: The correct answer is B because "survival of the fittest" refers to the idea that organisms with the best adaptations to their environment are more likely to survive and reproduce, passing on their advantageous traits to the next generation. This concept, coined by Charles Darwin, emphasizes the importance of natural selection in driving evolution. Choice A is incorrect as complexity does not always equate to fitness. Choice C is incorrect as natural selection favors certain traits over others. Choice D is incorrect as survival and reproduction are not solely determined by strength and aggression.

Correct Answer: B

Rationale: The correct answer is B: Lactic acid. When creatine phosphate is used as an energy source for short bursts of muscle activity, it is rapidly broken down into creatine and phosphate. The breakdown of creatine phosphate leads to the production of lactic acid through anaerobic glycolysis. Lactic acid accumulation causes muscle fatigue during intense exercise. A: Glucose is not the breakdown product of creatine phosphate. Glucose is a common fuel for cellular respiration but is not directly produced from creatine phosphate breakdown. C: Carbon dioxide is not the breakdown product of creatine phosphate. Carbon dioxide is produced during the Krebs cycle in aerobic respiration, not from the breakdown of creatine phosphate. D: Creatine is not the breakdown product of creatine phosphate. Creatine is one of the compounds formed when creatine phosphate is broken down, but it is not the final breakdown product.