Practice TEAS Science Test

Correct Answer: B

Rationale: The correct answer is B: 12 NADPH and 18 ATP. In the Calvin cycle of photosynthesis, each molecule of CO2 requires 2 NADPH and 3 ATP for reduction to glucose. Therefore, to reduce 6 molecules of CO2, you would need 6 x 2 = 12 NADPH and 6 x 3 = 18 ATP. This is why choice B is the correct answer. Choices A, C, and D have incorrect combinations of NADPH and ATP that do not match the stoichiometry of the Calvin cycle for the reduction of CO2 to glucose.

Correct Answer: A

Rationale: The correct answer is A: To transport oxygen and nutrients. The cardiovascular system is responsible for circulating blood throughout the body to deliver oxygen and nutrients to tissues and organs. This function supports cell metabolism and overall body function. Choice B is incorrect because while the cardiovascular system does play a role in blood pressure regulation, it is not its primary function. Choice C is incorrect as digestion is primarily carried out by the digestive system. Choice D is incorrect as waste filtration is mainly performed by the excretory system.

Correct Answer: C

Rationale: The correct answer is C: Humerus. The humerus is the long bone found in the upper arm. It connects the shoulder to the elbow joint. The femur (A) is the long bone found in the thigh, the tibia (B) is the larger of the two lower leg bones, and the radius (D) is one of the two lower arm bones. The humerus is the only bone among the choices that is specifically located in the upper arm, making it the correct answer.

Correct Answer: B

Rationale: The primary function of white blood cells is to fight infection. They are key components of the immune system, identifying and attacking pathogens like bacteria and viruses. White blood cells produce antibodies to neutralize invaders. This function helps the body defend against illnesses and maintain overall health. Choices A, C, and D are incorrect because carrying oxygen (A) is primarily done by red blood cells, transporting nutrients (C) is mainly performed by blood plasma, and transporting waste (D) is mainly the role of the kidneys and liver.

Correct Answer: A

Rationale: The correct answer is A: Ectoderm. During embryonic development, the nervous system originates from the ectoderm layer. The neural plate forms from the ectoderm, which further develops into the neural tube and neural crest cells, giving rise to the brain, spinal cord, and peripheral nervous system. The other choices, B: Endoderm, C: Gastroderm, and D: Mesoderm, do not give rise to the nervous system. Endoderm forms the innermost layer of organs like the gut, Gastroderm is not a recognized germ layer, and Mesoderm gives rise to structures like muscles, bones, and connective tissues, not the nervous system.