TEAS 7 science practice

Correct Answer: C

Rationale: The involuntary reflex arc that withdraws your hand from a hot object involves both the central nervous system (CNS) and the peripheral nervous system (PNS). When your hand touches a hot object, sensory neurons in the PNS detect the heat and send signals to the spinal cord in the CNS. The spinal cord processes this information and sends a signal back through motor neurons in the PNS to move your hand away from the hot object. This coordinated response requires the collaboration of both the CNS and PNS to protect the body from harm. Choice A is incorrect because the reflex arc involves more than just the central nervous system. Choice B is incorrect because the reflex arc involves more than just the peripheral nervous system. Choice D is incorrect because the reflex arc also involves motor neurons, not just sensory neurons.

Correct Answer: A

Rationale: A lysosome is a membrane-bound organelle found in animal cells that contains digestive enzymes. These enzymes are responsible for breaking down various cellular components, such as proteins, lipids, carbohydrates, and even foreign particles like bacteria. This breakdown process is crucial for maintaining cell health and function by recycling and disposing of cellular waste. Options B, C, and D are incorrect because lysosomes are not involved in transporting proteins and lipids throughout the cell (option B), protein synthesis (option C), or cellular respiration (option D). Lysosomes primarily function as the cell's 'recycling center' by breaking down and processing cellular materials.

Correct Answer: A

Rationale: The correct answer is A. The bicep and tricep muscles form an antagonistic muscle pair, where one muscle contracts while the other relaxes. The bicep, located on the front of the upper arm, is responsible for arm flexion (bending the elbow), while the tricep, situated on the back of the upper arm, is responsible for arm extension (straightening the elbow). This opposing action allows for controlled movement at the elbow joint. Choice B, hamstring and quadriceps, are not opposing muscles in the context of the knee joint; the hamstring group flexes the knee, while the quadriceps group extends it. Choices C and D do not represent an opposing muscle pair related to joint movement.

Correct Answer: B

Rationale: Fertilization of the egg by sperm typically occurs in the fallopian tube. After ovulation, the egg is released from the ovary and travels through the fallopian tube, where it may encounter sperm for fertilization. The fallopian tube provides the ideal environment, including necessary nutrients and conditions, for fertilization to take place before the fertilized egg moves towards the uterus for implantation. Choices A, C, and D are incorrect because fertilization does not occur in the ovary, uterus, or vagina. The ovary releases the egg, the uterus is the site for implantation, and the vagina is part of the birth canal but not the typical site for fertilization.

Correct Answer: B

Rationale: The correct answer is the kidneys. The kidneys filter blood and remove waste products through the formation of urine. The liver primarily functions in detoxification and metabolism. The spleen is involved in blood filtering and immune function. The pancreas produces digestive enzymes and insulin, not involved in filtering blood.