Which sequence correctly describes the pathways of the nerve impulse during a reflex action?

13. The diagram shows the position of endocrine glands. Structure 3 points to the adrenal gland, which is located on top of the kidney. The adrenal gland secretes adrenaline. A. Thyroxine is secreted by the thyroid gland. B. Adrenaline is secreted by the adrenal gland. C. Progesterone is secreted by the ovaries. D. Testosterone is secreted by the testes. The final answer is B 14. Sister chromatids are two identical copies of a chromosome joined together. They are attached at a constricted region called the centromere. A. Centrioles are involved in cell division, forming spindle fibers. B. Centromere is the region where sister chromatids are joined. C. A chromosome is the entire DNA structure. D. The spinal cord is part of the nervous system. The final answer is B 15. To reduce water loss in dry and hot environments, plants often have adaptations that minimize transpiration. A. A thin transparent upper epidermis would increase water loss. B. Stomata sunken into pits and covered by hairs create a humid microenvironment, reducing the water potential gradient and thus water loss. C. A high density of stomata on the upper surface would increase water loss. D. A very thin cuticle would increase water loss. The final answer is B 16. A reflex action follows a specific neural pathway. The correct sequence is: Receptor* detects the stimulus. Sensory neuron* transmits the impulse from the receptor to the central nervous system. Relay neuron* (interneuron) processes the impulse within the central nervous system. Motor neuron* transmits the impulse from the central nervous system to the effector. Effector* (muscle or gland) produces the response. The final answer is B 17. The structure that prevents backflow of blood from the aorta to the left ventricle is the aortic valve. The aortic valve is a type of semilunar valve. A. Semilunar valves (aortic and pulmonary) prevent backflow from the arteries into the ventricles. B. The bicuspid valve (mitral valve) prevents backflow from the left ventricle to the left atrium. C. The tricuspid valve prevents backflow from the right ventricle to the right atrium. D. Tendon supporting valves refers to the chordae tendineae that support the bicuspid and tricuspid valves. The final answer is A 18. The large intestine's primary functions include water absorption and formation of feces. A. It does not digest all types of food; digestion mainly occurs in the small intestine. B. It is connected to the small intestine, not directly to the stomach. C. It absorbs water, which is a key function. D. The small intestine is the longest part of the intestinal tract. The final answer is C 19. An amoeba lives in freshwater, which is a hypotonic environment. Water constantly enters the amoeba by osmosis. The contractile vacuole collects this excess water and expels it from the cell, preventing it from bursting. This process is called osmoregulation. A. Reproduction is not the function of the contractile vacuole. B. Food storage is done by food vacuoles. C. Osmoregulation is the primary function of the contractile vacuole. D. Synthesizing proteins is done by ribosomes. The final answer is C 20. Spirogyra is a type of green algae, which means it is autotrophic and produces its own food through photosynthesis. Photosynthesis occurs in organelles called chloroplasts. A. A cell wall provides structural support. B. A pyrenoid is a proteinaceous structure within chloroplasts involved in starch synthesis and storage, but the chloroplast itself is the site of photosynthesis. C. Mucilage is a slimy protective layer. D. Chloroplasts contain chlorophyll and are the site of photosynthesis. The final answer is D 21. A solution with the same water potential as its surrounding is described as isotonic. 1. Isotonic: Correct. This term describes solutions with equal solute concentrations and water potentials. 2. Hypertonic and hypotonic: Incorrect. A solution cannot be both simultaneously. 3. Hypotonic and isotonic: Incorrect. A solution cannot be both simultaneously. Only statement 1 is correct. According to the provided