The primary circulatory vessel in arthropod anatomy typically:
Show answer Hide answer
Answer: A. Lies on dorsal side
Explanation
Arthropod anatomy features a primary tubular heart and main circulatory vessel positioned along the dorsal side. This dorsal heart pumps hemolymph forward into open body cavities to bathe internal organs in nutrient fluid. Valves within the dorsal vessel direct blood flow efficiently through the open circulatory system of the organism. Arthropods possess an open circulatory system where blood fluid flows freely through spaces called hemocoels. The dorsal position of the primary heart contrasts sharply with the ventral nerve cord typical of invertebrates. Ostia are small openings in the dorsal vessel that allow hemolymph to return from body cavities to the heart.
Lying on the ventral side is incorrect because the primary arthropod heart is located dorsally, not ventrally. Lateral placement does not describe the main longitudinal circulatory vessel found in standard arthropod species. Stating the vessel is not present is false since all arthropods possess a functional dorsal heart system.
Related questions
Q1. What is the typical operational lifespan of a mature erythrocyte_____?
Show answer Hide answer
Answer: B. 120 Days
Mature human red blood cells circulate through the vascular system for an average lifespan of 120 days. As erythrocytes age over this period, their cell membranes become increasingly fragile and susceptible to damage. Ol...
Q2. Depressed intercellular CO2 concentrations promote _________ of stomatal apertures.
Show answer Hide answer
Answer: A. Opening
Depressed intercellular carbon dioxide concentrations inside leaves stimulate the active opening of stomatal apertures. Low carbon dioxide signals insufficient substrate for photosynthesis, prompting guard cells to accum...
Q3. The spongy texture of pulmonary tissue stems from the presence of millions of___________?
Show answer Hide answer
Answer: B. Alveoli
Pulmonary tissue features a spongy texture resulting from millions of microscopic thin-walled air sacs called alveoli. These tiny air-filled chambers create an immense surface area packed densely within the thoracic cavi...
Q4. How does the resolving power of an electron microscope compare to the human eye____________?
Show answer Hide answer
Answer: B. 250000X
An electron microscope utilizes focused electron beams to achieve a resolving power far exceeding optical instruments. This advanced technology provides a resolving power roughly two hundred fifty thousand times greater...
Q5. Dietary sodium chloride is consumed primarily to_________?
Show answer Hide answer
Answer: B. produce small amount of hydrochloric acid required for digestion
Dietary sodium chloride provides the essential chloride ions required for the stomach to produce hydrochloric acid. Parietal cells utilize these chloride ions to synthesize gastric acid necessary for optimal protein dige...
Q6. Magnesium is structurally integrated within which of the following biological molecules__________________?
Show answer Hide answer
Answer: C. Chlorophyll
Magnesium is structurally integrated as the central metallic atom within the porphyrin ring of chlorophyll. This specific coordination position allows the molecule to absorb light energy effectively during photosynthesis...