During sustained deep-sea foraging, an adult leatherback sea turtle (Dermochelys coriacea) maintains a core body temperature up to 18∘C18^\circ\text{C}18∘C above the surrounding deep ocean water. It generates substantial metabolic heat through continuous, vigorous contractions of its large pectoral flipper muscles.
Using this information, explain why the leatherback sea turtle can be described as exhibiting endothermic behavior.
Explain why it is much more difficult for a small hatchling leatherback turtle to maintain a stable body temperature in cold water compared to a fully grown adult turtle.
Gaseous exchange in insects relies on a system of internal tubes.
Name the muscularly controlled pores located along the lateral exoskeleton of a locust through which air enters and leaves the tracheal system.
At the innermost terminals of this tracheal network, a specialized fluid resides in contact with the respiring muscle fibers. Name the microscopic, highly-branched tubules where this fluid-tissue interface is located.
Explain why large, active multicellular organisms require a specialized, mass transport system to distribute oxygen and nutrients, whereas very small organisms do not.
A student is asked to produce an accurate, low-power scientific drawing of a transverse section of an insect's trachea observed under a light microscope. They have already used a sharp, dark pencil and written a descriptive title. Suggest two other guidelines the student should follow to ensure their biological drawing conforms to standard scientific conventions.
