Metabolism Flashcards
Q2: Why are the terms “warm-blooded” and “cold-blooded” misleading?
A2: These terms don’t accurately reflect an animal’s body temperature. For example, cold-blooded animals like lizards can maintain body temperatures similar to or even higher than warm-blooded animals through behavioral adaptations.
Q1: What two living animals are often compared to dinosaurs in terms of locomotion and metabolism?
A1: Mammals and birds, which are both warm-blooded.
Q3: What are the more accurate terms to describe animals based on how they regulate body temperature?
A3: Endotherm (animals that control their body temperature through metabolism) and Ectotherm (animals that use behavior to regulate body temperature).
Q4: How do endotherms and ectotherms differ in regulating body temperature?
A4:
Endotherms maintain a relatively constant internal body temperature through metabolism.
Ectotherms rely on external factors like behavior to control their body temperature, which can fluctuate with the environment.
Q5: How can bone histology help differentiate between endotherms and ectotherms?
A5: Bone histology, which involves slicing fossils and examining their structure, reveals patterns in bone cells (osteons). Endotherms and ectotherms lay down these cells in distinctive ways, and dinosaur bones often resemble those of endotherms.
Q6: What role does body size play in temperature regulation, and how does this apply to the Leatherback turtle?
A6: Large body size slows heat loss because volume increases faster than surface area (cube-square law). The Leatherback turtle is an example of gigantothermy, where its large size helps it maintain a stable internal temperature, even though turtles are generally ectothermic.
Q7: What is gigantothermy, and how might it have applied to large dinosaurs?
A7: Gigantothermy refers to large animals maintaining stable internal temperatures due to their size. Large dinosaurs may have used gigantothermy to regulate their temperature, giving them advantages like sustained activity and speed.
Q8: What evidence suggests that some dinosaurs were endothermic?
A8: The structure of dinosaur bones, particularly the pattern of osteons, resembles that of endotherms, suggesting that dinosaurs might have been endothermic, similar to birds and mammals.
Q9: How does body size affect an animal’s ability to maintain a constant internal temperature?
A9: Larger animals have a greater volume relative to their surface area, making them less affected by external temperature changes. This is why large animals like leatherback turtles and possibly some dinosaurs could maintain more stable internal temperatures.
Q10: Did all dinosaurs regulate their body temperature in the same way?
A10: No, larger dinosaurs may have used gigantothermy, but smaller dinosaurs likely had different temperature regulation strategies. The answer is complex, as dinosaurs descended from ectothermic ancestors but some became endothermic like modern birds.
Q11: What does the cube-square law explain in terms of temperature regulation in large animals?
A11: The cube-square law explains that as an animal’s size increases, its volume increases faster than its surface area. This allows larger animals to retain heat more effectively, making them less affected by the external environment.
Q12: Why is it difficult to draw a clear line between ectothermic and endothermic dinosaurs?
A12: The evolutionary transition from ectothermy to endothermy is not clear-cut. Dinosaurs came from ectothermic ancestors, but some likely evolved into endotherms. The exact timing and extent of this transition is still debated.
