Metabolism & Thermoregulation Flashcards
What is ‘thermal biology’ in relation to sea turtles?
how sea turtles depend on heat transfer properties of their environment along with their physical and physiological characteristics.
How do sea turtles control their body temperature?
They use insulation and adjust blood flow to manage heat exchange with their environment.
What are the main ways heat exchange occurs for sea turtles?
radiation, convection, evaporation, and conduction.
What is conduction in the context of heat exchange?
movement of heat through direct contact, such as between metal or water.
How does convection work in heat exchange for sea turtles?
movement of warmer gas or liquid parts to cooler areas.
What factors make up the equation for heat absorption in sea turtles?
R (thermal radiation emitted), C (heat lost through convection), E (heat lost through evaporation), G (heat lost or gained by conduction).
What does Tb stand for regarding sea turtles?
body temperature
What does thermal inertia mean for sea turtles?
the degree to which a turtle’s body temperature approaches that of its surroundings slowly.
How does body size affect thermal inertia in sea turtles?
A larger body size creates heat lag, leading to a longer time for body temperature to equilibrate with environmental temperature.
Why do sea turtles have a constant body temperature despite environmental changes?
Their thermal inertia dampens the temperature changes, allowing them to moderate fluctuations.
What is regional endothermy as seen in green sea turtles?
It’s a unique adaptation where warm muscles improve swimming ability and facilitate long-distance migrations.
How does the temperature of green sea turtles compare to their surrounding water?
Their body temperatures, Tb, can be significantly higher than the water temperatures, Tw, they are in.
What lethal temperature threshold is believed to affect green sea turtles?
It is believed to be around 40º C (104 °F).
How does body temperature change when a sea turtle is in full sun?
For example, a 117 kg green sea turtle’s plastron temperature can rise from 34.5º C to 53.8º C.
What happens to a sea turtle’s body temperature when it enters water?
The external temperature drops significantly, while the inner temperature can rise slightly.
What nesting behaviors are observed in small sea turtles like L. olivacea?
They often nest during windy, cloudy days to reduce heating from solar radiation.
How does basking behavior benefit female sea turtles?
It helps to accelerate egg development and avoid predators.
What unique feature of water aids in maintaining sea turtles’ body temperatures?
Water has convection coefficients that are 100 times greater than air, which helps in heat exchange.
How does swimming activity affect the body temperature of green turtles?
Swimming activity can help raise their body temperature.
What environmental temperatures can lead to cold stunning in sea turtles?
Cold stunning can occur when water temperatures decrease to between 8-10ºC.
How do metabolic rates differ between D. coriacea and C. mydas hatchlings?
D. coriacea hatchlings have a metabolic rate that is three times that of C. mydas and C. caretta hatchlings.
Why do leatherbacks have a significant amount of adipose tissue?
The adipose tissue helps them regulate their body temperature.
What must sea turtles adapt to in terms of thermal biology?
They must adapt mechanisms to respond to heat gain and manage heat loss effectively.
What do the results of studies on sea turtles indicate about their thermal biology?
It is a complex interplay of various biophysical and environmental factors, alongside their anatomical and physiological characteristics.
Why is it important for sea turtles to manage their body temperature?
Proper thermoregulation enables them to maintain optimal functioning and survival in varying environmental conditions.
What contributes to a turtle’s body temperature changes being slower than environmental temperature changes?
The large body size of sea turtles contributes to heat lag and the dampening of temperature fluctuations.
How do sea turtles typically respond to exposure to hot sun during the day?
They undergo mechanisms to avoid thermal stress and overheating.
How does the tissue composition of leatherbacks aid their thermoregulatory abilities?
A thick layer of adipose tissue allows for better regulation of their body temperature.
What role does metabolism play in the thermal biology of sea turtles?
Increased metabolism generates heat, contributing to the overall body temperature of the turtles.
What is the effect of swimming on the temperature of sea turtles?
elevates the body temperature of green turtles due to increased muscle activity.
What physical characteristics assist sea turtles in thermoregulation?
Their large body size and physical insulation from the shell help to moderate body temperature changes.
At what weight did a leatherback turtle’s body temperature reach significant divergence from cold water temperature?
A 417 kg leatherback’s body temperature was recorded at 25.5ºC in 7.5ºC water.
What is the significance of a turtle’s absorptivity in thermal inertia?
affects how quickly/slowly a turtle’s body temperature will align with environmental temperatures.
How does the anatomical design of sea turtles contribute to their heat exchange capacities?
Their skin and body structure enhance their ability to absorb heat and manage energy exchange.
What can the adaptation of warmer pectoral muscles in sea turtles indicate about their lifestyle?
It may suggest enhanced swimming capabilities critical for their long-distance migration patterns.
When thermoregulating, what does it mean for sea turtles to be in a state of ‘chasing’ environmental temperatures?
their body temperatures are continuously lagging behind the surrounding environmental temperatures.
In what way does the behavioral response of sea turtles minimize overheating?
They flip sand onto their bodies to cool down and reduce heat absorption.
How does the high thermal conductivity of water compare to air regarding heat transfer for sea turtles?
Water transfers heat much more efficiently than air, aiding in stabilizing the turtles’ temperatures.
What is the primary role of visible radiation as it relates to sea turtles?
Visible radiation is absorbed by the water, assisting in maintaining a stable environment temperature for sea turtles.
What advantage does the thermal radiation provide to sea turtles?
It allows for the absorption of heat from the sun, helping to regulate their body temperature effectively.
