Lecture 18: Thermal Physiology Part 1 Flashcards
A thermal niche is defined as:
a) The specific heat capacity of an environment.
b) The range of temperatures over which a species/population can persist.
c) The ability of an organism to regulate its internal temperature.
d) The constant temperatures of a specific habitat.
b)
In high-altitude environments, animals face challenges due to:
a) High oxygen availability and moderate cold.
b) Low oxygen availability and extreme cold.
c) High heat variation during the day and low humidity.
d) Constant temperatures and abundant thermal refuges.
b)
Conduction is best described as:
a) Transfer of heat through moving particles, such as wind.
b) Direct contact with motionless particles, such as soil.
c) Heat loss via water vapor, such as sweating.
d) Emission of energy from a warm object to cooler surroundings.
b)
Which of the following is an example of radiant heat transfer?
a) A warm ground heating an animal resting on it.
b) Warm air circulating around a moving animal.
c) Heat from a bush radiating to a nearby animal.
d) Loss of heat through evaporation of sweat.
c)
In animals, which of the following mechanisms is involved in heat loss via water vapor?
a) Radiation
b) Conduction
c) Convection
d) Evaporation
d) Evaporation
. With respect to heat flow between animals and their environment, high conductance corresponds to:
a) High insulation and high resistance to heat loss.
b) High insulation and low resistance to heat loss.
c) Low insulation and high resistance to heat loss.
d) Low insulation and low resistance to heat loss.
d)
With respect to heat flow between animals and their environments, low insulation corresponds to _______ heat retention and _______ heat loss.
a) High; high
b) High; low
c) Low; low
d) Low; high
d)
A thick fur coat in mammals provides _______ thermal conductivity and _______ resistance to heat transfer.
a) High; low
b) High; high
c) Low; low
d) Low; high
d)
In aquatic environments, animals with high surface area-to-volume ratios experience _______ rates of heat loss and _______ thermoregulatory efficiency.
a) High; high
b) High; low
c) Low; high
d) Low; low
b)
Animals living in cold climates often have _______ conductance and _______ heat retention compared to those in warmer climates.
a) High; low
b) High; high
c) Low; low
d) Low; high
d)
With respect to heat exchange, blubber in marine mammals reduces _______ and increases _______ to minimize heat loss.
a) Insulation; conductance
b) Conductance; insulation
c) Resistance; insulation
d) Conductance; resistance
b)
Thin body structures in desert animals promote _______ heat dissipation and _______ resistance to heat flow.
a) High; high
b) High; low
c) Low; low
d) Low; high
b)
Animals in tropical environments typically have _______ thermal insulation and _______ heat conductance to manage heat flow.
a) Low; high
b) Low; low
c) High; high
d) High; low
a)
What does the Q10 value represent in physiological systems?
a) The constant temperature of a reaction
b) The rate of a chemical reaction at one temperature compared to 10 degrees lower
c) The maximum temperature at which enzymes function
d) The difference in temperature between two reactions
b)
If a reaction has a Q10 of 1, this means:
a) The rate doubles every 10 degrees.
b) The rate stays constant regardless of temperature changes.
c) The rate triples every 10 degrees.
d) The rate decreases as temperature increases.
b)
At 40°C, a reaction rate is 8. At 30°C (10°C lower), the reaction rate is 4. What is the Q10 value?
a) 1
b) 2
c) 3
d) 4
b) 2
Which of the following is true regarding Q10 values in animals?
a) Most physiological systems have a Q10 between 1 and 2.
b) Most physiological systems have a Q10 between 2 and 3.
c) Q10 values remain constant across all systems.
d) A higher Q10 always indicates better thermal tolerance.
b) Most physiological systems have a Q10 between 2 and 3.
Q10 is calculated as the _______ of a reaction at one temperature divided by the rate at a temperature that is _______ degrees lower.
rate; 10
Animals maintain their body temperature within a reasonable range to ensure proper functioning of _______ and _______.
cells; physiological processes
What is a thermal strategy?
a) A purely behavioral response to environmental temperature changes
b) A combination of behavioral, biochemical, and physiological responses to maintain body temperature
c) The ability to survive in extreme temperatures without adaptation
d) An organism’s method of increasing body heat production
Answer: b) A combination of behavioral, biochemical, and physiological responses to maintain body temperature
Which of the following is the most important physiological parameter in an animal’s thermal physiology?
a) Surface area-to-volume ratio
b) Heat absorption rate
c) Body temperature (T_B)
d) Evaporative cooling capacity
Answer: c) Body temperature (T_B)
What describes an ectotherm?
a) An animal that generates internal heat to maintain body temperature
b) An animal whose body temperature is determined by the environment
c) An animal with a stable body temperature
d) An animal with a variable body temperature
b) an animal whode body temp is determined by the environement
Which term describes an animal with a stable body temperature?
a) Poikilotherm
b) Ectotherm
c) Endotherm
d) Homeotherm
Answer: d) Homeotherm
Ectotherms rely on ________ to determine their body temperature, while endotherms generate ________ to maintain their body temperature.
Answer: the environment; internal heat