ThermoThermoregulatiregulati

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A SSsyad presentation.

•Table of ContentsTable of Contents

Slide 3 Introduction to Thermoregulation

Slide 4 Types of Thermoregulation

Slide 5 Thermoregulation in Vertebrates.

Introduction to ThermoregulationIntroduction to Thermoregulation

•Thermoregulation is the ability of an organism to keep its body temperature

within certain boundaries.

•This process is one aspect of homeostasis: a dynamic state of stability between

an animal's internal environment and its external environment.

•If the body is unable to maintain a normal temperature and it increases

significantly above normal, a condition known as hyperthermia occurs.

Types of thermoregulation Types of thermoregulation

There are two types of thermoregulation that are used by animals:

•Physiological regulation: Endothermy

This is when an organism changes its physiology to regulate body

temperature.

For example, many mammals tend to sweat in order to lower

temperature and when humans get cold, muscles may shiver in order to

produce heat.

•Behavioral regulation: Ectothermy

This is when an organism changes its behavior to change its body

temperature.

For example, when animals warm up in direct sunlight, they may wish to

find shade to cool down.

Thermoregulation in vertebratesThermoregulation in vertebrates

•Almost all birds and mammals have a high temperature almost constant

and independent of that of the surrounding air. (homeothermy)

•Almost all other animals display a variation of body temperature,

dependent on their surroundings. (poikilothermy)

•There are, however, certain mammals which are exceptions, being warm-

blooded during the summer or daytime, but cold-blooded during the

winter when they hibernate or at night during sleep; such are hedgehogs

and bats.

Temperature control in cold-blooded animalsTemperature control in cold-blooded animals

•Lizards and snakes bask in the sun in the early morning and late evening , and seek shelter around noon.

•Many species of bees and moths flap their wings vigorously to raise the temperature of their flight muscles before taking off.

•Termite mounds are usually oriented in a north-south direction so that they absorb as much heat as possible around dawn and dusk and minimise heat absorption around noon.

Temperature Control in Tuna and SwordfishTemperature Control in Tuna and Swordfish

Fish have long been thought to be cold blooded.

Tuna and swordfish dive deep into the ocean where the water is very cold.

Swordfish are able to raise the temperature of their brains and eyes, which allows faster eye movements when hunting.

Tuna are able to warm their entire bodies through a heat exchange mechanism called the rete mirabile, which helps keep heat inside the body, and minimizes the loss of heat through the gills.

They also have their swimming muscles near the center of their bodies instead of near the surface, which minimises heat loss.

Bibliography:-Bibliography:-

•http://en.wikipedia.org/wiki/Warm-blooded

•http://en.wikipedia.org/wiki/Thermoregulation

•http://darter.ocps.net/classroom/klenk/Fish.htm