Difference between STOMATA and SWEAT PORES???

Question

basic structural and functional differences

Answer 1

Both evolved as methods of metabolic regulation.

Sweat pores are involved in thermoregulation, controlling body temperature in warmblooded creatures, endothermic animals. Stomata are a part of the hydroregulation of plants, regulating the plants turgor, nutrient flow, and rate of photosynthesis. The evaporation of water from plants does lower the temperature so does play a part in plants. Since stomata allow gas exchange they are part of multiple biochemical paths while sweat pores are primarily single purpose. A simplified statement is that the sweat pores are as important in maintaining an internal heat balance in animals as the stomata are in maintaining an internal water balance in plants.

Stomata were one of the earliest adaptations to life on land by plants so are common to all plants. But thermoregulation by sweat is more recent so the glands are not found on all animals. Further there are two types of sweat glands apocrine and eccrine with different functions in different organisms that have them. Horses primarily use apocrine glands to regulate their body temperature while humans use eccrine glands.

A really constant internal environment was of prime importance in evolving the brain and its energy uses. This means both regulated energy delivery to the brain and temperature regulation inside the brain so it can function optimally despite external temperatures.

Sweat pores function by secreting fluids to produce a cooling effect by evaporating the sweat on the skin surface. Mammalian thermoregulation varies between the extremes of active vasodilation and sweating down to vasoconstriction and shivering to maintain an endotherm's core temperature.

Eccrine sweat glands and apocrine glands co-evolved in different ways in different animals but serve similar functions in mammals.

http://www.springerlink.com/content/l267...

http://lib.bioinfo.pl/pmid:1778649

Equine sweat glands

http://www.thehorse.com/pdf/anatomy/anat...

Human glands

http://www.aad.org/education/students/gl...

http://www.sweating.ca/apocrine_sweat_gl...

Stomata are the portals that control transpiration and gas exchange for photosynthesis. So as the leaf opens its pores (stomata) the water evaporates. The evaporation pulls water through the xylem, transporting nutrient bearing water from the soil. CO2 and O2 exchange freely through the leaf pores. CO2 supplies carbon while the xylem supplies the water for photosynthesis to proceed and glucose and the waste O2 to be produced.

Stomata on a mass of plants such as a forest release enough water vapor to alter the ambient temperature. This is part of why cities are hotter than surrounding land with dense vegetative cover.

A plant opening or closing their stomata at night has a direct affect on the dewpoint temperature. The stomata on a corn plant close overnight blocking transpiration. By not adding water to the air the dewpoint will fall by several degrees by morning. However this is not seen over plants like wheat that keep their stomata open at night. Wheat continues to transpire moisture into the atmosphere causing the dewpoint temperature to fall only a few degrees overnight in spring.

http://www.crh.noaa.gov/ict/?n=dewclimo1

Stomata are critical to the plants ability to live on land and to be an autotroph translating light energy to chemical energy. Plants, acting together, modulate their local environment by controlling their transpiration rate and timing.

Sweat pores allow mammalian heterotrophs a broad range of climates they can be active in.

http://www.ncbi.nlm.nih.gov/pubmed/35382...

Answer 2

It's important to note that any similarities between these two structures and between their functions are purely superficial -- that is, they are not homologous entities.

You'll learn more if you read up on them yourself, rather than being provided a list here. With that in mind, start your research by visiting:

http://health.howstuffworks.com/sweat.ht...

and

http://www.tvdsb.on.ca/westmin/science/s...