Search results
Results From The WOW.Com Content Network
This evaporation increases the tension on the water menisci in the cell walls and decreases their radius, thus exerting tension in the cells' water. Because of the cohesive properties of water, the tension travels through the leaf cells to the leaf and stem xylem, where a momentary negative pressure is created as water is pulled up the xylem ...
Transpiration is the movement of water through a plant and out of its leaves and other aerial parts into the atmosphere. This movement is driven by solar energy. [4] In the tallest trees, such as Sequoia sempervirens, the water rises well over 100 metres from root-tip to canopy leaves. Such trees also exploit evaporation to keep the surface cool.
Yet another theory is that the heat helps protect against frost damage, allowing the plant to germinate and sprout earlier than otherwise. For example, the skunk cabbage generates heat, which allows it to melt its way through a layer of snow in early spring. [4] The heat, however, is mostly used to help spread its pungent odor and attract ...
There are two types of heat the body is adapted to, humid heat and dry heat, but the body adapts to both in similar ways. Humid heat is characterized by warmer temperatures with a high amount of water vapor in the air, while dry heat is characterized by warmer temperatures with little to no vapor, such as desert conditions.
Simplified control circuit of human thermoregulation. [8]The core temperature of a human is regulated and stabilized primarily by the hypothalamus, a region of the brain linking the endocrine system to the nervous system, [9] and more specifically by the anterior hypothalamic nucleus and the adjacent preoptic area regions of the hypothalamus.
Glycerol is a non-ionic kosmotrope forming powerful hydrogen bonds with water molecules. The hydrogen bonds in the glycerol compound compete with the weaker bonds between the water molecules, interrupting ice crystal formation. [7] This reaction between glycerol and water has been used as an antifreeze in the past. Proteins also play a large ...
If intracellular ice forms, it could be lethal to the plant when adhesion between cellular membranes and walls occur. The process of freezing tolerance through cold acclimation is a two-stage mechanism: [4] The first stage occurs at relatively high subzero temperatures as the water present in plant tissues freezes outside the cell.
Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. A thermoconforming organism, by contrast, simply adopts the surrounding temperature as its own body temperature, thus avoiding the need for internal thermoregulation.