Answer:
Providing a controlled source of water vapour through which water can be vaporized into the plant envoirment.
Explanation:
Humidity ratio is the ratio of the mass of water in air to the mass of dry air. Humidity is needed in some conditions where the air is very dry. In a very dry air setting, there can be excess moisture loss from the plant surface, increasing the Humidity ratio can counter this effects and reduce excess moisture loss.
Things such as coal and oil are limited because they are only found in some places
Answer:
Option A, most closely related to mammals
Explanation:
Insects like arthropods and molluscs have an open circulatory system and thus do have a distinguishable heart. Fish has two chambered heart. Reptiles have three chambered heart. Amphibians too have a three chambered heart.
All mammals and fish have four chambered heart. The right and left sides of the chambers have restricted entry and hence remain intact from each other
Hence, option A is correct
Answer:
1= In living organisms cells are composed of water or we can say that water is one of the important constituent of cells.
2= Hydrogen bonding import man properties to the water such as cohesion, high heat of vaporization, high heat capacity etc.
3= Because of high polarity, all polar substance get dissolve and make it universal solvent.
Explanation:
Solvent is the that part of solution which is present in large proportion and have ability to dissolve the solute. In simplest form it is something in which other substance get dissolve. The most widely used solvent is water, other examples are toluene, acetone, ethanol, chloroform etc.
Water is called universal solvent because of high polarity all polar substance are dissolve in it. Hydrogen is less electronegative while oxygen is more electronegative and because of difference in electronegativity hydrogen carry the partial positive charge while oxygen carry partial negative charge.
Hydrogen bond:
The hydrogen bond is the attraction between the toms which already take part in the other chemical bons. The one atom is hydrogen while other may be oxygen, nitrogen or fluorine.
The hydrogen bonding in water import man y properties in it such cohesion, high heat of vaporization, high heat capacity etc. The hydrogen bond hold the water molecules together.
Water create electrostatic interaction with other polar molecules. The negative end of water attract the positive end of polar molecules and positive end of water attract negative end of polar substance and in this way polar substance get dissolve in it.
Example:
when we stir the sodium chloride into water the cation Na⁺ ions are surrounded by the negative end of water i.e oxygen and anion Cl⁻ is surrounded by the positive end of water i.e hydrogen and in this way all salt is get dissolved.
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