Water

What's the definition of a hydrogen bond?

A chemical bond formed between the positive charge on a hydrogen atom and the negative charge of an adjacent oxygen molecule

What's the definition of viscosity?

A fluids resistance to flow

What's the biological importance of hydrogen bonds?

A high incidence of hydrogen bonding makes it difficult for water molecules to evaporate. When they do, much energy is released and this is involved in cooling mechanisms. Hydrogen bonds, overall, make water a very stable substance

What is a solvent?

A liquid substance which can dissolve a wife range of molecules

What's the definition of colloidal?

A mixture consisting of microscopic particles evenly dispersed throughout another substance, forming a suspension

What's the definition of a liquid?

A state of matter in which all the particles are free to move

What is the biological importance of water having a very high latent heat of vaporisation?

Evaporation for cooling which maintains a constant body temperature

Does water have a higher or lower density when frozen ? And what's the importance of this?

It's lower. This means water freezes top down because ice floats so organisms beneath can survive. Circulation is maintained in large water bodies = helps nutrient cycling e

What'd the biological importance of colloidal?

Large molecules unable to dissociate have charged areas on the surface which attract a layer of water around the molecules. Te water molecules surrounding the large molecules are weakly bound to the molecule and cannot move away from its surface. Such molecules provide an osmotic effect, helping EG to draw water into blood vessels.

What's the biological importance of waters polarity?

When salt is mixed with water, sodium and chloride ions split/dissociate. They do this because the force of attraction between negatively charged part of water molecule and positively charged sodium is greater than the forces between Cl- and Na+ ion.

What's the biological importance of water being amphoteric?

With a PH of 7,water acts as a PH buffer to all enzyme reactions.

What is the definition of latent heat of vaporisation?

The amount of heat needed to turn a substance into a gas

What's the biological importance of water in a liquid state?

It remains liquid over a wide range of temperatures which allows for stability in metabolic reactions and biological processes

What is the definition of density?

It's a measure if mass per unit volume

What's the biological importance of water's compression? Ie it cannot be compressed easily / if at all

It's an excellent support medium for turn or pressure in plants, amniotic fluid for foetus and support for large awatic animals

What's the biological importance of water having a high specific heat capacity?

It's critical for organisms which need to maintain temper twite's for regulation of enzyme activity. It acts as a temperature buffer

What is the definition of transparent?

The ability for visible light to penetrate a substance fully

What's the biological importance of waters molecular mobility?

Individual hydrogen bonds are weak meaning water molecules can move easily, which allows osmosis to take place

What's the importance of water's transparency?

It allows aquatic plants the photosynthesise

Whats the biological importance of water being a solvent?

It can act as a transport medium for polar molecules causing them to dissociate. It removes metabolic wastes eg urea

What's the biological importance of water having a low viscosity?

It enables water to flow easily through tubes of the xylem. It can be used as a lubricant in joints and mucus

What's the definition of amphoteric?

The ability of a molecule to act as an acid or a base .

What's the biological importance of waters cohesion?

Molecules are pulled inwards causing the water to move upward through xylem tissue

What's the definition of molecular mobility?

The ability of a molecule to move freely in a substance

What does specific heat capacity mean?

The amount if energy/heat (J) needed to raise 1kg of water by 1degree Celcius

What's the definition of compression?

The ability for particles to be squashed to decrease their volume

What's the definition of capillarity?

The movement of water within the spaces of a porous mAterisl due to forces of adhesion, cohesion and surface tension

Whats the biological importance of waters capillarity?

The smaller the diameter of a tube, the higher water rises. So water moves upward in soil and through the plants xylem.

What is the biological importance of waters adhesion?

The strong force of attraction between water molecules and walls of xylem allow for transpiration. This is what causes water to be wet.

What's the biological importance of waters surface tension?

The surface of water forms a skin which is strong enough to support small aquatic organisms

What's the definition of adhesion?

The tendency of molecules to be attracted to other molecules of a DIFFERENT type

What's the definition of cohesion??

The tendency of water molecules of a substance to attract one another

What's the definition of polarity?

Uneven distribution of charges in a molecule

What's the definition of surface tension??

Uneven distribution of force at a boundary interface caused by molecular bonding