3.1.7 Water Flashcards
What is the major component of a cell?
Water
How much water is a cell made up of ?
85%
Why has water got unusual properties ?
Because of its diplomat nature and the subsequent hydrogen bonds
What is a water molecule made up of ?
Two hydrogen atoms and one oxygen atom
How do you describe a water molecules slightly positive and negative charger ?
Dipolar
Where are the slight charger in a water molecule ?
Slightly negative oxygen
Slightly positive hydrogen
What are the bonds between different water molecules called ?
Hydrogen bonds
Why has water got a higher boiling point than expected ?
Because the water molecules stick together so it takes more energy to separate them
What does water act as due to its high specific heat capacity ?
It acts as a buffer again sudden temperature variations making an aquatic environment
What does buffering against sudden temperature changes prevent ?
The denature or enzymes
What does the hydrogen bonds between water molecules mean in terms of energy ?
That a lot of energy is required to evaporate 1 gram of water
What is the energy needed called ?
Later heat of vaporisation
What is the tendency of molecules to stick together known as ?
A cohesion
What allows water to be pulled up through a tube ?
It’s large cohesive forces
Give an example of where water is pulled up through a tube
Xylem vessels
What does surface tension mean
The water surface acts like a skin and is strong enough to support small organisms
How much water is a mammal made up of ?
65%
How is water important in metabolism?
It is used to break down many complex molecules by hydrolysis
Where do chemical reactions involving water normally take place ?
In an aqueous medium
Name the gases water is readily dissolved in ?
Oxygen and carbon dioxide
Name the wastes water readily dissolves in ?
Ammonia
Urea
Name the inorganic ions and small hydrophilic molecules that water readily dissolves in
Amino acids
Monosaccharides
ATP
Why is evaporation an import feature of water ?
Because it cools organisms and allow them to control their temperature
How is water being incompressible important?
It provides support as hydrostatic skeletons of earth worms and turgor pressure in herbaceous plants
