Life at the Cellular 4 Flashcards
Name 5 functions of water.
- bathes our cells
- dissolves and transports compounds
- allows compounds to move within and between cells
- participates in chemical reactions
- dissipates heat
Describe the polarity of water.
Water is polar and the oxygen is more electronegative than the hydrogen so attracts the electrons of the covalent bond.
What makes the liquid property of water?
Hydrogen bonds constantly being formed and broken.
When does hydrogen bonding occur?
When Hydrogen is bonding to highly electronegative ions such as oxygen, nitrogen and fluorine.
Give 4 examples of polar (water soluble) molecules.
Sugars, alcohols, aldehydes and ketones.
As carbon dioxide and water are not water soluble, explain how they travel around the body.
Oxygen travels around the body in haemoglobin.
Carbon dioxide travels around the body in bicarbonate.
All charged molecules are hydrophilic/hydrophobic.
Hydrophilic
Why do non-polar molecules organise themselves in water?
To minimise disruption of hydrogen bonding among surrounding molecules.
Define amphiphatic molecules.
Both hydrophilic and hydrophobic i.e phospholipids.
What can phospholipids form?
Liposomes
What do hydrophobic lipids travel around the blood in?
Chylomicrons
What is the water dissociation equation?
H2O equilibrium arrows H+ + OH-
Kw = [H+][OH-]
What is Kw?
Ion product of water
Define strong acids/bases.
Fully dissociates into ions.
Define weak acids/bases.
Partially dissociate into ions.
