Bio 12 notes
Subject Biological Molecules
#1: Water
● Polarity
○ Oxygen end is slightly negative
○ Hydrogen end is slightly positive
↳ makes water a great solvent + act like a tiny magnet
○ Water molecule -> shaped like a V
● Cohesion
○ Water molecules stick to each other
● Adhesion
○ Water molecules stick to other surfaces
↳ drives transport in living things
, ● Universal solvent
○ Dissolves ions and polar molecules, enabling chemical reactions inside cells
● High specific heat
○ absorbs/releases a lot of heat before changing temperature
↳ helps stabilize body temperature
● Charge attraction
○ Negative side of water -> attract positively charged particle
■ Sodium in salt
○ Positive side of water -> attract negatively charged particle
■ Chloride
↳ attraction pulls apart molecule -> dissolves it
● Hydrogen bonding
○ Water molecules form temporary bonds easily -> help disperse + stabilize
dissolved particles through solution
#2: Acids + Bases + pH Scale
● Acid
○ A substance that donates H+ ions in water (lower pH in scale)
● Base
○ A substance that accepts H+ ions/donates OH- (higher pH in scale)
stomach black baking
acid coffee water soda ammonia
1 2 3 4 5 6 7 8 9 10 11 12 13 14
● Enzymes, proteins, and cell processes work within certain pH range
Subject Biological Molecules
#1: Water
● Polarity
○ Oxygen end is slightly negative
○ Hydrogen end is slightly positive
↳ makes water a great solvent + act like a tiny magnet
○ Water molecule -> shaped like a V
● Cohesion
○ Water molecules stick to each other
● Adhesion
○ Water molecules stick to other surfaces
↳ drives transport in living things
, ● Universal solvent
○ Dissolves ions and polar molecules, enabling chemical reactions inside cells
● High specific heat
○ absorbs/releases a lot of heat before changing temperature
↳ helps stabilize body temperature
● Charge attraction
○ Negative side of water -> attract positively charged particle
■ Sodium in salt
○ Positive side of water -> attract negatively charged particle
■ Chloride
↳ attraction pulls apart molecule -> dissolves it
● Hydrogen bonding
○ Water molecules form temporary bonds easily -> help disperse + stabilize
dissolved particles through solution
#2: Acids + Bases + pH Scale
● Acid
○ A substance that donates H+ ions in water (lower pH in scale)
● Base
○ A substance that accepts H+ ions/donates OH- (higher pH in scale)
stomach black baking
acid coffee water soda ammonia
1 2 3 4 5 6 7 8 9 10 11 12 13 14
● Enzymes, proteins, and cell processes work within certain pH range
