introduction to biological molecules

Question 1

carbon

Answer 1

carbon is the basis of living material because of it ability to form four bonds

Question 2

types of carbon based molecules

Answer 2

• simple
• chain
• ring

Question 3

macromolecules

Answer 3

large biological molecules with repeating subunits and many functional groups

• carbohydrates
• lipids
• proteins
• nucleic acids

Question 4

monomers

Answer 4

macromolecules are composed of monomers

monomers join together with covalent bonds to form long chains or macromolecules known as polymers

Question 5

hoe are polymers formed

Answer 5

dehydration reaction
a molecule of water is formed and removed from the reactants that joined during the reaction
energy is required in the form of ATP

Question 6

how are polymers broken down

Answer 6

hydrolysis
- bonds between reactants are broken with the addition of a molecule of water H2O
energy released from the bonds is stored as ATP

Question 7

water

Answer 7

most abundant molecule in the body - 60-95% of fresh living organisms
- acts as a medium in cellular chemical reactions - plays major role in living systems

Question 8

what is water vital for

Answer 8

• universal solvent and transporter (aids movement of chemicals during diffusion)
• lubricant in joints and on tissues
• regulates body temperature i.e. sweat

Question 9

why is water liquid

Answer 9

H bonds relatively weak and easily broken

Question 10

why is water a universal solvent

Answer 10

• all polar molecules and ions are water soluble because they can form H bonds with water
• ions and polar molecules can move/interact freely and take part in cellular chemical reactions

Question 11

nonpolar molecules

Answer 11

• nonpolar molecules repel water molecules and are thus hydrophobic
• nonpolar molecules have no electrical charge and cannot form hydrogen bonds with water

Question 12

what is hydrophobic

Answer 12

molecules that repel water - nonpolar molecules

Question 13

what is hydrophilic

Answer 13

molecules that attract water - polar molecules

Question 14

what are amphiphilic molecules

Answer 14

complex molecules that have a mixture of both hydrophobic and hydrophilic properties

Question 15

surface tension

Answer 15

• tension on the surface film of a liquid caused by the attraction of the particles in the surface layer so as to reduce surface area
• elastic tendency of a fluid surface

Question 16

what is a surfactant

Answer 16

compounds that lower the surface tension between two liquids, between a gas and a liquid, or between a liquid and a solid.
- surfactants may act as detergents, wetting agents, emulsifiers, foaming agents and dispersants