Biological Molecules Flashcards

Question

What are peptide bonds?

Answer 1

Condensation reaction which joins two amino acids Can be broken down by hydrolysis

Answer 2

Four: Primary Secondary Tertiary Quaternary

Answer 3

Sequence of amino acids joined by covalent peptide bonds

Answer 4

Hydrogen bonding between r groups on amino acids Creates the 3D shape of protein Can form a Alpha helix and Beta sheet

Answer 5

Additional bonds of the protein structure: - Ionic - Disulphide - Weak hydrophobic interactions

Answer 6

Multiple polypetide chains joined together

Answer 7

Compact, roughly spherical and soluble Form a spherical shape when folding into their tertiary structure: - non polar hydrophobic R groups are orientated towards their center - Polar hydrophillic R groups orientate themselves on the outside of the protein

Answer 8

Calcium ions (Ca2+) Potassium (K+) Sodium ions (Na+) Hydrogen ions (H+) Ammonia (NH4+)

Answer 9

Polar molecules can dissolve in water The polar properties allows water to attract both negative and positive solutes. This allows molecules to be transported in the body.

Answer 10

As polar subtances can be dissolved in water they are easily transported, either in the blood of animals or xylem of plants. Water is transported in the xylem due to transpiration - this occurs due to cohesion of water molecules

Answer 11

High specific heat capacity meaning it takes lots of energy to change the temperature of water This is useful as internal temperatures of plants and animals should remain relatively constant. Water also has high latent heat of vaporisation meaning it takes lots of energy to change the state of water to gas.

Answer 12

Water buffers temperature means it provides a stable environment, in terms of temperature for aquatic organisms Cohesion provides surface tension to water. This enables small invertebrates to move and live on the surface, providing them a habitat away from predators within water. Ice is less dense then water creating an insulating layer on the surface

Answer 13

Macromolecules Non polar - hydrophobic Insoluble in water Dissolve in organic solvents such as ethanol Made up of fatty acids and glycerol

Answer 14

1 glycerol 3 fatty acid chains Glycerol is joined with fatty acids by condensation reactions between them known as an ester bond

Answer 15

Saturated - no double bonds only single between carbons - fully saturated with hydrogen Unsaturated - double bonds between carbons

Answer 16

1. Can transfer energy due to large ratio of energy storing carbon-hydrogen bonds, the breakdown of these release energy 2. Due to the high ratio of hydrogen to oxygen atoms they can act as a metabolic water source. This is because they can release water when oxidised 3. As lipids are large, hydrophobic molecules they are insoluble in water. This means they will not affect the water potential and osmosis. 4. Low in mass meaning lots can be stored in an animal without it increasing the mass and preventing movement

Answer 17

- Made of a glycerol molecule, two fatty acid chains and a phosphate group - Two fatty acids also bond to the glycerol via two condensation reactions, resulting in two ester bonds - One saturated and one unsaturated train

Answer 18

- Hydrophilic head of a phospholipid can attract with water as it is charged - Due to the phosphate being charged, it repels other fats - The fatty acid chain is not charged. It is known as the hydrophobic tail and repels water but will mix with fats - Polar

Answer 19

Hydrophilic heads on outside of bilayer as they can interact with water and polar molecules Hydrophobic tails align inside of bilayer

Answer 20

Sterols Have 4 carbon rings Hydroxyl group at one end Hydrophilic and hydrophobic ends

Answer 21

Impact fluidity Reduce the fluidity of membranes at high temperatures Increase fluidity at low temperatures

Biological Molecules Flashcards

(46 cards)