topic 2: molecular biology Flashcards
organic
contains carbon in living tissue
carbons which are not organic
carbon dioxide, carbon monoxide, carbonates and hydrogen carbonates
examples of organic molecules
lipids, carbohydrates, nucleic acids and proteins
macromolecules contain…
carbon, hydrogen and oxygen- nitrogen appears in proteins and nucleic acids, phosphorous sometimes appears in lipids
macromolecules
build living cells and take part in chemical reactions
ratio of hydrogen and oxygen in carbohydrates
2:1
types of carbohydrates
monosaccharides, disaccharides, polysaccharides
types monosaccharides
glucose (blood sugar found in the plasma), fructose and galactose (part of lactose)
Disaccharides
two sugars that are joined together. examples: Sucrose (plant sugar), lactose (milk sugar), maltose (would in malt)
polysaccharides
many sugars. examples: cellulose, starch (stored in plants), glycogen (temporarily stored In liver to be broken down)
use of carbohydrates
short term energy, plant cell walls
subunit of carbohydrates
Monosaccharides
examples of proteins
muscles, enzymes, glycoproteins and hormones
use of proteins
defense, transport, contractile movement, catalytic
subunit of proteins
amino acids
examples of lipids
oils/fats, phospholipids, cholesterol and wax
use of lipids
long term energy, storage of glucose (stored in adipose tissue)
subunit of lipids
glycerol fatty acids (they are long chains of carbon and hydrogen)
examples of nucleic acids
RNA and DNA
uses of nucleic acids
RNA- brings the ribosome to build a polypeptide
DNA- turns genes into proteins
subunit of nucleic acids
nucleotides
metabolism
all the enzymatic reactions that take place in a living organism
anabolism
the synthesis of complex molecules from simpler molecules. requires an energy input. this includes the formation of macromolecules from monomers by condensation reactions
catabolism
the breakdown of complex molecules into simpler molecules, a process which releases energy. This includes the hydrolysis of macromolecules into monomers.
hydrolysis reaction
takes polymer molecules and synthesises them into monomer molecules. This requires water
condensation reaction
two monomer molecules join to make a polymer molecule, which produces water
glucose bonds
glycosidic bonds
amino acid bonds
peptide bonds
glycerol bonds
ester
vitalism
organic compounds were thought to have a non physical element which inorganic molecules lacked. Vitalism was falsified because organic molecules can be synthesised artificially
urea
used by the body to excreted oxygen, is high soluble. the artificial synthesis of urea shows that organic molecules are not essentially different from inorganic molecules
water
metabolism takes place in water, water is polar. Water is attracted to other water molecules as a result of its positive and negative infinities
polar molecules
slightly charged regions and different distribution of charge
thermal properties of water
- boiling point
- high specific heat capacity
- high latent heat of vaporisation
cohesion
gives the water surface tension, allowing organisms to move across the surface. Surface tension transmits vibrations. without cohesion, there will be a difficulty in transport of water
surface tension
caused by the cohesive hydrogen bonding resisting an object trying to penetrate the surface.
adhesion
Adhesion is the ability of water molecules to form hydrogen bonds. A large number of hydrogen bonds gives adhesive forces a lot of strength.
adhesion and cohesion
help the transpiration of water
solvent
Water can dissolve many organic and inorganic substances that have charged or polar regions. Water is a good solvent for a lot of different substances; however it is not universal. It is a good transportation medium
solvent and thermal properties of water
- water has a high specific heat capacity, therefore water changes in density based on temperature.
- water has a high heat of vaporisation
hydrophilic
substances are chemically attracted to water. All substances which dissolve in water are hydrophilic. These substances are polar molecules or substances with positive or negative charges.