2.1-2.5 Flashcards
Properties of lipids
- source of energy
- waterproofing- insoluble in water
- insulation - slow conductor of heat
- protection- stored around delicate organs
- fats are solid at from temperature, oil is sorted
Properties of triglycerides
- 3 fatty acids, each forms ester bonds with glycerol in a condensation reaction
- excellent source of energy
- low mass- to- energy ratio
- insoluble in water
- important source of water ( release it when oxidised)
Properties of phospholipids
- 2 fatty acids and one phosphate head
- hydrophilic phosphate head
- hydrophobic fatty acid tail
- polar molecule
- can make glycolipids by joining carbohydrates
What are amino acids?
Monomer units used to make polymers called peptides
What is used to text for starch?
Iodine solution
What colour does iodine turn in the presence of starch?
From brown to black
What do you use to test for protein?
Bieruts ( copper sulfate and sodium hydroxide)
What do you use to test for lipids?
Ethanoic solution
What colour does bieruts turn in the presence of protein?
From clear blue to light purple
What colour does ethanoic solution turn in the presence of lipids?
Colourless to white emulsion
What is used to show reducing sugars?
Copper sulfate in Benedicts solution
What sugars with reduce ( add hydrogen to) another substance?
glucose, fructose, other monosaccharides and maltose ( disaccharide)
How do you test for non reducing sugars?
Add substance with HCl- shake- neutralise with sodium hydroxide- then repeat test for reducing sugars
Which food groups must be in aqueous solution for the tests?
Protein, sugars
What is an organic molecule?
Living organisms with carbon
Where is urea formed and why?
In the kidney as a waste product
What is the theory of vitalism?
That all organic compounds could only be made using a vital principle and didn’t conform to the laws of physics or chemistry, so couldn’t be made in labs.
How was the vitalism principle proved wrong
Friedrich Wöhler made urea artificially when trying to make ammonium cyanate
Why haven’t we been able to make all organic compounds yet?
Due to complex protein structures and chaperone proteins
What are examples of carbon molecules in the body?
Carbohydrates
Lipids
Proteins
Nucleic acids
Give some examples of lipids
Steroids, waxed, fatty acids and triglycerides
What are carbohydrates composed of?
Carbon, hydrogen and oxygen. 2 H: 1 O
What are proteins composed of?
One or more chain of amino acids. All of these contain carbon, hydrogen, oxygen and nitrogen, but 2 of the 20 amino acids contain sulphur too.
What are nucleic acids composed of?
Subunits called nucleotides, which contain carbon, hydrogen, oxygen, nitrogen and phosphorus.
What are the 2 types of nucleic acid?
RNA and DNA
Describe the structure of ribose and it’s formula
- C5H10O5
- molecule is a 5 membered ring with a side chain
What is the formula and structure of glucose?
- C6H12O6
- molecule is a 6 membered ring with a side change
What is the structure of a hydroxyl, OH?
-O-H
What is the structure for amine, NH2?
/H
-N
\H
What is the structure of Carboxyl, COOH?
O // -C \ O-H
What is the structure of Methyl, CH3?
H | -C-H | H
Describe the structure of saturated fatty acids
- carbon atoms form an unbranched chain
- bonded by single bonds
- carbon atoms between 14-29
- at one end the carbon is part of a carboxyl group
- at the other end, the Carbon is bonded to 4 Hydrogens
- all other Cs are bonded to 2 Hs
Within an amino acid, what is the carbon in the centre bonded to?
- an amine group
- a carboxyl griuo
- hydrogen atom
- R group, variable part
Draw a simple version of a saturated fatty acid
O OH \\ / C | H-C-H | H-C-H | H
Draw the simple structure of an amino acid
H R O \ | // N-C-C / | \ H H O- H
What is metabolism?
The sum of all the chemical reactions that happen in a cell
What is catabolism?
The breakdown of complex molecules into simpler molecules, including the hydrolysis of macromonomers into monomers
What are some examples of catabolism?
- digestion of food
- respiration ( glucose or lipids are oxidised to CO2 and H2O)
What is anabolism?
The joining together of molecules to make a larger molecule
What are examples of anabolism?
- protein synthesis using ribosomes
- DNA synthesis during replication
What does metabolism consist of?
Catabolism and anabolism