AQA A-level BIOLOGY (7402/1)
Paper 1 Mark scheme 2021
SPECIMEN V1
polymer - ---ASNWERS----long molecules formed from combinations of many monomers joined together
condensation reaction - ---ASNWERS----a chemical reaction in which two or more molecules join and
produces one water molecule
hydrolysis reaction - ---ASNWERS----A chemical reaction that breaks apart a larger molecule by adding a
molecule of water
isomers - ---ASNWERS----Compounds with the same chemical formulae but different structures.
carbohydrates - ---ASNWERS----compounds made from carbon, hydrogen and oxygen (monosaccharides,
disaccharides and polysaccharides), important energy store
disaccharide - ---ASNWERS----two monosaccharides joined together by a glycosidic bond
polysaccharide - ---ASNWERS----many sugar units joined by a glycosidic bond
maltose - ---ASNWERS----α glucose + α glucose
lactose - ---ASNWERS----glucose + galactose
sucrose - ---ASNWERS----glucose + fructose
where is lactose found? - ---ASNWERS----milk
where is maltose found? - ---ASNWERS----germinating seeds
where is sucrose found? - ---ASNWERS----table sugar
cellulose - ---ASNWERS----polymer of β glucose
starch - ---ASNWERS----polymer of α glucose (amylose + amylopectin)
what is the structure of cellulose? - ---ASNWERS----long, unbranched chains of β glucose, insoluble
where is cellulose found? - ---ASNWERS----plant cell walls
why is cellulose strong? - ---ASNWERS----chains linked by h bonds form microfibrils giving high tensile
strength to prevent osmotic lysis
,what is the structure of starch? - ---ASNWERS----long, highly-branched, compact helix and insluble
where is starch found? - ---ASNWERS----energy stores in plants
glycogen - ---ASNWERS----storage form of glucose in animals, compact, highly-branched structure
limits of the Benedict's test - ---ASNWERS----isn't specific or sensitive
what is the test for reducing sugars? - ---ASNWERS----Benedict's test
what colour will the solution be in the presence of reducing sugars? - ---ASNWERS----green → red
(nearer red, higher conc reducing sugar)
what is the test for starch? - ---ASNWERS----iodine test
if starch is present, what colour will the iodine be? - ---ASNWERS----orange → blue-black
covalent bond - ---ASNWERS----a chemical bond in which two atoms share a pair of electrons
ionic bond - ---ASNWERS----the bond between two oppositely charged ions
hydrogen bond - ---ASNWERS----the attraction between a partially positive hydrogen atom(δ+) and a
partially negative atom(δ-)
lipid - ---ASNWERS----compounds mostly made from carbon and hydrogen (triglycerides and
phospholipids), energy store, thermal insulator, for buoyancy and protection
triglyceride - ---ASNWERS----1 glycerol + 3 fatty acid tails joined by an ester bond
glycerol - ---ASNWERS----a three-carbon alcohol with a hydroxyl group(-OH) attached to each
, fatty acid - ---ASNWERS----a carboxylic acid made of a hydrocarbon chain + a terminal carboxyl group
saturated fatty acid - ---ASNWERS----no double bonds between carbon atoms, maximising the number of
hydrogen atoms that can attach to the carbon skeleton.
unsaturated fatty acid - ---ASNWERS----a fatty acid with one or more double bonds between the carbons
(mono or poly)
polar - ---ASNWERS----molecule with partial charges due to a difference in electronegativity
hydrophobic - ---ASNWERS----water repulsion
hydrophillic - ---ASNWERS----attracted to water
what is the test for lipids? - ---ASNWERS----emulsion test
describe the emulsion test - ---ASNWERS----mix with ethanol and add water, white cloudy emulsion =
lipid
amino acid - ---ASNWERS----monomer of proteins
amino acid structure - ---ASNWERS----central carbon atom, hydrogen atom, variable (R) group, carboxyl
group (COOH) and amine group (NH2)
amine group - ---ASNWERS-----NH2
carboxyl group - ---ASNWERS-----COOH
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Nurseking. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $17.99. You're not tied to anything after your purchase.
