AQA A-LEVEL Biology paper 1 .2020. complete real exam questions and answers ACTUAL EXAM QUESTIONS AND CORRECT ANSWERS WITH RATIONALES ALREADY GRADED A+

AQA A-LEVEL Biology paper 1 .2020. complete real exam questions and answers ACTUAL EXAM QUESTIONS AND CORRECT ANSWERS WITH RATIONALES ALREADY GRADED A+ What are monomers? - CORRECT ANSWER-The smaller units from which larger molecules are made What are polymers? - CORRECT ANSWER-Molecules made from a large number of monomers joined together What are examples of monomers? - CORRECT ANSWER-Monosaccharides, amino acids and nucleotides What happens in a condensation reaction? - CORRECT ANSWER-Two molecules are joined together with the formation of a chemical bond, it involves the elimination of a molecule of water What happens in a hydrolysis reaction? - CORRECT ANSWER-The chemical bond between two molecules is broken, it involves the use of water All life on earth shares a common chemistry ... - CORRECT ANSWER-This provides indirect evidence for evolution The cells of all living organisms contain only a few ... - CORRECT ANSWER-Groups of carbon-based compounds that interact in similar ways Carbohydrates are commonly used by cells as respiratory substrates, - CORRECT ANSWER-They also form structural components in plasma membranes and cell walls Lipids have many uses, including ... - CORRECT ANSWER-The bilayer of plasma membranes, certain hormones, and as respiratory substrates Proteins form many cell structures, they are also important as ... - CORRECT ANSWER-Enzymes, chemical messengers, and components of the blood Nucleic acids carry the genetic code for ... - CORRECT ANSWER-The production of proteins What is the most common component of cells? - CORRECT ANSWER-Water what happens in covalent bonding? - CORRECT ANSWER-atoms share a pair of electrons in their outer shell What happens in ionic bonding? - CORRECT ANSWER-ions with opposite charges attract one another and form an ionic bond what happens in hydrogen bonding? - CORRECT ANSWER-the negative region of a polar molecule is attracted to the positive region of another polar molecule and a weak electrostatic bond is formed between them both what are all chemical processes that take place in living organisms collectively called? - CORRECT ANSWER-metabolism what is a molar solution? - CORRECT ANSWER-a solution which contains one mole of solute in each litre of solution what are atoms? - CORRECT ANSWER-the smallest unit of a chemical element that can exist independently if an atom loses or receives an electron, what does it become? - CORRECT ANSWERan ion What are monosaccharides? - CORRECT ANSWER-The monomers from which larger carbohydrates are made What are examples of common monosaccharides? - CORRECT ANSWER-Glucose, galactose, and fructose What bond does a condensation reaction between two monosaccharides form? - CORRECT ANSWER-Glycosidic how are disaccharides formed? - CORRECT ANSWER-The condensation of two monosaccharides Maltose is a disaccharide formed by condensation of ... - CORRECT ANSWER-Two glucose molecules Sucrose is a disaccharide formed by condensation of ... - CORRECT ANSWERGlucose and fructose Lactose is a disaccharide for bed by condensation of ... - CORRECT ANSWER-Glucose and galactose What are glucoses isomers? - CORRECT ANSWER-Alpha glucose and beta glucose Polysaccharides are formed by ... - CORRECT ANSWER-The condensation of many glucose units Which polysaccharides are formed by the condensation of alpha glucose? - CORRECT ANSWER-Glycogen and starch Which polysaccharide is formed by the condensation of beta glucose? - CORRECT ANSWER-Cellulose what are all monosaccharides and some disaccharides? - CORRECT ANSWERreducing sugars what is reduction? - CORRECT ANSWER-a chemical reaction involving the gain of electrons or hydrogen what is a reducing sugar? - CORRECT ANSWER-a sugar that can donate electrons to another chemical what is the test for reducing sugars known as? - CORRECT ANSWER-the benedicts test why is the test for reducing sugars known as the benedicts test? - CORRECT ANSWER-benedicts reagent is used to test reducing sugars how do you carry out the benedicts test? - CORRECT ANSWER-1. dissolve the food sample in water an equal volume of benedicts reagent in water bath