Grade 12 biology exam review Questions with Accurate Answers

Dehydration synthesis - ANSWERSA reaction at which two molecules combine to create a larger molecule taking out H2O. Hydrolysis - ANSWERSA reaction at which a compound reacts with water to produce other compounds. Redox - ANSWERSA chemical reaction where atoms gain or lose electrons (LEO the lion says GER) Neutralization reaction - ANSWERSWhere an acid and a base reacts to form H2O. Lipids - ANSWERSMade out of carbon, hydrogen and oxygen. The role of the lipids is to insulate the organs and joints. The are made up of ester bonds. Protein - ANSWERSMade out of amino acids and bonds are peptide bonds, the protein form enzymes, cell surface markers and cell membrane are protein channels. Carbohydrates - ANSWERSMade up of hydrogen, carbon and oxygen, it is the main source of energy, and the bonds are glycosidic linkages. [->types of carbs= Monosaccharide= one sugar, Disaccharide= 2 sugars, Polysaccharide= many sugars (3 or more).] Nucleic Acid - ANSWERSOrganisms store hereditary and genetic information that determine structural and functional characteristic. Enzymes - ANSWERSLower activation energy and are catalyst. Factors affecting the reactions are temperature, ph, and concentration. (Enzyme shape) = Non-competitive- Does not compete for an active site. = Competitive- Able to enter active site to block normal substrate for Glycolysis - ANSWERSHappens in cytoplasm. 2 ATP are used to make 2 ADP in investment phase, 2 NAD are used to make 2 NADH and in payoff phase 4 ATP are used to make ADP and 2 H2O's are taken out. Pyruvate Oxidation - ANSWERSThis occurs in the mitochondrial matrix 2 pyruvate and a NAD forms 2 NADH ,2 CO2 and 2 acetyl coa Krebs - ANSWERSHappens in mitochondrial matrix. 3 NADPH is made, 2 CO2 is made, 1 FADH is made, and 1 ATP is made. Oxidative phosphorylation - ANSWERSInvolves a series of redox reaction, O2 is used to oxidize electron carriers FADH and NADH to produce ATP. ETC - ANSWERSHappens in the inner mitochondrial membrane, and involves use of high energy to push H+ from the stroma to the inner Thylakoid space. Chloroplast - ANSWERSFound mainly in the cell of the mesophyll (interior tissue of the leaf). Within the chloroplast you have the thylakoid, granum, and stroma. Light dependent - ANSWERSOccurs in the thylakoid and uses H2O and light to produce ATP, NADH and O2. Calvin Cycle - ANSWERSOccurs in the stroma and uses carbon dioxide, ATP and NADH to produce sugar. Photosynthesis - ANSWERSOccurs in plants, leafs are the major location of photosynthesis. CO2 enters and O2 exits the leaf through small holes called stomata. Substrate Leve - ANSWERSATP is formed directly in a catalyst reaction for each glucose molecule made 4 ATP are generated. Oxidative Phosphorylation - ANSWERSATP is formed indirectly and involves a series of redox reaction. The use of O2 to oxidize electron carriers NADH and FADH to produce ATP. DNA - ANSWERSStays within the nucleus and is a double helix shape, A pairs with T. RNA - ANSWERSLeaves the nucleus and is single stranded, T pairs with uracil (u). DNA replication 1 - ANSWERSDNA gyrase relaxes the bonds of the helix. DNA replication 2 - ANSWERSDNA helicase unzips the helix. DNA replication 3 - ANSWERSSIngle stranded binding protein binds to open DNA strands. DNA replication 4 - ANSWERSPrimase creates RNA primers used to start strand synthesis. DNA replication 5 - ANSWERSDNA polymerase III Synthesizes new complementary strands. DNA replication 6 - ANSWERSRNA polymerase I turn DNA into RNA DNA replication 7 - ANSWERSDNA ligase joins remaining gaps. DNA replication 8 - ANSWERSPolymerase III and II check for and correct errors. Replication fork - ANSWERSLittle lines are lagging strands and long straight line is leading strand. Helicase - ANSWERSBreaks down the hydrogen bonds between complementary base pairs. Single stranded binding pairs - ANSWERSJoin into the base pairs to prevent reforming. DNA gyrase - ANSWERSRelieves tension during the stage of replication. Primase - ANSWERSAttaching complementary RNA primers on the exposed template strand. Polymerase III - ANSWERSuse primers to synthesize new DNA from 5, to 3. Polymerase I - ANSWERSGoes along the strand to remove RNA primer DNA ligase - ANSWERSJoins the resulting gaps in the phosphate sugar backbone. Transcriptional - ANSWERSRegulates rate of transcription by proteins called transcription factors. Post- transcriptional - ANSWERSSplicing of introns and joining of exons. Translational - ANSWERSControls rate at which mRNA transcripts translated into proteins. Post-Translation - ANSWERSThe modification of proteins before it leaves the cell membrane. mRNA - ANSWERSThe messenger RNA, carries the code for proteins from DNA. rRNA - ANSWERSWhere protein synthesis occurs. tRNA - ANSWERSTransfer RNA, attaches certain amino acids to the protein's chain by matching mRNA codon with an anticodon. Operon - ANSWERSSequence of DNA that contains the genes necessary to produce proteins required for the metabolic pathway.