Biology II - Spring Final

Photosynthesis

• What are the reactants and products of photosynthesis?

  • Reactants: 6CO₂ + 6H₂O + sunlight

  • Products: C₆H₁₂O₆ + 6O₂

• In what structure of the chloroplast is chlorophyll located in?

  • Thylakoid membranes

• What is the sequence of the different systems in photosynthesis?

  • PSII, ETC, PSI, ATP Synthase

• What is the correct order for the reactions of the Calvin-Benson cycle?

  • Fixation, reduction, and regeneration

Cellular Respiration

• Define fermentation

  • Fermentation is the anaerobic breakdown of glucose

• Why can cristae of the mitochondria be compared functionally to the thylakoid membranes of the chloroplast?

  • Both have the ETC

• What is the final electron acceptor in cellular respiration?

  • The final electron acceptor in cellular respiration oxygen (and the ETC)

• What must each turn in the Krebs cycle regenerate in order to be able to continue?

  • RuBP

• Which event occurs in the fluid portion of the cytoplasm of a cell undergoing glucose

  metabolism?

  • Glycolysis

• Where does fermentation occur within a cell undergoing anaerobic metabolism of

  glucose?

  • Cytoplasm

• What is the end product of glycolysis?

  • 2 pyruvates

• How many CO₂ molecules are generated from each pyruvate that enters the

  mitochondria?

  • 3

• What results if glucose is metabolized under completely anaerobic conditions?

  • 2 NAD+, 2CO2, and either ethyl alcohol or lactate acid

• The main function of cell respiration is to produce ____. energy

• Name and describe the four main steps of aerobic glucose metabolism.

  • Glycolysis - glucose is broken down into 2 pyruvate and the reactions produce 2 ATP and 2 NADH. Occurs in cytoplasm. 2 net ATP yield.

  • Prep Stage - 2 pyruvate is made into acetyl-coA by enzyme coA. Occurs in matrix of mitochondria. No more ATP produced.

  • Krebs Cycle - acetyl-coA transfers to C4 molecule then C6 (citric acid) molecule. Produces 2 more ATP, producing net 4 ATP. 4 CO2, 6 NADH, 2 FADH2 is also produced. Located in the cristae of mitochondria.

  • Electron Transport Chain - 34 ATP produced and 6 H2O as well

• Choose Krebs Cycle, Glycolysis, Electron Transport Chain, or all of these.

  • Occur(s) in the cytoplasm - Glycolysis

  • Occur(s) in a membrane - ETC

  • Require(s) enzymes - All of them

  • ATP Synthase is needed - ETC

  • CO₂ is produced - All of them

  • The most ATP is produced - ETC

  • Require(s) oxygen directly - ETC

DNA

• What is the relationship among DNA, a gene, and a chromosome?

  • DNA (deoxyribonucleic acid) is the molecule that carries hereditary information. Genes are segments of DNA located on chromosomes, chromosomes are composed of DNA and proteins.

• What happens to DNA when a cell divides?

  • DNA replicates

• Define semiconservative.

  • One strand of parental DNA bound to one strand of newly synthesized DNA

• What is the structure of a nucleotide?

  • Nitrogen base, deoxyribose sugar, and a phosphate group

• In DNA, to what do phosphate groups bond to?

  • the deoxyribose sugar, forming the backbone of DNA

• What is the sequence of subunits in the DNA “backbone”?

  • phosphate- sugar - phosphate - sugar-phosphate - sugar

• Complementary base pairs are held together by hydrogen bonds.

• Briefly describe the process of DNA replication according to the 3 enzymes involved.

  • DNA helicase unwinds the double helix of the parental DNA molecule

  • DNA polymerase matches nucleotides that are complementary to parental DNA: leading and lagging strands. DNA polymerase is continuous on the leading strand while Okazaki fragments form on the lagging strand.

  • DNA ligase joins together two new strands of DNA paired with each of the original parental strands on the leading and lagging.

• Choose deoxyribose, phosphate, double helix, hydrogen bonds, or covalent bonds for the

  following structures.

  • Joins sugar to phosphate. covalent bonds

  • Join adenine and thymine, and also guanine and cytosine. hydrogen bonds

  • Like a spiral staircase. double helix

  • Covalently bonded to nitrogen-containing base. sugar and phosphate group

  • Units of the “uprights” of the DNA ladder that do NOT attach to the nitrogen bases. phosphate

  • Watson and Crick are credited with its discovery. double helix

Gene Expression and Regulation

• What is the “one-gene one- enzyme” hypothesis?

  • One gene is coded by one enzyme.

• Compare DNA and RNA.

  • DNA has deoxyribose, RNA has ribose. DNA is double stranded, while RNA is single stranded. DNA is only found in the nucleus, some forms of RNA are found in the cytoplasm and nucleus. DNA has thymine, RNA has uracil.

• If given a sequence of bases in a section of DNA, such as, TACCGATAA, give the corresponding sequence of bases in mRNA?

  • AUGGGCUAUU

• Define transcription and translation

  • Transcription is the process of making an RNA copy of a gene’s DNA sequence

  • Translation is the process that takes the information passed from DNA as a messenger RNA and turns it into a series of amino acids, to be used to create proteins.

• Differentiate between mRNA, tRNA, and rRNA.

  • mRNA - produced in the nucleus. carries genetic information to ribosomes.

  • tRNA - produced in the nucleus. transfers amino acids to ribosomes.

  • rRNA - produced in the nucleolus of the nucleus from DNA template. joins with proteins to form ribosomes.

• Define codon and anticodon.

  • Codons are found on mRNA while anticodons are found on tRNA.

Evolution

• Define natural selection, adaptation, evolution, and genetic drift.

  • Natural selection: the process whereby organisms better adapted to their environment tend to survive and produce more offspring.

  • Adaptation: a change or the process of change by which an organism or species becomes better suited to its environment

  • Evolution: change in the characteristics of a species over several generations and relies on the process of natural selection

  • Genetic drift: change in frequency of an existing gene variant in the population due to random chance

• Contrast microevolution vs. macroevolution.

  • Microevolution is small measurable evolutionary changes within a population from generation to generation. On the other hand, macroevolution is large changes over time and requires speciation.

• How do Darwin’s and Lamarck’s theories of evolution differ?

  • Lamarck believed in acquired characteristics changing an offspring’s phenotype. While Darwin did not, as natural selection is the mechanism for evolution.

• What is fitness, and how do we measure the fitness of an individual?

  • Fitness is reproductive success of an individual relative to other members of the population. Measured by interaction with environment

• Know Darwin, Lamarck, Wallace, Lyell, and Cuvier

  • Darwin - aboard HMS Beagle, Origin of Species, theory of evolution

  • Cuvier - founded paleontology, catastrophism, and believed in fixity of species

  • Wallace - “survival of the fittest,” British naturalist

  • Lyell - Principles of Geology and Uniformitarianism

• Where are the Galapagos Islands located?

  • west of South America (southern hemisphere)

• What factors contribute to mass extension?

  • continental drift and meteorites

• What is speciation?

  • formation of a new species - occurs when a population evolves independently from the original population