Chapter 1 List processes needed for the spontaneous origin of life.a. simple molecules must polymerize/assemble into polymers;b. origin of self-replicating molecules / formation of self-replicating molecules;c. simple molecules must become isolated from the surroundings/enclosed in membranes;d. non-living synthesis of simple organic molecules.Outline the role of prokaryotes in the development of an oxygen-rich atmosphere on theEarth.a. early atmosphere was oxygen free;b. some prokaryotes could carry out chemosynthesis;c. cyanobacteria and other varieties developed the ability to photosynthesize;d. used water as hydrogen source so released oxygen;e. oxygen began to accumulate in the atmosphere;f. more photosynthesis than respiration;g. atmosphere changed from a reducing atmosphere to an oxidizing atmosphere;h. current life forms depend upon an oxygen-rich atmosphere;Outline the use of human embryonic stem cells hESC to treat Stargardt’s disease:a. an inherited form of degeneration of retinal layer/photoreceptor cells/blindnesseye genetic disorderb. hESC/stem cells can provide/differentiate into healthy retinal cellsc. injecting hESC/stem cells into the retina/eye can restore vision in animal/human trialsOutline the cell theory:a. living things are composed of cells;b. cells are the basic/smallest unit of life;c. cells come from pre-existing cells;Discuss the endosymbiotic theory for the origin of eukaryotes.a. mitochondria/chloroplasts were once independent prokaryotes;b. microorganisms/prokaryotes taken into cell by endocytosis;c. this larger host cell was heterotrophic; free living prokaryote not digested;d. kept inside cell and perform respiration/photosynthesis;e. new living arrangement mutually beneficial / depend on each other to exist as single organism;f. ancestral eukaryote cell and engulfed prokaryote reproduce as a unit; by binary fissionthe engulfed prokaryote provides energy by aerobic respiration for the eukaryote;g. prokaryote gains protection/nutrition;h. developing into mitochondria/chloroplasts;i. mitochondria/chloroplasts have double membranes suggests engulfing by endocytosisj. mitochondria/chloroplasts have circular naked DNA as prokaryotes;k. mitochondria/chloroplasts have 70S ribosomes as prokaryotes ;l. mitochondria/chloroplasts grow and divide like prokaryotic cells;m. similar size and shape or mitochondria/chloroplasts to prokaryotesn. mitochondria and chloroplasts cannot survive on their ownp. cristae similar to mesosomes / thylakoid have similar structures in prokaryotes;q. but theory cannot be falsified as it predicts something occurring in the past;r. theory does not explain the origins of cilia/flagella/linear chromosomes/meiosis;s. weaker evidence that cilia/flagella evolved from attached bacteria/spirochetes;Explain the importance of surface area to volume ratio as a limit to cell size.a. as volume of a cell increases, the ratio of its surface area to volume decreases;b. rate of exchange of materials/gas/energy is a function of its surface area;c. food/oxygen enters through the surface of cells;d. wastes leave through the surface of cells;e. more metabolic activity in a larger cell means more food and oxygen required;f. rate of production of heat/waste/resource consumption is a function of its volume;g. at low surface area to volume ratios, exchange of materials takes longer/reducedefficiency of exchange / vice versa;h. large volume means longer diffusion time;i. large volume means more wastes produced;j. excess heat generated will not be lost efficiently with low surface area to volume ratio ;k. eventually surface area can no longer serve the requirements of the cell;l. this critical ratio stimulates mitosis;m. thus the size of the cell is reduced and kept within size limits;Describe the characteristics of stem cells that make them potentially useful in medicine.a. stem cells are undifferentiated cells;b. embryo cells are stem cells;c. stem cells have/retain the capacity to divide;d. can be used to produce cell cultures/large number of identical cells;e. can be used to repair/replace damaged/lost cells/tissue;f. stem cells are undifferentiated / have not yet differentiated/specialized;g. can differentiate/specialize in different ways / are pluripotent/totipotent;h. can be used to form a variety of different tissues / form organs;i. used in medical research;j. used in treatment of named disease;k. stem cells are pluripotentDiscuss the advantages and disadvantages of the use of adult stem cells.Advantages:a. adult stem cells can divide endlessly / can differentiateb. adult stem cells can be used to repair/regenerate tissuesc. fewer ethical objections than with embryonic stem cellsd. adults can give informed consent for use of their stem cellse. adult source is not killed / source would not have grown into new human / no death ofembryos used to provide stem cellsf. no rejection problems / patient’s own cells usedg. less chance of cancer/ malignant tumor development than from embryonic stem cellsh. most tissues in adults contain some stem cellsDisadvantages:i. difficult to obtain/collect/find in adult body/very few availablej. some adult tissues contain few/no stem cellsk. adult stem cells differentiate into fewer cell types than embryonic cells /OWTTEExplain how multicellular organisms develop specialized tissues.a. only some genes are expressed in each cell type/tissue;b. tissues therefore develop differently/become differentiated;c. example would be goblet cellExplain how the properties of phospholipids help to maintain the structure of cell membranes.a. phospholipid consisting of head and two tails;b. head is glycerol and phosphate;c. tails are fatty acid chains;d. head hydrophilic and tails hydrophobic;e. hydrophilic molecules/heads attracted to/soluble in water;f. hydrophobic molecules/tails not attracted to water but attracted to each other;g. properties of phospholipids leads to formation of double layer in water;h. stability in double layer because heads on outer edge are attracted to water and tails areattracted to each other in middle;i. phospholipid bilayer in fluid/flexible state because of attraction of non-polar tails to each other;j. fluidity allows membranes to change shape/vesicles to form or fuse with membrane/fluidityallows cells to divide;k. non-polar amino acid side chains attracted to hydrophobic tails;Describe how the structure of the membrane allows the formation of vesicles.a. fluidity of membrane allows change of