Bio 311c 1st EditionExam # 2 Study Guide- Earth formed 4.6 billion years ago. First life came 3.5 billion years ago.o The first fossil was stromatolites, which are what type of bacteria?- Sources of organic moleculeso Volcanic eruptionso Hydrothermal ventso Meteorso ________________________ list one more- Why is it significant that there was proof of the existence of the nucleotide adenine?o Draw a basic nucleotide.- Energy sourceso Sunlighto heat- Prebiotic soupo Carbono Oxygeno Nitrogeno Hydrogeno phosphate- What s a reducing environment?- Explain what the result of the Miller-Urey experiment proved.- Describe the bubble hypothesis.- Radiometric dating=based on decay of radioactive isotopeso Half-life= the time required for 50% of the parent isotope to decay.o Each isotope has it’s own half lifeo Half life is not affected by temperature, pressure, or other environmental variables.o C14 vs C12 C12 is more common When an organism dies the amount of C12 does not change while C14 decays. Measure ratio---find age.- What kind of evidence is there to prove a fossil is related to a present day species?o Distinct anatomical featureso DNA sequencing- What is the oxygen revolution?o How did species not using O2 respond?- The endosymbiont theory= mitochondria and plastids were formerly small eukaryotes that began living within larger cells (probably entered as undigested prey or parasites). Anaerobic hosts made use of aerobic prokaryotes within.o What does the hypothesis of serial endosymbiosis imply?o Proof of the endosymbiont theory Inner membranes of mitochondria and plastids have enzymes found in plasma membrane of living prokaryotes. Mitochondria and Plastids replicate similarly to certain prokaryotes. Have their own circular DNA Contain ribosomes to turn their own DNA into proteins---reasonably self-sufficient.- 3 Domains of Lifeo Bacteria and Archae are _______________________o Which of the two domains are more closely related?o How do plants, animals, and fungi vary?- Animal cells vs. Plants cells vs. Porkaryotes---------------------------------------LO5----------------------------------------------------------------- Parts of the cellso Nucleus Contains most of the genes in the eukaryotic cell Enclosed by nuclear envelope- Double membrane- Nuclear pores-regulate entry and exit of RNA and proteins and macromolecules- Inside lining is the nuclear lamina made of protein filaments that maintain structure Chromosomes-structures that carry the genetic information- *chromosomes can only be seen when cell is dividing*- Chromatin=complex of DNA and proteins Nucleolus=portion of nucleus that produces ribosomal RNA which is exported through the pores of the envelope to form ribosomes  Process: DNA mRNA+rRNAleave through pores to cytoplasmribosomestranslate mRNApolypeptideo Rough ER Ribosomes attached (that’s why its rough) For protein secretion out of cell usually- Usually glycoproteins Continuous with nuclear envelope Transport vesicles ship proteins out Makes plasma membrane for cell Process: DNAmRNA+rRNA,,>pores of enveloperibosome of Rough ERlumen of rough ERtransport vesiclecell plasma membrane or secretion example=insulin secreted from pancreatic cellso Smooth ER Functions=synthesis of lipids/metabolism of carbs/detox of drugs and poisons/storage of calcium- Lipids=oils/steroids/phospholipids - Steroids=sex hormones/adrenal gland steroid hormones- Ex of cell @testes and ovaries Detox function- Example=liver cells- Usually add hydroxyl group- Draw hydroxyl group- Explain how tolerance increases to drugs or alcohol Calcium storage- Example=help with muscle contraction- Describe the process from signal protein to calcium release into cytoplasmo Golgi Body Vesicle leave ER and enter Golgi body Products of ER (could be lipids from smooth or proteins from rough) are modified, stored, shipped. See more in cells meant for secretion Consists of cisternae=flattened membranous sacs Polarity of Golgi body- Cis face=receive- Trans face=send out !!many polysaccharides secreted by cells are golgi products!!o Vesicles Sacs of membrane Often how proteins/lipids travel through cello Lysosomes =membranous sac of hydrolytic enzymes that digest macromolecules Explain what would happen if a lysosome were to burst inside a cell. Made in rough ERgolgi Responsible for intracellular digestion- Phagocytosis=engulf smaller organismo May be considered food vacuoleo Fuses with lysosome and is digested by enzymeso Products diffuse into cytosolo Ex=macrophages=white blood cells that engulf foreign invaders in the human body- Autophagy=vesicle is created around a damaged part of cell that fuses with lysozyme and is broken down Tay-Sach’s disease=lipid digesting enzyme does not work and brain becomes impaired because of accumulation of lipidso Mitochondria Responsible for cellular respiration Describe cellular respiration. Parts of mitochondria- Outer membrane=smooth- Intramembranous space- Inner membrane= cristae=inholdings…create larger surface area- Mitochondrial matrix=contains enzymes/mitochondrial DNA/ribosomeso Chloroplast Not found in ____________ cells Site of photosynthesis Describe photosynthesis. Part of chloroplast- Chlorophyll=green pigment- Thylakoids=flattened interconnected sacso A stack of thylakoids=granumo Stroma=fluid outside the thylakoid Contains DNA/ribosomes/enzymeso Peroxisomes =metabolic compartment contains enzymes that remove Hydrogen from subtrates to form O2 and produce hydrogen peroxide ex=break down fatty acids ex=detoxify alco Vacuoles =large vacuoles derived from endoplasmic reticulum and golgi apparatus selective membrane types of vacuoles- foodo formed by phagocytosis- contractileo pump excess water out of cello good for cells that live hypotonic environments- centralo forms by combo of smaller vacuoleso Are you more likely to find this in a plant or animal cell?o Contains cell sap=inorganic ions- misco may be used as storageo may store poisonso Cytoskeleton  Function- Give shape- Support- Anchorage for organelles- Cell motilityo Motor proteins Microtubules- Hollow tubes- largest- Made of tubulin dimer (alpha and beta)- Centrosomes= microtubules grow out (like star)o Located near nucleus usuallyo Centrioles=pairs within centrosomeso IN ANIMAL CELLS ONLY- Functiono Resist