BIOL 152 1st EditionExam # 2 Study GuideEvidence of Evolution1.) Fossil Record – Documents evolution of new taxa- The order of appearance of organisms reflects their evolutionary relationships- Intermediate (transitional) forms linking groups - Archaropteryx (links birds and dinosaurs)2.) Example of how fossils allow tracing of character evolution:Mammalian middle ear ossicles- Quadrate-incus (anvil)- Articular malleus (hammer)Diffusion1.) In general as cells get larger, surface area to volume ratio _DECREASES___.Why is this significant?Diffusion is better over small distances.2.) Diffusion – fundamental process of substance transport in biological systems. Moves gases wastes, nutrients, etc. into out of between and within cells- Diffusion is a _slow_ process, where efficient transport of substances are limited to _distance__.Bacteria and Archaea1.) Fill in the Cladogram: this is a 3-branched tree of life based on sequence comparisons of the genes for the small subunit of ribosomal RNA. Archaea and bacteria form distinct branches, although they inherited prokaryotic cell organization from a common ancestor.EukaryaArchaea* What do the tick marks represent?-left tick mark: prokaryotic cell organization-right tick mark: eukaryotic cell organization 2.) Properties of Organisms- Obtain food- Exchange gases- Maintain proper water and solute balance- Removes wastes- reproduce3.) BacteriaCharacteristics- Nuclear membrane is (present/absent)- Organelles are (present/absent)- _circular__ chromosomes- (Small/Large) cells- Cell wall? yes or no Gram-positive bacteria vs. Gram-negative bacteria- What is the difference between Gram-negative and Gram-positive bacteria and what is the difference in the arrangement of their layers?-Gram positive will stain; the outside is just a layer of peptidoglycan and then an inner plasma membrane-Gram negative won’t stain b/c it has an outer layer of carbohydrate portion of lipopolysaccharide and then as you go in, its an outer membrane, a peptidoglycan layer, and an inner plasma membrane-Peptidoglycan is absent in archaea4.) ArchaeaCharacteristics- Some are extremophiles__ o What are extremophiles?Archaea that live in extreme environments like acid mines- Nuclear membrane is (present/absent)- Organelles are (present/absent)- _circular_ chromosomes- (Small/Large) cellsBacteria- Cell wall? yes or no*Peptidoglycan is _present__ in bacteria and absent_ in archaea.5.) How does Bacteria and Archaea reproduce?- Asexual-Binary fission (short generation times 20mins-24hours). The prokaryote replicates its genes and divides into 2 daughter cells.- 3 methods of horizontal gene transfer:o Bacterial Conjugation – DNA in a plasmid goes from a donor cell and istransferred through a pilus into the recipient cell o Bacterial transformation – one cell dies, DNA is released into the environment and another cell comes by and takes it upo Bacterial transduction – DNA is transferred via a virus6.) Biogeochemical cycles What is the significance? (carbon cycle, sulfur cycle, nitrogen cycle)The evolution of cyanobacteria resulted in accumulation of oxygen in the atmosphere about 2.4 bya.short term carbon cycle: it’s a back and forth bw photosynthesis and respiration primary producers are major players in carbon cycle (microbial mat has a top layer of photosynthetic cyanobacteria)7.) Name, define, and give an example of the different metabolic strategies thatorganisms use to obtain energy.- Photoautotrophs= they get their energy from the sunlight and carbon fromorganic molecule aka CO2 Plants, algae, and cyanobacteria are photoautotrophs- Chemoautotrophs= they get their energy AND carbon from organic molecules taken up from the environment *chemos use their surroundings to get inorganic molecules but don’t use lightAnimals, fungi, and lots of prokaryotes- Photoheterotrophs= they get their energy from sunlight to make ATP like plants, but rather than making their organic molecules they rely on the environment Bacteria and Archaea- Chemoheterotrophs= they cant make their own organic molecules aka carbon, they have to ingest them. Ex) bacteria, fungi, and protozoa - anoxygenic photosynthesis= these type of organisms are photosynthetic that harvest light energy to drive the synthesis of carbohydrates, but they don’t make oxygen in the processAnoxygenic bacteria absorb sunlight using bacteriocholorophyll (a pigmentsimilar to cholorophylll)It also employs only a single photosystem- so it uses electron donors rather than water. These type of organisms are restricted to sunlit habitats where oxygen is present- aerobic respiration= occurs in the presence of oxygen; CO2 and water is produced. Creates 38 ATP- anaerobic respiration= occurs without oxygen; lactic acid/alcohol is produced; only creates 2 ATP8.) Species Co-evolution- The intimate physical relationship between two organisms in which at leastone of the two species is dependent on the other is called symbiosis. (Name, define, and give an example of each type)o Commensalism=one benefits the other isn’t harmedo parasitism =one benefits at the expense of the othero mutualism= beneficial to both organisms (flashlight fish)EUKARYOTES1.) (Refer to the cladogram on pg. 1) In the cladogram, eukaryotic cell organizationevolved after prokaryotic cell organization. How is this possible? BE SPECIFIC (include hypotheses and evidence)From comparisons of RNA molecules, -endosymbiotic origin of mitochondria and chloroplasts-evidence: they have their own circular genome, cell wall molecules, photosynthetic pigments, phylogenetic evidence2.) Eukaryotic cell organelles function- Endomembrane system – synthesis of proteins & transportso Nuclear envelope- it surrounds the nucleus with a membrane with pores that regulate the passage of proteins & RNAo ER- transport proteins- gatekeepers; move molecules from one place to anothero Golgi body- sorting and packaging proteinso Lysosome- break down waste - Mitochondria – powerhouse; metabolic; energy- Chloroplasts - photosynthesis- Cytoskeleton - support3.) Multicellularity (Simple vs. complex)- Simple Multicellularityo Cell adhesion- cells attach to each other and cell matrixo Little cell to cell communicationo Little differentiation o Typically all functions performed by all cells- Complex Multicellularity o Cell adhesion (Explain)o Cell-cell communication (Explain)o Cell differentiation