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64 Cards in this Set
- Front
- Back
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Structural Components of Viruses
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Simplest of biological systems that are not placed in the 3 domains. Viruses lack metabolic machinery of cells (protein coat and genetic material) THEY DO REPLICATE.
Non-cellular, protein coat around nucleic core, DNA or RNA, 4 basic structures: helical, icosahedral,enveloped, complex. |
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Helical Virus Shape
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Capsid - outer shell of virus
Capsomer: functional unit of capsid. (self assemble) |
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Icosahedral Virus Shape
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Self assembled
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Enveloped Virus Shape
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Derived from the host name, host does not recognize as foreign, helical on the inside.
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Complex Virus Shape
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Bacteriophage, Made of head, tail sheath, tail fiber, helical inside of tail.
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Stramenopila
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-Heterotrophs and phototrophs (hair-like projections like flagella).
-Heterotrophs are either parasitic or free-living (algae--> phototrophs) |
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Oomycetes (Stramenopila)
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-Molds, rusts, mildews
-Egg Fungi -Lost plastids -Plant pathogens (potato blight) |
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Diatoms (Stramenopila)
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-Unicellular photosynthetic algae
-shell composed of silica (glass) -generally asexual |
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Golden Algae (Stramenopila)
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-2 flagella
-photosynthetic some mixotrophic or even phagocytotic -indicators of water pollution -Brown Algae: 3 parts --> blade, stipe, holdfast, |
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Cercozoa
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-contain amoebas
-move and feed using pseudopodia -dispersed across many eukaryotic taxa -Chlorarachniophytes & Foraminiferans |
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Radiolarians
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-Marine Protists whose tests are fused into one delicate piece made of silica.
-Axopodia = pseudopodia, radiate from central body and are reinforced by bundles of microtubules. -smaller organisms attach from axopodia -accumulate as ooze on ocean floor. |
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Amoebozoans
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-lobe-shaped
-include gymnamoebas, entamoebas, & slime molds |
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Gymnamoebas (Amoebozoans)
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-large varied group
-live in soil, fresh water, and marine environments -feed on bacteria and detritus |
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Entamoebas (Amoebozoans)
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-parasites that infect classes of vertebrates and some invertebrates
-Dysentery |
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Slime Molds (Amoebazoans)
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-mycetozoans
-once thought of to be fungi because they produce fruiting bodies that aid in spore dispersal - |
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Rhodophyta (red algae)
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-phycoerythrin (accessory pigment); no flagellate stages
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Chlorophyta (green algae)
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-plant-type chloroplasts
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Alveolata
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-Aveoli (small membrane-bound cavities) under plasma membrane
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Dinoflagellates (Alveolata)
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-Usually unicellular
-Marine and freshwater phytoplankton community -Bioluminescent -Symbiotic relationship with coral -central groove |
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Apicomplexans (Alveolata)
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-parasitic
-sexual and asexual -two or more hosts needed -malaria |
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Ciliates (Alveolata)
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-Macronucleus >50 copies of genome (controls everyday function, asexual reporduction)
-Micronuclei, 1-80 copies of genome, required for sexual reproduction -use cilia to move around -Paramecium |
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Euglenids
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-Flagellated: locomotion
-Autotrophic, mixotrophic, heterotrophic |
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Kinetoplastids (Euglenids)
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-1 large mitochondria that houses extranuclear DNA (the kinetoplast)
-Trypansoma brucei (african sleeping syndrome) |
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Euglenids (Euglenids)
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-1-3 flagell, facultatively photosynthetic
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Parabasalids
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-Trichomonas raginalis, inhabits human vagine and male urethra
-Most common pathogenic protozoan infection of humans in industrialized countries -low birth weight, premature, allows for other STD's |
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Diplominadida & Parabasala
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-Lack Plastids
-Mitochondria do not have DNA, electron transport chains, or citric acid cycle enzymes -Both found in anaerobic environments -Diplomonads have 2 nuclei and many flagella (giardia) |
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High Diversity amongst protists
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-Endosymbiotic model
-Cyanobacteria engulfed by ancestral heterotroph |
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What are Protists?
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-Unicellular
-Nutritionally diverse -Usually Aquatic -Sexual and asexual reproduction -possess specialized organelles -highly diverse |
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Protist means...
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"Eukaryote that isn't a fungi, animal, and plant"
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Antibiotic Misuse
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-Indiscriminate use of antibiotics leads to resistant forms of pathogenic bacteria
-antibiotic misuse includes: over prescription, misuse by patients, antibiotics in animal feed and cleaning products -CDC states this is one of the world's largest health problems |
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Bioremediation
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-using prokaryotes to clean up toxic waste
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Prokaryotes in the Ecosystem
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-decomposers
-convert inorganics into usuable forms -strong eukaryotic relationships -bioremediation -antibiotic misuse -produces essential nitrogen |
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Conjugation of Prokaryotes
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-Some DNA transfer possible
-conjugation = recombination of genes (sexual of a kind) |
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Binary Fission
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-Asexual reproduction
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General Structure of Bacteria
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-Flagella, plasmids, pilus, capsule, plasma membrane, cytoplasm, ribosomes, DNA
-Capsule made of polysccahrides |
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Gram Negative and Gram Positive Bacteria
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-Cell wall provides structure and osmotic projection
-Distinguishes between species based on cell wall -Antibiotics work to disrupt peptidoglycan formation LIPPOSACCHARIDE: NEGATIVE ONLY PEPTIDOGLYCAN: POSITIVE ONLY |
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Unifying traits of Prokaryotes
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-No membrane enclosed nucleus
-No organelles -No mitosis or meiosis -Mostly asexual |
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3 Basic morphologies of Bacteria
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-Coccus (grapes)
-Bacillus (elongated) -Spirillian (spaghetti) |
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Prions
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-Misfolded proteins (no nucleic acid)
-Cause degenerative neural diseases -resistent to heat and other sterilization methods -long incubation periods (10 years) -Turn normal proteins into prions by physical contact -from plaques in brain (cavities) -Mad cow disease |
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Viroids
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-small circular single-stranded RNA
-No Protein coat -Do not code for any proteins -causes a lot of agricultural damage -delta-viruses are viral parasites -silences genes -attacks plants -turns hepatitis b --> d |
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Lysogenic and Lytic Pathways
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-Lysogenic have no cell death
-Lytic has cell death |
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Bacteriophage reproduction
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-5 steps to reproduction: attachment, penetration, replication, assembly, release
-2 modes of reproduction: lytic mode and lysogenic |
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Parsimony
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-misleading due to HOMOPLASY
- Homoplasies: another word for analogous traits -The hypothesis that requires the least number of evolutionary events. (Occam's Razor) |
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Monophyletic
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-all members stemming from a common ancestor
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Paraphyletic
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Monophyletic group except the descendants have been removed
-Reptiles remove class aves |
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Punctuated Equilibrium
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-Change occurs at start of new species
-Remain static for majority of their existence -Caveat: behavior, physiology, internal anatomy may change before morphology in fossils. |
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Two basic patterns of evolutionary change
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-Anagenesis: gradual transition of one species
-No splitting from the phylogenetic tree -Cladogenesis: branching of one or more new species from a parent species -very gradual |
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Allopatric speciation
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-odds of increase when population is small and isolated
-genetic drift and natural slelection more effective -small failures |
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Sympatric speciation
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-reproductive barriers evolve between overlapping populations
-results from polyploidy -shifts in habitat and mate preference |
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Patterns of Speciation
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-Allopatric: geological separation
-Sympatric: biologocal factors |
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Reproductive Isolation
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-Barriers to gene flow
-Prezygotic barriers: impede fertilization -postzygotic barriers: prevents successful propogation of offspring |
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Where do Species come From?
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New Breeding population --> Evolution --> reproductive isolation --> New Species --> biodiversity
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Adaptive Radiation
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-Evolution of many species from a common ancestor
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Hardy Weinberg Equilibrium Theory (5 conditions)
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-Migration (gene flow)
-Mutations -Non-random Mating -Natural selection -genetic drift |
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Hardy Weinberg Equilibrium Theorem
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allele and genotype frequncies remain constant in a population between generations
p^2 + 2pq + q^2 = 1 |
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Where do new species come from?
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Evolution: change in allele frequencies in a population over time
-population localized group of interbreeding individuals -gene pool total aggregate of alleles in population. POPULATIONS EVOLVE NOT INDIVIDUALS |
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Plate Tectonics
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-not only are organisms changing over time, the earth is changing as well.
-Ring of Fire (Pacific Area) -Mass Extinction during heterozoic. |
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The Endosymbiotic Model
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-small prokaryotes enter host as prey or parasite (undigested)
-host gain a selective advantage (energy from mitochondria agent) -host and enosymbionts become single organism) |
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Stromatolites
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-Rock-like structures comprised of photosynthetic bacteria (cyanobacteria) and sediment
-lickely the first groups of photsynthetic bacteria -oldest known fossils formed 3.5 BYA |
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From Protobiont to Prokayote
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-Autotrophs
-Chemoautotrophic (relies on chemicals like sulfur derived energy and methane) -Photoautotrophic (relies on sun) |
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Self-Replication
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-RNA: the original heredity unit
-Self replicate/splice -Catalyze reactions -Possess a genotype and phenotype |
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Extraterrestrial Origin
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-Muchison, Australia, 1969- carbonaceous chondrite meteorite falls and found to contain common amino acids
-Analysis of light spectral indicate the existence of organic molecules in interstellar gas and dust. -10-15% is organic |
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Hydrothermal Vents
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-volcanic activity produces a reducing environment
-early life started here -life relied on sulfur, NOT the sun |
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The First Cell
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-Abiotic synthesis of small orgo molecules (monomers --> polymers)
-polymers and monomers made into protobionts -self replication |
