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level: Level 1

Questions and Answers List

level questions: Level 1

QuestionAnswer
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How to deconstruct public arguments1 Sentience 2 Sexism and Hierarchies
TrpA1Essential channel for nociceptor (pain receptor) in vertebrates TrpA1+ TrpC1 = pain receptors, part of common opisthokont heritage, universal existence among all metazoans
TrpC1Shared across drosophila, arthropod and vertebrrates
CnidariansEarliest animals, with bona fide, neuronal networks - no brains, with nociceptive avoidance behaviour, they make neuronal nets, they have a shared Depression along the DV axis of the larval cnidarian and embryonic vertebrate.
Shared sentienceBetween all cnidaria and bilateria
Bilaterian brain genesPax6 gets coopted in brain of vertebrates - big eyes
Novelty in bilateriansPax6 gets first coopted into the CNS in bilaterians, no sheet formation yet. Pax6 dependent cell types are the serotonergic neurons of the ventral brain of all bilaterian
DominanceVertebrates: dopaminergic or serotonergic system of the hypothalamus detects dominance and status. It can be modulated
Stag beetle fight1 territorial behaviour 2 significant sexual dimorphism 3 ritualized fight behaviour 4 dominance isnt hierarchy 5 hierarchy requires stable social groups 6 dominance can be encoded by pheromones and not expressed
Species conceptPhenetic species, Ecological species concept, Evolutionary species, Biological species and Recognition Species Concept.
Phenetic SpeciesA set of organisms resembling each other and distinct from other sets.
Ecological Species ConceptDistinct phenetic clusters parasites are a good example
Evolutionary SpeciesAll individuals that share a common evolutionary history
Biological SpeciesGroups of actually or potentially interbreeding natural populations, reproductively isolated from other groups
Recognition Species ConceptDifficulties in describing sexual isolating mechanisms
Anagenesis vs CladogenesisAnagenesis: descent with modification within a single lineage Cladogenesis: evolutionary division of lineages, giving a proliferation of species
Tempos and mode of speciationPunctuated equilibrium and Phyletic gradualism
Punctuated equilibriumThe idea that evolution occurs in spurts instead of following the slow, but steady path that Darwin suggested
Speciation mechanismsPrezygotic and Postzygotic isolation by Dobzhansky
Prezygotic isolationCompatible individuals do not mate. Genetic, ecological and Dobzhansky-Muller theory.
Postzygotic isolationHybrids between members of some groups are less fertile to unfertile.
Dobzhansky-Muller theoryIf speciation involves incompatibility of alleles and genes, then more than 1 genes are involved.
Modes of speciationHybridisation, Instantaneous speciation: single point mutation, chromosomal mutation and polyploidy, Gradual speciation: allopatric, sympatric (driven by co-evolution and lead to character displacement) and parapatric.
Batesian mimicrySimilarity of edible species to non-edible ones. Tends to be more precise and restricted to one sex. There is a limit to the freq of mimics that can be carried. Crosses between them produce one or the other morph
Linkage disequilibriumWhen he genes do not recombine. It decays over time and chromosomal distance
HaplotypeA combination of alleles inherited together. Decay depends on the recombination rate (r) which can be 0 to 0.5. a’ = a – r (ad – bc)
Pin and thrum2 morphotypes, increase outbreeding. Pin is recessive to Thrum. G controls the style and female parts and A controls the anthers.
DioecyHas evolved many times. Allows the partitioning of resources, ensures outbreeding. Involves a non recombining region involved in sex determination.
The mutation theory of the origin of sexOrganisms that have frequent deleterious mutations have a problem. Sex allows the recombination of two degen chromosomes, which can re-establish a good one.
Upper vs Lower jawPremaxilla and Maxilla carried teeth. Only dentary carried teeth.
2 different forms of bone in skull formation1 Dermal bone formation – bone sheet formation directly from mesenchyme 2 Endochondral ossification: Cartilage first and then replaced by bone.
Head of jawed vertebratesChondrocranium: 1st cartilage then replaced by endochondral ossification or bone Viscerocranium or splanchnocranium: cartilaginous and dermal bone
Key embryological componentsHindbrain, Branchial arches Mesodermal Limb buds and Mesodermal somites
Conserved neural crest modulesDiscrete cell populations act as developmental modules They come from specific places and go to specific places And are instructed in specific ways before migration Each cell group is one genetic module, and Migrates into one place: A branchial arch.
Neural CrestMatching between hindbrain Segment (rhombomere), Neural crest in branchial arch And its innervation by hindbrain segment – a gnathostome invention!
Fish Tetrapod transitionA significant paedomorphic event happened: Late adult forms retain features from early larval forms of ancestors Best indicator: eye/head relationship
Teeth as developmental modules1 Serial repetition, early similarity/odontodes 2. Redeployment of programme from outside to Inside/jaw region in placoderms 3. Differences of teeth – heterodonty/homodonty. 4. Loss of teeth – gradual and complete
OdontodeCommon gnathostome stock –Formation of enameloid. 3 tissues: 1 ectodermal enamel, 2 dentine bone
TransitionFrom heterodonty to homodonty. Amniote heterodonty and thecodonty. Primitive condition of Amniotes: teeth along One tooth row.
Tooth lossHappened many times independently. Retrograde tooth loss. Lead to new morphologies