CVA Final Exam (Answered) 2022 Graded A+

CVA Final Exam (Answered) 2022 Graded A+ evolution changes in the genetic makeup of populations of animals through time - change in genetics eventually leads to changes in phenotype recapitulation similarities in embryonic developmental stages of different species is evidence that the embryos are repeating the developmental stages of the ancestors mosaic evolution parts of the body can change independent of others homology similarity in organs from different organisms as a result of inheritance from COMMON ancestors analogy functional similarity among non homologous organs (like butterfly and bird wings) Darwin's reasoning behind natural selection -animals have high reproductive potential and if unchecked will deplete resources -heritable variation between organisms -competition for resources allows the most fit attributes to be passed on with survivors monophyletic group a group with the ancestor and all of its descendants character states various forms of individual attributes derived characters evolutionarily changed and used to delineate relationships transformation series change in character states through time within a clade (ex transition to land) outgroup analysis used to assess patterns of change by establishing polarity (direction of change) outgroup taxa closely related lineages to the one of interest polarity patterns of change or stasis vestigiality organs that are no longer being used for their original function atavism throw back structures - present in ancestors but rare in most individuals today Fossil Biases -they are always morphologically based and not molecular -include only skeletal elements (like teeth since its so hard) -mainly found in fluvial or arid environments -large animals are more commonly found heterochrony evolutionary change to developmental timing or rates anatomical position the standard position an animal should be in before we embark on explaining direction and movement bilateral symmetry body is divided by a mid-sagittal plane forming two mirror images Lateral away from midline (farther from the middle) medial closer to the midline proximal closer to the top of the appendage distal closer to the tip of the appendage (farther from the start) frontal plane divides an animal into dorsal and ventral dorsal above the frontal plane (top when laying down) ventral under the frontal plane (belly) transverse plane plane dividing the front and back cranial (anterior) towards the head caudal (posterior) towards the tail flexion bending of two parts towards one another usually across a joint extension increasing the gap between two parts through bending adduction bringing the structure towards the midline abduction moving a structure away from the midline rotation pivoting about an elements axis protraction moving a structure forward retraction moving a structure backwards from which it came Key features of vertebrate 1. vertebral column attached to notochord 2. two semicircular canals 3. radial fin muscles 4. dermal bone (armor) Features in vertebrate outgroups head, notochord, post-anal tail, pharyngeal slits, endostyle, dorsal nerve tube, myomeres, dorsal and ventral aorta Craniata group hagfish (myxiniformes) and vertebrata Craniate key features braincase, neural crest cells, complex sense organs, cranial nerves, tripartite brain, respiratory gills, muscular gut tube, heart, and hemoglobin Neural crest cells give rise to cranial nerves, meninges of the brain, braincase, gill bars and bones (in vertebrates) sensory placodes ectoderm that invaginates to form sensory structures like nose, lateral line and lens of eye semicircular canals to sense pitch, roll and yaw