Biology 172 UH MANOA Exam 2 Latest Version Already Passed

Biology 172 UH MANOA Exam 2 Latest Version Already Passed Animal qualities 1. 2. 3. 4. ? (Multicellular eukaryotes, heterotrophs, cells lack cell walls, bodies held together by structural proteins-collagen) What is Collagen? 1. 2. 3. 4. (Most abundant protein in animal bodies, flexible, high tensile strength and elastic resistance) Skin vs Ligament vs Tendon arrangement of collagen? 1skin- dense irregular. 2. Ligament- sheets. 3. Tendon- cable-like Germ layers give rise to 1 2? Tissues and Organs of an embryo Ectoderm Outer layer of cells Endoderm Inner layer of cells forms digestive tube Archenteron digestive tube Blastula, Gastration, Gastrula? Blastula is hollow ball of cells, gastration the cells fold to form a gastrula where a digestive tube begins to form and ecto/ectoderms are created by the folding Diploblastic ectoderm/endoderm Triploblastic ectoderm/endoderm AND mesoderm Bilaterians all multicellular animals other than sponges and cnidarians Bilaterian traits bilateral symmetry and cephalization larva sexually immature and underdeveloped. requires metamorphosis juvenile sexually immature When did animal diversity begin 675-800 million years ago When did the Cambrian explosion occur 525-535 million years ago (earliest fossils of existing phylum) What are the Cambrian hypotheses? Predator prey relationships. Rise in atmospheric oxygen. Evolution of HOX gene What do Hox genes do? regulate and control development of body form 3 major bilateral groups? Deuterostomes, Lophotrochozoa, Ecdysozoa Protostome proto- spiral cleavage. Coelom forms within middle layer. initial opening becomes the mouth Deuterostome Deutero- radial cleavage. coelom forms from outpocketing middle layer. Intial opening becomes anus Placozoa Trichoplax adherens simplest animal sessile no locomotion collar cells create water currents that move through the spongebody via flagellum. individual collar cells are like choanoflagellates sponges have specialized cells but no ? no true tissue spicules calcium structures in sponges for support amoebocytes digest food particles pulled in by water current collar cells ancestral animal resembled? choanoflagellates