Study Guide Lecture Exam 1 Flashcards
What are the major characteristics of animals?
Multicellular, eukaryotic, lack a cell wall (cell membrane only).
What are the three major types of body symmetry?
Radial (central axis), Bilateral (left/right sides), Asymmetry (no symmetry).
What is the difference between protostomes and deuterostomes?
Protostomes: Mouth first, spiral cleavage, determinate division. Deuterostomes: Anus first, radial cleavage, indeterminate division.
What are the major stages of embryonic development in order?
Zygote → Cleavage → Morula → Blastula → Gastrula.
What are the three ways of classifying animals based on body cavity type?
Acoelomates: No body cavity. Pseudocoelomates: False cavity. Coelomates: True body cavity.
What are the three germ layers, and what do they form?
Ectoderm: Skin, nervous system. Mesoderm: Muscles, bones, circulatory system. Endoderm: Digestive, respiratory systems.
What are Hox genes?
Regulatory genes that control body plan development in animals.
What are the three major clades of Bilaterian animals?
Lophotrochozoa: Mollusks/annelids. Ecdysozoa: Molting animals. Deuterostomia: Echinoderms/chordates.
Do sponges have true tissues?
No, they lack true tissues.
What are the functions of spicules, choanocytes, and amoebocytes in sponges?
Spicules: Support. Choanocytes: Create water flow, trap food. Amoebocytes: Transport nutrients, produce spicules.
What are the major body segments of arthropods?
Head, thorax, abdomen.
What are the four major classes of Phylum Mollusca?
Polyplacophora: Chitons. Gastropoda: Snails/slugs. Bivalvia: Clams/mussels. Cephalopoda: Squids/octopuses.
What are the four major embryonic characteristics of chordates?
Notochord, dorsal hollow nerve cord, pharyngeal slits, post-anal tail.
What invertebrates are also in Phylum Chordata?
Tunicates and lancelets.
What is a gnathostome?
A vertebrate with a jaw (e.g., sharks, bony fish, amphibians, reptiles, mammals).
What are the major classes of fishes?
Chondrichthyes: Cartilaginous fish. Actinopterygii: Ray-finned fish. Actinistia: Coelacanths. Dipnoi: Lungfish.
What are three major adaptations of bony fishes?
Operculum (gill protection), lateral line system (detects movement), swim bladder (buoyancy).
What are the three types of reproduction in animals?
Oviparous: Lays eggs. Ovoviviparous: Eggs hatch internally. Viviparous: Live birth.
What kind of animals are amniotes?
Reptiles, birds, and mammals.
What are the three major groups of mammals?
Monotremes: Egg-laying. Marsupials: Pouched. Eutherians: Placental.
What is the difference between endothermic and ectothermic animals?
Endothermic: Warm-blooded, regulate temperature internally. Ectothermic: Cold-blooded, depend on environment.
What characteristics make primates well-suited for arboreal life?
Opposable thumbs, binocular vision, flexible limbs.
What are the four extraembryonic membranes of amniotes?
Amnion: Cushions. Chorion: Gas exchange. Yolk sac: Nutrients. Allantois: Waste storage.
Which species of hominin lived alongside Homo sapiens and interbred?
Neanderthals (Homo neanderthalensis).
