-Cambrian explosion, diversification of plant and animals, Devonian period , seed plants appear, radiation of reptiles
reduction of gametophyte, seeds, heterospory, pollen, ovules
What are the 5 adaptations contributing to the success of seed plants as terrestrial organisms?
provides an embryo and food supply surrounded by protective coat
Why are seed an adaptation to living on land?
enhanced the ability of plants to survive and reproduce in diverse, terrestrial and dry environments
What is the importance of the evolution of seed production?
seeds are multicellular, more resistant, also has food supply and protective coat
What are advantages of seeds over spores?
The pollen tube discharges two sperm cell- one sperm fertilizes the egg- one sperm fuses with the female gametophyte producing a triploid cell develops into endosperm that nourishes developing embryo
one cotyledon, parallel veins, vascular tissue scattered, fibrous root system, pollen grain with one opening, flowers arranged in three
two cotyledon, netted veins, vascular tissue arranged in a ring, taproot root system, pollen grain with three openings, flowers arranged in multiples of four or five
chitin, hyphae, mycelium, heterotrophic absorption, dominant haploid stage
What are traits useful for differentiating plants, animals, and fungi?
What do fungi secrete to digest food outside its body to simpler compounds that it can absorb?
collared flagellate, heterotrophic, free living and sessile, unicellular and some colonial
What are characteristics of Choanoflagellates?
The increase of atmospheric oxygen resulted in a more active metabolism which resulted in?
embryonic development of tissues, no cell walls, nervous and muscle tissues, Hox genes
A shared derived traits in animals?
multicellular, digest internally, sexual reproduction, embryonic development of tissues, no cell walls, nervous and muscle tissues, Hox genes
What are characteristic of animals?
Tissues, Body symmetry, Germ layers,Body cavity, Embryological development,
The traditional animal phylogeny is based on shared derived anatomical traits?
same body plan for 50 mya, carnivores, tissues and simple nerves but no brain, asexual and sexual
used to Platyhelminthes, simple nervous system but no true brain, diverged before three main bilaterian clades, hermaphrodites
(flatworms) • 20,000 spp!
• flukes, planarians and tapeworms
• central nervous system = ganglia
• no circulatory system
• lots of parasites (like flukes and tapeworms)
• sexual and asexual (fission and some complex life cycles)
• tiny 0.05 - 2 mm
• feed on microorganisms
• specialized organ system and digestive tract
coelomates, open circulatory system, separate sexes or hermaphrodite, trochophore larvae, aquatic
(snails and slugs) - torsion- radula adapted for grazing or predation, foot adapted to move
squids, octopuses, chambered nautiluses- active predators, mantle reduced or lost, closed circulatory system
• 16,000 spp
• segmented worms
• earthworms, leeches
• closed circulatory
• mostly aquatic / some
• 25,000 spp
• roundworms (not segmented)
• found everywhere! - aquatic, soil, plant tissues, animal
tissues - predatory, decomposers, parasites
• no circulatory system (absorption!)
• separate sexes
• lots of parasites (like heartworm)
coelomates with open circulatory systems
• segmented bodies
• hard exoskeleton (chitin)
• jointed appendages
• well developed sensory organs
• most with complex internal organs
• 7,000 spp
• sessile or slow moving
• unique water vascular system
and tube feet
• sexual reproduction
• no brains
• filter feeders, predators,
notochord, dorsal hollow nerve chord, pharyngeal slits or clefts, muscular post anal tail
What are the four derived character states of Chordates?
• A longitudinal, flexible rod located between the
digestive tube and the nerve cord
• Provides skeletal support and a structure for muscles to
• In most vertebrates a jointed skeleton develops around
the ancestral notochord
dorsal, hollow nerve cord
•Develops in the vertebrate embryo from a plate of ectoderm that rolls
into a tube dorsal to the notochord
• In other animals the nerve cords are solid and usually ventral
• Develops into the central nervous system = brain and spinal cord
muscular post anal tail
non chordates have a digestive tract that extends nearly the whole length of the body and do not have a post anal tail, helps aquatic species swim, reduced during development in many groups
brain, eyes, skull, two cluster of Hox genes, neural crest, duplicated families, pharyngeal clefts, two chambered heart
What are shared derived traits for Craniates?
teeth, bones and cartilage of skull, inner layer of skin, neurons, sensory capsules
What does the neural crest give rise to craniate structures?
• Only 35 species
• Suspension-feeding larvae
• Adults parasitic
• No real jaw
• Cartilage skeleton
- including vertebrae
gametophyte is protected and nourished from environmental stresses
Why is the reduction of the gametophyte important advantage for terrestrial living?
the emergence of predator prey relationships
Explain the ecological cause of the Cambrian explosion?
What stage in embryonic development does a series of mitotic division with no cell growth occur?
What stage in embryonic development is there a multicellular hollow ball with specific regions that give rise to specific components?
What stage in embryonic development do layers of embryonic tissues are produced that will develop into adult body parts?
special regulatory genes that control the transformation of a zygote to a specific animal.That is they control the 'fate' of embryonic cells
less segmentation, fused segments, specialized appendages, variation from segment to segment
What is the Arthropod Evolution
ossified exoskeleton, maneuverable swimmers, lungs or lung derivatives, flattened bony scales
What are the characteristics of bony fishes?
four feet, separation of head, modification of pelvis for walking, loss of gills, ear drum
Shared derived traits of tetrapods?
rayed fin fishes, coelocanths, lungfishes, amphibians, reptiles, mammals
What phyla are considered the Osteichthyes?
sharks and ray, rayed fin fishes, coelocanths, lungfishes, amphibians, reptiles, mammals
What phyla are considered the Gnathostomes?
lampreys, sharks and ray, rayed fin fishes, coelocanths, lungfishes, amphibians, reptiles, mammals
What phyla are considered the Vertebrates?
Shared derived trait because the mineralized skeleton was a characteristic of its ancestor
Is Cartilaginous skeleton a ancestral or derived trait in Condrichthyes?
all animals share a common ancestor, sponges are basal animals, eumetazoa is a clade of animals with true tissue,most animals belong to the clade Bilateria, Vertebrates and some other phyla belong to the clade Deuterostomia
What are the 5 points of agreement between the morphological and molecular trees?
armored with mineralized bones, muscular pharynx, inner ear, paired fins
Characteristics of jawless armored vertebrates
microsporangium, microspore, pollen grain, male gametophyte, sperm
Outline the route from microsporangium to sperm.
ovule, megasporangium, megaspore, female gametophyte, egg
Outline the route from ovule to the egg....
different nuclei...the fused mycelium contain coexisting genetically different nuclei- result of plasmogamy
All animals share common ancestor, sponges basal, eumetozoa, bilateria, dueterostome
What are the points of agreements between the molecular and traditional phylogenetic tree?