Unit 02: Animal Diversity Flashcards
List the heterotrophs.
Animals, fungi
What type of lifecycle do animals go through?
Diplontic
What is the outmost germ layer?
Ectoderm
What is the innermost germ layer?
Endotherm
What organisms have a third germ layer and what is it called?
Bilaterally symmetrical animals, also known as triploblasts. Called the mesoderm.
What two groupings of eukaryotes evolved from the most ancient ancestor?
Parazoa and Eumetazoa, no membrane and yes membrane.
What group is the most common ancestor of animals shared with?
Choanoflagellates
What is the earliest descendant of animals?
Phyla Porifera, also known as sponges.
What phylum is Parazoa?
Porifera, as they have no tissues and no radial symmetry.
What phylum did radial symmetry evolve from?
Cnidaria
In what type of animals does the blastula folding in result in the development of the mouth first.
Protostomes.
In what type of animals does the blastula folding in result in the development of the anus first.
Deuterostomes
What is the difference between triploblastic and diploblastic animals?
The presence of the mesoderm (present in triploblastic animals)
What are the two basic body shapes of the Cnidaria phylum?
Polyp and medusa
What are some characteristics of the polyp body shape?
- Cylindrical body
- Mouth facing up
- Aboral side moves body
What are some characteristics of the medusa body shape?
- Mouth and tentacles point downwards
- Moves freely in water
What animals have a polyp body shape?
Anemone and corals, also called the Anthozoan clade within the phylum Cnidaria
What animals have a medusa body shape?
Jellyfish and hydrozoans, also called the Medusozoan clade within the phylum Cnidaria
What germ layer forms the digestive tract, liver and lungs?
Endoderm
What type of evolution are grades evidence for?
Convergent
What is the difference between eucoelomates, pseudocoelomates and acoelomates
Eu - Cavity lined with mesoderm
Pseudo - Cavity partly lined by mesoderm
A - Cavities not completely formed, therefore no space between layers.
What are the characteristics of bilateral symmetry?
- Dorsal (top) and ventral (bottom) sides
- Right and left side
- Anterior and posterior ends
- Cephalization
What is cephalization?
Concentration of sensory nerves at an anterior end of the body.
What type of evolution do clades provide evidence for?
Divergent
What does the mesoderm end up forming?
Muscles and most inner organs
Does cephalization occur in radially or bilaterally symmetric animals?
Bilaterally symmetrical
What are some animals in phylum Echinodermata and some key characteristics?
Starfish, sea urchins
Characteristics:
Water-vascular system, tube feet, pentaradial symmetry
What are the echinoderm clades and what species are a part of each clade?
Asteroidea - starfish
Echinoidea - Sea urchins, sand dollars
Holothuroidea - Sea cucumbers
What is segmentation? In what phyla does segmentation occur?
Body made of identical repeating units. Occurs in Chordates, Annelida and Arthropoda
What are the three major clades of chordates?
Vertebrata, Urochordata, Cephalochordata
What are the four major characteristics of chordates?
Notochord, dorsal hollow nerve cord, phalangeal gills/slits, post-anal tail
What are the most basal chordates?
Clade Cephalochordata
Describe the chordate characteristics present in embryonic tunics (Urochordata) VS. mature
Embryonic - has all characteristics
Mature - only retains gills
What derived characteristics do the clade Vertebrata have?
Vertebrae enclosing spinal cord, elaborate skulls, and fin rays
What are the most basal vertebrates?
Jawless fish, ex. lampreys and hagfish
Why are jaws hypothesized to have evolved?
To support pharyngeal slits
What is the derived character of the Gnathostomata clade? What animals does it include?
Jaws
Sharks, ray finned fishes, lobe finned fishes, amphibians, reptiles, birds, mammals
What animals make up the Osteichthyes clade?
All fishes with jaws.
Ray finned fishes + lobe finned fishes
What type of fish did tetrapods evolve from?
Lobe finned fishes
The clade amniota includes what animals?
Mammals, reptiles and birds
What is the derived character of the clade amniota?
Amniotic egg with 4 extraembryonic membranes.
What are the 4 membranes of the amniotic egg and their functions?
Amnion - Shock Absorber
Chorion - Gas Exchange
Yolk Sac - Provides Nutrients
Allantois - Waste Storage
What are the 2 derived characters of mammals?
Hair and production of milk.
What are the three clades of mammals?
Monotremes, marsupials, and eutherials.
What differentiates monotremes from other mammals?
They lay eggs
What differentiates marsupials from eutherials?
Marsupials have shorter digestive stage where “joey” crawls into mothers pouch to continue development.
Eutherials have a longer gestation period, baby comes out more developed.
What animal clade has the widest range of body forms?
Lophotrochozoa
List the common structures of the phylum Mollusca and their functions.
Muscular foot - Movement, prey capture
Mantle - Water filled space with gills, anus, execratory pores. Produces shell.
Radula - Tongue-like, captures food
Visceral Mass - Holds internal organs
What are the 4 molluscan clades?
Gastropods - snails, slugs
Bivalvia - clams, oysters
Polyplacophora - many piece shells
Cephalopoda - squids, octopus
Describe cleavage in protostome development
Spiral and determinate
Describe cleavage in deuterostome development
Radial and indeterminate. Cell divisions at right angles to each other.
What type of animals are in phylum Annelida?
Segmented worms
What are the two clades of phylum Annelida and what are their differences?
Errantia - Mobile segmented worms. Have whisker like structures called parapodia that help with locomotion. Mostly marine
Sedentaria - Less mobile segmented worms (earth worm, leeches, etc.). Can be marine or sedimentary.
Describe some characteristics of phylum Brachiopoda.
- Attached to the sea floor.
- Right and left sides are symmetrical.
What are the differences between Brachiopoda clade Inarticulata and Articulata?
Inarticulata - Small/ no hinge, complete gut
Articulata - Large hinge, incomplete gut (poop comes thru mouth)
What are Unikonts? What are some organisms that fall into this group?
One of four Eukarya supergroups. Contains animals, fungi, slime molds, choanoflagellates.
Split into 2 clades, Amoebozoans and Opisthokonts
What are some organisms included in the clade Amoebozoans within the Unikonta supergroup.
Slime moulds, amoeba
What are some organisms included in the clade Opisthokonts within the Unikonta supergroup.
Animals, fungi, choanoflagellates
Describe characteristics of the Phylum Porifera and list some organisms belonging to the phylum.
Sponges with no true tissues, therefore parazoans. Asymmetrical, and thought to be the most basal phylum of animals.
They are totipotent, meaning they will regenerate any of their cells/change one type of cell into another.
Describe characteristics of the Phylum Cnidaria and list some organisms belonging to the phylum.
Dipoblastic, radially symmetrical organisms. Tissue layers are thought to have evolved from Cnidaria.
Two body shapes -
Polyp - more sessile with mouth facing up. ex. anemones and corals
Medusa - mouth down, can move freely in water. ex. jellyfish and hydrozoans
