Zoology Exam 4 Study (4)
What are examples of Organisms in the Phylum Hemichordata?
- Acorn Worm
What kind of Nerve Chords can Hemichordates have?
Ventral or Dorsal nerve chord
Hemichordates have a body with what?
Do Hemichordates have a Notochord?
No, They have a Buccal Diverticulum (or Stomochord)
Are Hemichordates Solitary or Colonial?
What do Hemichordates use for repiration?
Gill pores and Gill slits
What are the characteristics of Hemichordates?
- No Notochord
- They have a Stomochord (Buccal Diverticulum) that was mistaken for a Notochord
- They have a body with proboscis
- They have a Collar
- They have a Trunk
- Gill Slits
- Gill pores
- Some Have Dorsal Hollow Nerve Chord
- Some have Ventral Nerve Chord
- They can either be Solitary or Colonial.
What type of feeders are Hemichordates?
Suspension and Deposit.
Are Hemichordates Deuterostomes or protostomes?
What are the 5 Defining features of the Phylum Chordata?
- Notochord (Support Rod)
- Dorsal Hollow nerve cord
- Pharyngeal pouches (gill slits)
- Muscular Postanal tail
What can we say of the key defining features in Chordates?
They are all present at some time in development.
What are the subphyla of the phylum Chordata?
Name a genera of the Subphylum Cephalochordata.
What are some Characteristics of the Subphylum Cephalochordata?
- Segmented trunk musculature
- Larval features are retained in adults.
What are some examples of organisms in the subphylum Urochordata?
Tunicates and Salps
What are some characteristics of Urochordates?
- Closest relatives to craniates
- They have Chordate features in larvae, but lose it in adults.
What are Examples of organisms in the subphylum Craniata?
What is a characteristic of organisms in the subphylum Craniata?
They have larval features retained but modified in adults.
In Craniates, a Notochord is modified into what?
In Craniates, a Dorsal hollow nerve cord is modified into what?
A spinal Cord
In Craniates, An Endostyle is modified into what?
In Craniates, Pharyngeal gill slits are modified into what?
An extension of the spinal chord that extends beyond the animal's anus, that they may or may not have their entire life.
What are the key features of the subphylum craniata?
–Cranium (house brain & complex sensory organs)
–Neural crest and placodes
–Muscular pharynx and gut tube
In Craniates, What house the brain and complex sensory organs?
What type of skeleton do craniates posses?
What are the Chacteristics of the Neural crest?
–cells migrate from top of neural folds
–Forms cranium, parts of sense organs & sensory system in head and more
Forms cranium, parts of sense organs & sensory system in head and more
Ectodermal thickenings that form sense organs and nerves
The retention by adults of traits previously seen only in the young.
Gene clusters that Control development of body plan in all animals, They also Turn genes ‘on’ and ‘off’
What is a characteristic of Ancestral Craniates?
They were free swimming
Early jawless vertebrates
Jawless fishes that are not monophyletic
What is an example of an Agnatha.
What are some characteristics of a hagfish?
- Craniate, not vertebrate (no true vertebrae)
- No eyes, no fins, no scales
- Unusual reproduction
What are the Synapomorphies of Vertebrates?
- They have a Vertebrae around their Spinal cord and Notochord
- They have two Semicircular duct in their ear
What are the habitats of the jawless vetebrate Lamprey?
What are the Characteristics of the Jawless Vertebrate Lamprey?
- They are Marine or FW
- They have eyes, Fins, and No Scales
- Most are Parasitic
- They have an Ammocoete larva
What are the synapomorphies of the class Gnathostoma?
- They have Jaws
- They have three semicircular ducts in their ear
What did Jaws evolve from?
What periods did the Ancient Jawed Fishes live in?
The Silurian and Devonian
Which class of fish are within the Ancient Jawed Fishes?
- Class Placodermi
- Class Aconthodii
What are the Characteristics of the class Placodermi?
- Head shield
- neck joint
- no internal bones
What are the Characteristics of the class Acanthodii?
- close to bony fish
What are some examples of organisms in the class Chondrichthyes?
What are the synapomorphies of organisms in the class Chondrichthyes?
- cartilage skeleton
- placoid scales
- retain urea during Osmoregulation
- pelvic claspers in males
What structure is present in the male of Chondrichthyes?
What are Synapomorphies of Teleostomi?
- Bony endoskeleton
Class Actinopterygii are known to be what?
the most diverse group of vertebrates with 27,000 species
The Synapomorphies of Tetrapods are what?
Class Sarcopterygii are..?
Fleshy finned fishes.
What are some examples of the Class Sarcopterygii?
What are examples of Amphibians?
What are the Synapomorphies ( key features) of Amphibians?
- Reduced number of digits
- Bimodal life history
What si the Synapomorphy of Amniota?
Their Embryo is surrounded by membranes (e.g., amnion).
What are the synapomorphies (key features) of the class mammalia?
- Mammary glands
- Unique dentition
What is a characteristic of class Reptilia?
It is not Monophyletic.
What are some organisms in the class Reptilia?
- birds (Class Aves)