Chapter 29: Vertebrates

THIS SHIT IS LONG AS FUCK

What is the most recognized phylum of all Kingdom Animalia?

Chordata

What is the body plan of Chordata?

Bilateral triploblastic eucoelomate deuterostomes

What is the germ layer of Chordata?

Triploblastic eucoelomates

What type of digestive system do chordata have?

Complete

What excretory organ do all Chordata have?

Kidneys

What nervous organ do all Chordata have?

Brain with central nervous system

What are types of respiratory systems Chordata have?

Gills, lungs, skin

What are the 5 defining characteristics of all Vertebrates?

Notochord, hollow dorsal nerve cord, pharyngeal slits, post-anal tail, endostyle/thyroid gland

What is the notochord?

Flexible, rod structure derived from mesoderm tissue

Where can the notochord be found?

Dorsal to the digestive tube and ventral to the nerve cord

What does the notochord do?

Provides rigid support and muscle attachment sites

When during a chordates life can notochord’s be found?

Embryonic stage for ALL and adult stages for SOME

In true vertebrates, notochords are replaced with the ___

Spine (vertebral column)

How is the hollow dorsal nerve cord made?

From ectoderm

Where can the hollow dorsal nerve cord be found?

Dorsal to the notochord

What does the hollow dorsal nerve cord develop into?

Brain and spinal cord (central nervous system)

What are the pharyngeal slits?

Openings to pharynx, allowing connection between external environment and pharynx

How do the pharyngeal slits work in aquatic vertebrate fishes?

Water enters through mouth when feeding and exits through the slits

What do pharyngeal slits develop into in aquatic vertebrate fishes?

In jawless fishes: gill support

In Jawed fishes: jaw support

What do pharyngeal slits develop into in land vertebrates?

Parts of the ear, tonsils and thymus

What is the post-anal tail?

Posterior tail that extends beyond the anus

What does the post-anal tail contain?

Skeletal and muscular components

In aquatic species, what are post-anal tails used for?

Locomotion

In terrestrial species, what are post-anal tails used for?

Balance

What are post-anal tails reduced to in humans and apes?

Coccyx

What is the endostyle/thyroid gland?

Mucus producing tissue on the floor of the pharynx

What do endostyle/thyroid gland develop into in most vertebrates?

Thyroid gland

The two chordate clades that are invertebrates are extremely ____ chordates

Primitive

What are the two invertebrate chordates?

Cephalochordata and Urochordata

What’s an example of cephalochordata?

Lancelets

What’s an example of Urochordata?

Tunicates (sea squirts)

How many defining characteristics do urochordata larvae have?

All five

How many defining characteristics do urochordata adults have?

Two; pharyngeal slits and endostyle only

What is the largest group of Chordata?

Subphylum Vertebrata (Craniata)

What is the cranium?

Bony or cartilaginous or ligamentous structure surrounding brain, includes jaw structures and facial structures

Bilateral animals almost always have a head but not all have a…

Cranium

Do vertebrata have all defining characteristics of chordata?

Yes

What’s a new adaptation vertebrata have?

Vertebral column (spine)

What is a vertebral column?

Irregularly shaped bones joined together to form a backbone

What happens to the notochord as vertebrata grow up?

Replaced by vertebral segments

What are agnathostomes?

Animals without a jaw

What are gnathostomes?

Animals with a jaw

What are the two classes of Agnathostomes?

Myxini and Petromyzontidae

What are gnathostomes divided into?

Fishes and tetrapods

What animals are tetrapods?

Amphibians, reptiles, birds and mammals

What are the two groups of tetrapods?

Amphibians and amniotes

What are amniotes?

Animals with eggs that contain extraembryonic membranes

What are the amniote contents?

Yolk, amnion, chlorion, allantois

Are amniotes adapted to terrestrial life or aquatic life?

Terrestrial life

What are examples of animals with amniotes?

Mammals, birds and reptiles

What is the biggest number of species of subphylum chordata?

Fishes

Who are considered early vertebrates that lived in the sea?

Fishes

Are fishes active feeders or sessile feeders?

Active feeders

What are the two groups of fish?

Agnathastomes and gnathostomes

What are examples of agnathastomes?

Petromyzontidae (lamprey) and Myxini (hagfish)

Who’s the older species between agnathastomes and gnathastomes?

Agnathastomes (550mya)

What do agnathastomes DON’T have?

Hinged jaw, paired lateral fins, scales, internal ossification

What do agnathastomes have?

Cranium

Myxini are ___ while Petromyzontidae are ___

Scavengers; parasitic

How do Myxini sense?

Sensory barbels around mouth

What type of cranium do myxini have?

Cartilaginous

What do Myxini use for body support?

Notochord

What are Myxini teeth made of?

Keratin and have a cartilage base

How do Myxini feed themselves?

Rasp pieces of food from dead animals

What do Petromyzontidae have?

Eyes, cerebellum, and cranium

What type of vertebrae do Petromyzontidae have?

Simple vertebrae

How do Petromyzontidae eat?

Suction mouth with rasping tongue

Petromyzontidae are ___

Ectoparasites

Gnathostomes have a true, ___ jaw

Hinged

What does a hinge jaw help with?

Allows for grasping and tearing food

What fins do Gnathostomes have?

Paired pectoral fins and paired pelvic fins

What do the new fins Gnathostomes have help with?

Accurate, nimble movement

Both a true hinged jaw and newly developed fins allow for Gnathostomes to become…

Active feeders

What are the two classes of Gnathostomes?

Chondrichthyes and Osteichthyes

What are Chondrichthyes?

Cartilaginous jawed fish

What are examples of Chondrichthyes?

Sharks, rays, and skates

Chondrichthyes are mostly ____ species

Marine

What type of feeders are chondrichthyes?

Carnivorous but some filter feeders

What type of skin do most Chondrichthyes have?

Abrasive skin covered with placoid scales

Chondrichthyes have a well-developed ____ system

Sensory

What does the Ampullae of Lorenzini help with in Chondrichthyes?

Detects electromagnetic fields

What does a lateral line do for Chondrichthyes?

Detects vibrations in water

What is the general body shapes for Chondrichthyes?

Dorsolaterally flattened, unequally sized fins

How do Chondrichthyes breathe?

Using gills

What are the respiratory organs for most aquatic animals?

Gills

What are gills?

Thin tissue filaments with extensive folding

What does the increased surface area from gills help with?

Ensures enough oxygen can be absorbed from oxygen-poor water

What is diffusion?

Particles move from high concentration to low concentration

How does oxygen go into blood?

Oxygen-poor blood flows countercurrent to water flow across gills (oxygen diffuses from water to blood)

What is the Chondrichthyes reproduction like?

Sexual reproduction with internal fertilization

What does viviparous mean?

Egg sac with embryo attaches to mother’s oviduct and embryo gets nutrition from another (live birth)

What does oviparous mean?

Lay eggs that hatch outside mother’s body, egg covered in leathery egg case, nutrition from egg yolk

What does ovoviviparous mean?

Fertilized egg develops inside mother, hatch in utero then born alive

What are Osteichthyes?

Bone jawed fish with true osseous bones, covered in overlapping scales

Where can Osteichthyes live?

Marine and freshwater

What kind of ‘vous’ are Osteichthyes?

Carnivorous, herbivorous, omnivorous

How do Osteichthyes breathe?

Gills

How do Osteichthyes control buoyancy?

Swim bladder

Osteichthyes have a well-developed ___ system

Sensory

What do Osteichthyes use a lateral line for?

Detect vibration in water