Chapter 25- Chordata Flashcards
What are the 3 groups of Chordata and what animals do they include? What’s another name for tunicate? Lancelet?
- Chordata (all vertebrates)
- Tunicates (-urochordates) free swimming, sessile animals
- Lancelets (- cephalochordates) small, eel like animals
What structural features do chordates possess?
- Notochord (flexible skeletal support embedded in back)
- Hollow nerve chord
- Pharyngeal slits
- Tail
- Cranium
What are the 7 Chordata classes and their members?
- Agnatha-Jawless fish
- Chondrichthyes-cartilaginous fish, sharks, rays
- Osteichthyes-bony fish
- Amphibian- land and water animals
- Reptilia- snakes
- Aves-birds, feathers,
- Mammalian-hair, mammary glands, 3 middle ear bones
Describe the circulatory system of a fish. What are the chamber’s roles?
- Single loop
- Two chambers: atrium and ventricle
- Atrium-collects returning blood and pumps it to ventricle
- Ventricle-pumps it to gills and then rest of body
What are the 5 fish fins? What did jaws evolve from?
- Caudal fins (tail)
- Pectoral
- Pelvic
- Anal
- Dorsal
- They evolved from gill arches
What are the four fish classes and their members?
- Acanthodians- covered in spines-extinct
- Placoderms-heavily armored with bony plates-extinct
- Chondrichthyes-cartilaginous fish
- Osteichthyes- bony fish
What are the two classes of Chondrichthyes fish? What are 3 special adaptations to Chondrichthyes? What is one trait that is unique to bony fish?
- Holocephali-chimeras, ratfish-platelike grinding teeth
- Elasmobranchs-sharks, rays, skates
- Internal fertilization, lateral line, and electroreceptive cells
- The operculum
What trait allowed the evolution of land animals?
Lobed fins
What is a tetrapod? Amphibian? Adaptations to amphibians?
- A vertebrate animals with 4 limbs
- Animals that live both on land and in water
- Shoulders, hips, interlocking projections is spine, tongue, ears, tympanic membrane attached to stapes
What are 3 traits specific to amphibians? Describe the circulatory system?
- Gas exchange between skin, gills, or lungs
- 3 chambered heart with 2 atria and a ventricle
- Eggs have to be laid in moisture
- Pulmonary circuit-blood to skin and lungs: Systemic circuit-oxygenated blood to organs and back to heart
What changes does a tadpole experience in its metamorphosis to a frog?
- Gills to lungs
- Circulatory system is reorganized and blood and formed
- Carnivorous diet
Describe a salamander. Frog. Caecilian
- Do not have lungs, exchange gas through skin and mouth
- Bodies are adapted for jumping
- Legless, burrowing animals, hydrostatic body
What is an amniote? What is keratin? What is an amniotic egg?
- A vertebrate with thin, tough, membranous sac that encloses the embryo or fetus and all have keratin
- A protein that binds to lipids to form a hydrophobic layer, allows for less transpiration
- An egg filled with water that allows amphibians to lay eggs away from water
What is the placenta?
A membranous organ that develops in female mammals during pregnancy and carries nutrients from mother to embryo and carries away waste
What animals are considered amniotic?
Reptiles
Birds
Mammals
Why are tunicates more closely related to vertebrates than lancelets?
Tunicates and vertebrates both posses a group of embryo cells called the neural crest which develops into the nervous system, head, bones and teeth
