Phylum Chordata
Chordata is the animal
phylum with which everyone
is most intimately familiar,
since it includes humans
and other vertebrates.
However, not all chordates
are vertebrates.
Examples of CHORDATA
1.
2.
3.
4.
Urochordates
Tunicates
Cephalochordates
Amphioxus
Hemichoradtes
saw worms
Vertebrates
Characteristics of CHORDATA
All chordates have the following features at some point in their life (in
the case of humans and many other vertebrates, these features
may only be present in the embryo):
1.
2.
3.
4.
pharyngeal slits - a series of openings that connect
the inside of the throat to the outside of the "neck".
These are often, but not always, used as gills.
Dorsal nerve cord - a bundle of nerve fibers which
runs down the "back". It connects the brain with the
lateral muscles and other organs.
notochord - cartilaginous rod running underneath,
and supporting, the nerve cord.
post-anal tail - an extension of the body past the
anal opening.
Characteristics of Vertebrates
Vertebrates have the same characteristics as all other
chordates but they also have the additional and
distinguishing characteristic of having a back bone or
vertebral column.
Classes of Vertebrates
1.
2.
3.
4.
5.
6.
7.
Agnatha = Jawless
fish
Cartilaginous fish
Bony Fish
Amphibians
Reptiles
Birds
Mammals
Agnatha = Jawless fish
1.
2.
3.
Cartilaginous Skelton
No hinge in Jaw
Exposed gill slits
Cartilaginous Fish
1.
2.
3.
4.
5.
Cartilaginous Skelton
Hinge in Jaw
Tremendous chemo sensors
Scales
Internal Fertilization for sharks
Bony Fish
1.
2.
3.
4.
5.
6.
7.
Terminal mouth
Skeleton of bone for protection
Flap (operculum) covering the
gills
Swim bladder
The skin has many mucus
glands and is usually adorned
with dermal scales
Their jaws are well developed,
They have a two-chambered
heart
fertilization is usually external.
Amphibians
1.
2.
3.
4.
5.
6.
7.
First group to move to land
Land locomotion
Moist, glandular skin with no scales
Hearts have three chambers (two
auricles and one ventricle) and both
oxygenated and deoxygenated blood
pass through the Ventricle.
Respiration is by the skin, lining of the
mouth, gills, and/or lungs,
require water for reproduction
Fertilization may be internal or
external and most are oviparous
Amphibians
2 main groups
1.
2.
Tailed:
Tailless:
1 minor group

Legless
salamanders & newts
frogs & toads
Reptiles
1.
2.
3.
4.
5.
6.
7.
8.
Scaly skin to prevent water
loss
Concentrated urine reduces
water loss
Fertilization is internal
reducing reliance on water.
Leathery cover on eggs helps
prevent water loss
Lungs for respiration
Three chambered heart with
partially divided ventricle.
Crocodiles & Alligators have 4
chambered heart.
Some exhibit a degree of
endothermy
Reptiles
3 groups
1. Crocodiles & alligators
2. Turtles & Tortoises
3. Snakes & lizards


Poisonous snakes &
non-poisonous snakes
Poisonous snakes
come in 2 types
1.
2.
Neurotoxins
Hemotoxins
Exothermic Reptiles
AVES
1.
2.
3.
4.
5.
6.
7.
8.
Feathers
Very Concentrated urine
reduces water loss
Shelled eggs helps prevent
water loss & Protect
Four chambered heart
Endothermic (warm blooded)
Fertilization is internal
reducing reliance on water.
Hollow bones
Enlarged breast bone
Mammals
Three main groups
1.
Monotremes


2.
Lay eggs (External development)
Mammary Glands, hair
Marsupials (Kangaroo, Opossum)


3.
(spiny ant eater & duck billed Platypus)
Pouches (Partial internal development)
Mammary Glands, hair
Placental (most mammals)


Womb (full internal development)
Mammary Glands, hair
Mammals
Characteristics
1.
2.




hair
mammary glands
Their integument is complex and has many glands used for a variety of
purposes: thermoregulation and excretion (sweat glands), communication
(scent glands), care of the hair and skin (sebaceous oil glands), and for
feeding of the young (mammary glands).
They are thermic and have relatively high rates of metabolism. In keeping
with their higher metabolic rates, adaptations for efficient feeding include
heterodont teeth in most species and a secondary palate to separate the
respiratory and food passages (so they can breathe and chew at the same
time).
The circulatory systems are efficient, and they have a four-chambered heart
with separate pulmonary and systemic circulations.
Their brains are highly developed, fertilization is internal, and most have
placental attachment of the young.