Post on 30-Dec-2015
transcript
IntroductionAll vertebrates are
Found within Phylum Chordata; Subphylum Vertebrata
DeuterostomesCoelomatesBilateral symmetricalHave an endoskeletonHave a closed circulatory systemHave a ventral heart
Introduction IIDuring the lifespan of chordates, they have a
notochord which serves as a flexible supporting rod.
Chordates have a single dorsal tubular(hollow) nerve cord.
All chordates have pharyngeal gill siltsIn some species, the gill slits are only found in
the embryosMOST chordates have a muscular postanal
tail.
Invertebrates vs. VertebratesHow are the two invertebrate subphyla of
chordates related to the vertebrate chordates?• Animals in the Subphylum Vertebrata retain
the characteristics of the other chordates.• However, many of the additional features that
separate the vertebrates from the other chordates are associated with a larger size and a mobile lifestyle.
• A major additional feature is the head Chordates with a head are known as craniates
Phylum ChordataPreviously covered from Phylum Chordata
were the two subphyla of invertebratesTunicatesLancelets
This packet will investigate SOME of the remaining organisms of this vast and wide phylum.
Phylum ChordataSubphylym VertebrataClass AgnathaInclude the lampreys
and hagfishes.Both are scales,
elongate fish without jaws or paired fins
Hagfish are marine scavengers
Lampreys are found in freshwater or marine habitats and include ectoparasitic species.
Class ChondrichthyesIncludes sharks, rays
and skatesCartilaginous fish have 5
– 7 pairs of gills and rely on swimming to force water
Sharks, and their relatives, have paired fins and placoid scales.Sharks may be
oviparous, ovoviviparous or viviparous.
Class OsteichthyesThis class is the most
speciose of the vertebrate classes.
Skeleton is composed of bone and is covered with overlapping flexible scales
Oviparous and produce a prodicious number of eggs.
Class Amphibia Include frogs, toads and
salamanders. Some members lack tails
Toads & frogs Some members lack legs
Tropical caecilians The larvae of toads and frogs are
aquatic Some salamanders undergo
neoteny. Retention of juvenile
characteristics in the adults of a species, as among certain amphibians. Reflect back to past genetics
packet. Adult amphibians rely heavily on
cutaneous respiration The amphibian hear has three
chambers (a atria and 1 ventricle) that allows a partially separated pulmonary and systemic circulation
Class Reptilia Includes turtles, lizards, snakes and
alligators Terrestrial animals that do not rely on
reproduce Dinosaurs are thought to be reptiles.
Became extinct at some point in earth’s history
Bodies covered in dry scales to prevent cutansous respiration
Lungs are more efficient than amphibians.
Waste is excreted in the form of uric acid
Reduces water loss Ectothermic organisms—similar to fish
and amphibians Most are carnivores Snakes have unusual adaptations for
efficient predation Chemical and temperature senses Produce toxins
Class Aves [ey-veez]The anterior appendages of
birds are winds and MOST birds do fly.
In order to fly, birds have skeletal reduction, efficient lungs, a four chambered heart, endothermy and frequent voiding of wastes.
Birds eat high energy foods to maintain a high metabolic rate.
The nervous system is cell developed Sight and hearing
Display complex social behaviors, vocalizations and territorial behaviors.
MammalsMammals are characterized by hair and mammary
glands.Mammals have specializations in dentition, a
diaphragm to aid in respiration, endothermy and a four chambered heart.
The nervous system, particularly the cerebrum, is quite advanced.
Fertilization is always internal and nearly all mammals are viviparous
Most mammals are placentalThe limbs are adapted for diverse forms of locomotion
MonotremesSubclass PrototheriaMammals that lay
eggsInclude the duck-
billed platypus and spiny anteater (echidna).
When the young hatch, they feed on the milk produced by the mammary glands.
MarsupialsSubclass MetatheriaPouched animalsInclude kangaroos,
koalas and opossumsMost common in
Australia
Placental MammalsSubclass EutheriaMammals that
complete embryonic development within the mother.
The most common form of mammals.
There is a placental connection between the embryo and the mother in the uterus.