ANIMAL KINGDOM 3 Flashcards
meaning of chordata
The term chordata is derived from two words of Greek language ‘Chorda’ and ‘Ata’.
Meaning of ‘Chorda’ is ‘a thick string’ and meaning of ‘ata’ is ‘to have’ and over all
meaning of chordata is animals having notochord.
acraniata/protochordata
Exclusively marine.
*Pharyngial gill clefts are found throughout the life for respiration.
*Notochord is present in larval stages or persists throughout the life,
but skull, brain and vertebral column is absent in them.
*Notochord is not replaced by vertebral column, hence they are
chordate but not vertebrate.
*Protochordata is divided into two subphylum :-
1.Subphylum - Urochordata
2.Subphylum - Cephalochordata
explain urochordata/tunicata
All the adult members have test over their body, made up of tunicin which is just like
cellulose, hence these animals are also called tunicates.
All the members of this subphylum show “Retrogressive metamorphosis”. During this
metamorphosis, a well developed free swimming larva is changed into less developed
sessile adult. In these animals larval stage is more developed.
Notochord is present only in tail of tadpole larva. Tail is lost during metamorphosis.
Chordate character i.e. notochord found only in the tail region of tadpole larva
differentiate gnatha and ganthostomata
Agnatha
Jaws are absent
Notochord persistent, cartilaginous
vertebrae are found over the notochord.
Paired appendages are absent
Gnathostomata
Mouth is encircled by true jaws.
Vertebral column well developed.
Paired fins or limbs are present
2 classes of agnatha
A.Ostracodermi- All the members of this class are extinct. These were
freshwater fishes which were first vertebrates as well.
B.Cyclostomata- Circular Mouth
excretionof cyclostomata
-pronephric kidney
Anadromous Migration- Cyclostomes are marine but migrate for
spawning to fresh water. After spawning within few days they die.
Their larvae after metamorphosis, return to ocean.
explain features of superclass pisces
Study of fish → Icthyology (includes true fishes).
*Animals → Cold blooded (Poikilothermal) .
*Body → Stream lined divided into head, trunk and tail (neck absent).
*Super class Pisces is divided into three classes:-
A.Placodermi- Extinct
B.Chondrichthyes (Elasmobranchi)
C.Osteichthyes (Teleostomi)
amphibiia
Skin Moist, Smooth and scale less (Exception- Ichthyophis)
Frog → Mucous glands
Toad → Poisonous glands
Pigment cells → chromatophore for coloration →
Metachrosis
Digestive System Cloaca present
Acrodont (Teeth are attached superficially with jaws)
Respiration Lungs (Pulmonary)
Buccopharyngeal
Cutaneous respiration (Hibernation & Aestivation)
CirculationHeart is ventrally located, Myogenic
3 chambered→ 2 auricles + 1 ventricle
RBC → Nucleated & Biconvex
Excretion Larva → Aquatic → Ammonotelic
Adult → Terrestrial → Ureotelic
Mesonephric kidney → Loop of Henle absent
Nervous System Brain & Spinal cord
10 pair of cranial nerves
Sense Organs One pair of eyes
A tympanum represents the ear
Reproduction Unisexual & external fertilization (oviparous)
Development Indirect
reptiles
Skin Dry, cornified skin, epidermal scales or scutes.
Digestive System Complete & Extracellular
Snakes → Pleurodont → Teeth present on lateral
side of jaw bone.
Crocodile → Thecodont → Teeth present in bony
socket
Turtles → Teeth Absent
RespirationLungs (Pulmonary)
Circulation 3 chambered→ 2 auricles + 1 ventricle
Crocodile → 4 Chambered
Excretion Urecotelic
Metanephric Kidneys → Loop of Henle present
Nervous System Brain & Spinal cord
12 pair of cranial nerves
Sense Organs One pair of eyes
A tympanum represents the ear
Reproduction Unisexual, Internal fertilization
Oviparous & Ovoviviparous
Development Direct
aves
Skin Dry without glands
Presence of feathers
Uropygial or Preen or Oil gland →Base of the tail.
Flight adaptations Forelimbs modified to wings
Pneumatic Bones → Long bones are hollow with air
cavities
Digestive System Mouth is modified into beak
Teeth are absent
Crop and gizzard present
Cloaca present
RespirationLungs (Vascular)
Air sacs (Non vascular) → supplement respiration
Syrinx → Voice Box
Circulation Heart is 4 chambered
Excretion Urecotelic
Metanephric Kidneys → Loop of Henle present
Urinary bladder absent
Nervous System Brain & Spinal cord
12 pair of cranial nerves
Sense Organs Pecten is found in the eyes → Acute vision and
Telescopic vision
Reproduction Unisexual, Internal fertilization (oviparous)
Development Direct
in females , only left ovary is functional.
aves examples
Corvus (Crow), Columba (Pigeon), Psittacula (Parrot), Struthio (Ostrich), Pavo
(Peacock), Aptenodytes (Penguin), Neophron (Vulture),
mammalia
Exoskeleton Hair, nails, claws and horns
Endoskeleton Bones & Cartilage
Digestive System Complete
Cloaca absent (except Prototherians)
RespirationLungs
Circulation Heart is 4 chambered
RBC → Enucleated
Excretion Ureotelic
Metanephric Kidney
Nervous System Brain & Spinal cord
12 pair of cranial nerves
Corpus - callosum present
Sense Organs Eyes, nose, ear, skin, tongue
External ear or pinnae are present.
Reproduction Unisexual, Internal fertilization (Viviparous)
Development Direct
divisionof mmammila
(i) Prototheria:
egg laying mammals/ monotreme
eg: platypus
(ii)Metatheria:
marsupials/ pouch ed mammals
eg: kangaroo
(iii) Eutheria
True placental
mammals
*E.g. Humans, dogs,
cats
