This document discusses characteristics of the animal kingdom phylum Vertebrata and class Pisces. It describes how vertebrates possess a notochord that is replaced by bone or cartilage, and have features like a heart, kidneys and paired appendages. It outlines characteristics of jawless fish class Cyclostomata and cartilaginous fish class Chondrichthyes. Finally, it provides details about bony fish class Osteichthyes, including examples of marine and freshwater fish.

2. Chapter 4
Animal Kingdom
Phylum Vertebrata and Class Pisces
Lecture no.5

3. Vertebrata

4. Phylum Chordata
Sub-Phylum
urochordata
Sub-Phylum
Cephalochordata
Sub-phylum
Vertebrata

5. Vertebrata
 These are true chordates
 The members of subphylum vertebrata possess
notochord during the embryonic period
 The notochord is replaced by a cartilaginous or bony
vertebral column in the Adult.
 All vertebrates are chordates but all chordates are
not vertebrates.
 Vertebrates have a ventral muscular heart with two,
three or four chambers, kidneys for excretion and
osmoregulation and paired appendages which may
be fins or limbs.

7. Class Cyclostomata
 They are not true fish
 Jaw-less fish
 They are ectoparasite on some fishes
 They get stuck on fish and suck nutrition
 They have an elongated body bearing 6-15
pairs of gill slits for respiration.
 Cyclostomes have a sucking and circular
mouth without jaws

8.  Their body is devoid of scales and paired
fins.
 Cranium and vertebral column are
cartilaginous.
 Circulation is of closed type.
 Cyclostomes are marine but migrate for
spawning to fresh water. This type of
migration is called Anadromous migration
 After spawning, within a few days, they
die. Their larvae, after metamorphosis,
return to the ocean.
Examples: Petromyzon (Lamprey) and Myxine
(Hagfish).
Source NCERT

9. Pisces

10. Characteristic features of Fish
 Body-Streamlined body
 Fins-helps them in movement
 The various fins are:
 Caudal fin(1)
 Pectoral fin(2)
 Dorsal fin(1)
 Pelvic fin(2)
 Anal fin(1)

11. Pisces
Chondriochthyes Osteichthyes

12. Class Condrichthyes
 They are marine animals with streamlined body and
have cartilaginous endoskeleton .
 Mouth is located ventrally.
 Notochord is persistent throughout life.
 Gill slits are separate and without operculum (gill
cover).
 The skin is tough, containing minute placoid scales.
 Teeth are modified placoid scales which are
backwardly directed.

13.  Their jaws are very powerful. These animals are
predaceous.
 Due to the absence of air bladder, they have to swim
constantly to avoid sinking.
 Heart is two-chambered (one auricle and one
ventricle).
 Some of them have electric organs (e.g., Torpedo)
and some possess poison sting (e.g., Trygon).
 They are cold-blooded (poikilothermous) animals,
i.e., they lack the capacity to regulate their body
temperature.
Source NCERT

14. Reproduction
 Sexes are separate.
 In males pelvic fins bear claspers.
 Fertilization- internal fertilisation and many
of them are viviparous.
 Examples: Scoliodon (Dog fish), Pristis (Saw
fish), Carcharodon (Great white shark),
Trygon (Sting ray).

16. Class Osteichythes
 It includes both marine and fresh water fishes bony
endoskeleton.
 Their body is streamlined.
 Mouth is mostly terminal .
 They have 4 pairs of gills which are covered by an
operculum on each side.
 Skin is covered with cycloid/ctenoid scales.
 Air bladder is present which regulates buoyancy.
(Angel fish)

17.  Heart is two chambered (one auricle and one
ventricle).
 They are cold-blooded animals.
 Sexes are separate.
 Fertilization is usually external.
 They are mostly oviparous and development is
direct.
 Examples: Marine – Exocoetus (Flying fish),
Hippocampus (Sea horse); Freshwater – Labeo
(Rohu), Catla (Katla), Clarias (Magur); Aquarium –
Betta (Fighting fish), Pterophyllum
Source NCERT

19. MCQ
Q1.Osteichthyes belongs to
(a) class amphibia
(b) super class pisces
(c) super class tetrapoda
(d) division agnatha
Ans:(b) super class pisces

20. Q2.Water-Vascular system is found in
(a) Sea-anemone
(b) Sea-pen
(c) Sea-cucumber
(d) Sea-horse
Ans:(c) Sea-cucumber

21. Q3.Sharks, skates, and rays are also called ______fishes.
(a) Jawless
(b) Bony
(c) Cartilaginous
(d) Freshwater
Ans:(c) Cartilaginous

22. Q4.Which one of the following is NOT a characteristic of phylum
Annelida?
(a) Ventral nerve cord
(b) Closed circulatory system
(c) Segmentation
(d) Pseudocoelom
Ans:(d) Pseudocoelom

23. Q5.Excretion in flatworms occurs by
(a)Nephridia
(b)Flame cells
(c)Malpighian tubules
(d)Green glands
Ans: (b) Flame cells