Animal Kingdom L-4 Past Paper PDF

# Animal Kingdom ## Phylum - Platyhelminthes (Flatworm) * Body symmetry - Bilateral * Flattened body - Dorso ventrally flat * Triploblastic organism - Mesoderm originates * No cavity in body wall - Acoelomate * Most of the species are parasitic * Free living forms are found in Class Turbellaria * A...

# Animal Kingdom ## Phylum - Platyhelminthes (Flatworm) * Body symmetry - Bilateral * Flattened body - Dorso ventrally flat * Triploblastic organism - Mesoderm originates * No cavity in body wall - Acoelomate * Most of the species are parasitic * Free living forms are found in Class Turbellaria * Appearance of head - Cephalisation * Organ level of body organisation * Fertilisation is internal ### * Asexual Reproduction * Regeneration, as a method of reproduction ## Reproduction * Hermaphrodite (তা) * Monoecious (10) * Bisexual * Digestive system - Incomplete * Circulatory system - Absent * Development - Indirect * Larvas found in many species ## Excretory System * Primitive type of excretory cell that can absorb waste products present in body fluid * Protonephridia (10) * Flame Cell * Body is divided into Head, neck, tail * Head is also called Scolex * Contains sucker and Hooks * Each segment is called Proglottids * Body of flatworm in class Cestoda is segmented (Pseudometamerism) * Outer surface is segmented * Helps in absorbing digested food from a host body * Helps in attaching the worm to the wall of intestine * Each proglottids contain male and female sex organs * Fertilisation occurs inside each segment ## Fig: Tapeworm ## Proglottide with fertilised egg is released from the body * This process of shedding of Proglottids is called Apolysis. * Example: * Class * Cestoda : Tapeworm * Trematoda: Liverfluke * Inside * Pig * Cow * Inside * Tanea solium * Tanea saginata * Fasciola hepatica * Forms a spore in the muscles of these animals ## Infectious stage of Tapeworm is also called Cysticercus * From Snail and fish consumption * Consumption of meat * Infectious slage is passed to Human. ## Turbellaria : Planaria * Free living ## Aschelminthes): (Roundworm) * Body is circular in cross-section * Triploblastic organism * Coelom is present is not lined by Mesoderm - Pseudocoelomate * Bilaterally symmetrical body * Complete digestive System - Mouth and Anus Present ## Muscular * Digestive tract has more developed pharynx - Worm can generate moderate level of suction through its mouth. * Excretory system is represented by a (Tube) that collects waste from body fluid and release it to the outside of body. * Circulatory and Respiratory system absent * Organ level of body organisation * Nervous system is represented by 2 nerve rings and a ventral nerve cord. * Roundworms are sexually dimorphic - Male worms are smaller - Female worms are Longer * Dioecious/Unisexual * Outermost layer of body has a thick resistant cuticle ## Fertilisation - Internal ## Development - Direct or Indirect ## Most common examples: * Ascaris lumbricoides (Roundworm) * Wuchereria bancroftif(filariad worm) * Ancylostoma (Hookworm) ## Ascaris * causes Ascariasis ## W. bancrofti * causes Elephantiasis ## Through Contaminated food and water * (Rhabditifoom larva) ## Larva) * Microfilaria larva ## Culex mosquito (Vector) * Bites Human