RBSE Class 11 Biology Notes Chapter 4 Animal Kingdom

These comprehensive RBSE Class 11 Biology Notes Chapter 4 Animal Kingdom will give a brief overview of all the concepts.

RBSE Class 11 Biology Chapter 4 Notes Animal Kingdom

→ Porifera includes multicellular animals which exhibit cellular level of organisation and have characteristic flagellated choanocytes.

→ The coelenterates have tentacles and bear cnidoblasts. They are mostly aquatic, sessile or free-floating.

→ The ctenophores are marine animals with comb plates.

→ The platyhelminthes have flat body and exhibit bilateral symmetry. The parasitic forms show distinct suckers and hooks.

→ Aschelminthes are pseudocoelomates and include parasitic as well as non-parasitic round worms.

→ Annelids are metamerically segmented animals with a true coelom.

→ The arthropods are the most abundant group of animals characterised by the presence of jointed appendages.

 

→ The molluscs have a soft body surrounded by an external calcareous shell. The body is covered with external skeleton made of chitin.

→ The echinoderms possess a spiny skin. Their most distinctive feature is the presence of water vascular system.

→ The hemichordates are a small group of worm-like marine animals. They have a cylindrical body with proboscis, collar and trunk.

→ Phylum Chordata includes animals which possess a notochord either throughout or during early embryonic life. Other common features observed in the chordates are the dorsal, hollow nerve cord and paired pharyngeal gill slits.

→ Some of the vertebrates do not possess jaws (Agnatha) whereas most of them possess jaws (Gnathostomata).

→ Agnatha is represented by the class, Cyclostomata. They are the most primitive chordates and are ectoparasites on fishes.

→ Gnathostomata has two super classes, Pisces and Tetrapoda.

→ Classes Chondrichthyes and Osteichthyes bear fins for locomotion and are grouped under Pisces. The Chondrichthyes are fishes with cartilaginous endoskeleton and are marine.

→ Classes Amphibia, Reptilia, Aves and Mammalia have two pairs of limbs and are thus grouped under Tetrapoda.

→ The amphibians have adapted.to five both on land and water.

→ Reptiles are characterised by the presence of dry and comified skin. Limbs are absent in snakes.

→ Fishes, amphibians and reptiles are poikilothermous (cold-blooded).

→ Aves are warm-blooded animals with feathers on their bodies and forelimbs modified into wings for flying. Hind limbs are adapted for walking, swimming, perching or clasping.

→ The unique features of mammals are the presence of mammary glands and hairs on the skin. They commonly exhibit viviparity.

→ Aboral: In a direction away from the mouth; the part of the body opposite the mouth.

→ Acellular; Without cellular organisation.

→ Acoelomate: Animals without coelom.

→ Alimentary canal: The entire digestive tube (mouth, oesophagus, stomach and intestine) collectively.

→ Alternation of generation: Alternate succession of sexual and asexual generation in the life.

→ Amphibians: A group of vertebrates including frogs, salamanders and caecilians.

→ Anatomy: Study of the structure of animal and plants.

→ Antenna: The second cephalic appendage of copepods and branchiurans.

→ Antennule: The first cephalic appendage of copepods and branchiurans.

→ Anterior: Forward-moving end of animal.

→ Anticoagulating: Substance that prevents the coagulation of blood.    ,

→ Anticoagulin: An anticoagulant substance.

→ Anus: posterior opening of the digestive tract.

→ Apopyle: Pore leading from the chamber into the central cavity in sponge.

→ Appendage: A movable projecting part of the body.

→ Appendages: Portion of body that projects and has a free end such as limbs.

→ Aquaculture: The growing of aquatic organisms for human needs, this includes fish farming.

→ Aquatic: Found in water.

→ Arms: Long, flexible mobile limbs - usually containing a feeding groove.

→ Arthropoda: An invertebrate animal. having an exoskeleton, a segmented body, and jointed appendages.

→ Asymmetry: Condition in which opposite sides of an animal are not alike, without symmetry.

→ Benthic: Living on the sea bottom.

→ Bilateral symmetry: The arrangement of the body parts so that the right and left halves are mirror images of each other. 

→ Biradial symmetry: Condition in which an animal has radially arranged parts that lay half on one side and half on other side of a median longitudinal plane, e.g. Ctenophora.

→ Calcareous: Composed mostly of calcium carbonate or lime.

→ Capillary: The smallest blood vessels, just big enough for passage of red blood cells.

→ Chelicera: A pair of pincer-like head appendages of arachinids.

→ Chemo-receptors: Organs or neuron sensitive to specific chemical changes.

→ Chitin: A complex organic substance or a polysaccharide protein, forming the exoskeleton of arthropods and some other animals.

→ Choana: Internal opening of the nasal passage in the roof of the mouth (plural- choanae).

→ Choanocyte: Flagellated collar cells found in sponges.

→ Chondricthyan: A member of the class chondricthyes, cartilagenous fishes. Living fish in the class are the sharks and rays.

→ Chordata: Phylum of animals distinguished by their possession of a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail at some point during their , development.

→ Cilia: Hair like projection.

→ Clitellum: A thickened glandular portion of the body of an earthworm or other annelid, used in the formation of cocoon.

→ Cloaca: The common chamber into which the intestinal, urinary and reproductive duct discharge.

→ Coelenterata: Phylum (Cnidoblast structures).

→ Coelom: Body cavity lined with tissue of mesodermal origins in which the digestive and other organs lie.

→ Coelom: The body cavity lined with the tissue of mesodermal origin in which the digestive and other organs lie,

→ Coelomate: Coelomate animals or Coelomata (also known as eucoelomates - "true coelom") have a fluid filled body cavity called a coelom.

→ Collar: A distinct body region between the proboscis and the trunk that is attached to the proboscis on a medio-dorsal stalk. The ventral mouth opens anterior to the collar.

→ Colony: Group of individuls.

→ Columnar epithelial cells: are epithelial cells whose heights are at least four times their width.

→ Dioecious: having the male and female reproductive organs in separate individual.
 
→ Diploblastic: Derived from two embryonic germ layer, ectoderm and endoderm.

→ Direct development: Development to an adult body plan without an intervening larval stage.

→ Echinoderm: Member of a phylum of marine invertebrates comprising echinoids (sea urchins), asteroids (sea stars), crinoids (sea lillies), holothuroids (sea cucumbers) and ophiuroids (brittle stars).

→ Ectoderm: The outer of the three germ layers of the embryo.

→ Embryo: Young animal that is passing through its developmental stages.

→ Exoskeleton: A supporting structure on the outside of an animal body. The skeleton of an invertebrate is usually an exoskeleton.    .

→ Fertilization: Union of a male gamete (sperm) with a female gamete (ovum) to give an egg, or zygote,

→ Freshwater: Water containing less than 0.5% salts,

→ Fringing reefs: Coral ridge build up from ocean bottom.

→ Habitat: Physical area of the occurence of an animal species.

→ Haemocoelomic: A body cavity (as in arthropods or some molluscs) that normally contains blood and functions as part of the circulatory system.

→ Haemoglobin: is the protein molecule in red blood cells that carries oxygen from the lungs to the body's tissues and returns carbon dioxide from the tissues back to the lungs.

→ Haemocoel: Coelom filled with blood.

→ Herbivore: Feeding on vegetation.

→ Histology: The study of cellular and sub-cellular view of tissue, in other words the microscopic view, sf: Indirect development: Development to an adult via a distinct larval form.

→ Internal fertilization: The fusion of the male and female gametes occurs within the female's reproductive tract.

→ Mantle: A fleshy layer that secretes the shell of the mollusc.

→ Mantle cavity: The space between the mantle and the visceral mass.

→ Mesogloea: Non-cellular jelly like substance lying between the ectoderm and endoderm.

→ Mollusca: Non-segmented, schizocoelomate phylum, sf: Monoecious: Having both male and female reproductive organs.

→ Mduthparts: The group of appendages near the mouth which are involved in feeding, comprising the paired mandibles, maxillules, maxillas, and maxillipeds. 

→ Nematocysts: One of the stinging capsules found in the coelenterates.

→ Nephridla: is an invertebrate organ which occurs in pairs and performs a function similar to the vertebrate kidney.

→ Nephridium: tubular excretory structure characteristic of many invertebrates, Such as the animal.

→ Nerve cord: cord of neuron and ganglia forming part of a central nervous system.

→ Notochord: An embryonic rod-like structure that is located on the dorsal part of the developing animal and is essential for initiating the differentiation of the adult nervous system.

→ Operculum: Calcareous plate formed by cuticular secretion of the glandular cells of the animal foot.

→ Oral valve: Fish that have a respiratory pump have flaps behind each lip that act as a one way valve when the mouth is closed, preventing back flow of water out the mouth. Similarly, the opercula have a flap on the rear that seals the opercular opening during opercular expansion.

→ Organism: A single complete living unit. sH Osculum: Relatively large external opening of the central cavity through which water leaves a sponge.

→ Ostium: An opening to a passage or to a canal system in sponges.

→ Oviparous: Egg-laying animals, sfc Parasitic: Organism that lives during the whole life cycle upon or within another organism and from which it derives nourishment.

→ Pedal: Pertaining to the feet.

→ Pharyngeal slit: Opening in the pharynx, sis Pharynx: Anterior portion of the digestive tract between the mouth cavity and oesophagus.

→ Phylum: One of the main taxonomic divisions into which the animal kingdom is divided

→ Platyhelminthes: Phylum that includes the flatworm such as planarian.

→ Pneumatophore: Air-filled float of siphonophoran hydroids.

→ Polymorphism: Occurence of several forms in a single species.

→ Polyp: A tubular coelenterates form, sis Porocyte: Water intake cell of certain sponges, characterised by canal passing through it.

→ Post-anal tail: Muscular, posterior elongation of the body extending beyond the anus in chordates. 

→ Posterior: End of the body.

→ Predaceous: predatory.,

→ Proboscis: Tubular extension of the nose, lips or pharaynx. the extended beaklike mouth parts of insects.

→ Proglottids: Tapewarm segment.

→ Prostomium: Anterior portion of the first segment of the annelids such as earthworms overhanging the mouth region.

→ Pseudocoel: A body cavity not completely lined with mesoderm as found in round worms.

→ Radial symmetry: The condition in which similar parts are arranged about a common center like the spokes of a wheel.

→ Segmentation: Division of a body into more or less similar parts.

→ Segmented worms: Annelids.

→ Sense organ: an organ sensitive to a particular type of stimulus.

→ Setae or chaetae: Bristles such as those embedded in the body wall of the earthworm.

→ Sexual dimorphism: Phenomenon of two sexes of a given species differing in secondary characters.

→ Solitary: Living alone, not a member of the colony or group.

→ Species: A population of interbreeding individuals.

→ Spermatheca: Seminal receptacles in some female insects.

→ Spicule: One of much solid structure that composed the structural framework of a spongo.

→ Statolith: Solid body within a statocyst.

→ Swarming: Move somewhere in large numbers.

→ Tactile organs: Organ pertaining to sense of touch.

→ Tentacles: A flexible arm-like extension from the body of many invertebrates such as Hydra used in grasping and movement.

→ Testis: Sperm formation gland.

→ Tetrapod: Phylogenetic reference to an organism with a four-footed evolutionary history; includes amphibians, reptiles, birds and mammals.

→ Thorax: The middle region of the body, comprising the seven postcephalic trunk somites from the maxillipedal to the genital.

→ Triploblastic: Derived from three primary germ layers- ectoderm, mesoderm and endoderm.

→ Tube feet: Projections from the body wall, which are connected to the water vascular system and generally used for locomotion. They may also be modified to serve respiratory, food- catching and sensory functions.

→ Tubicolous: Marine worm living in a tube.

→ Tunicate: Sessile chordate that is a member of Urochordata.

→ Uniramous: An appendage with a single ramus.

→ Ureotelic: Animal whose nitrogenous excreta contain mainly urea.

→ Uricotelic: Animal whose nitrogenous excreta contain mainly uric acid.

→ Vascular system: also called the circulatory system is made up of the vessels that carry blood and lymph through the body.

→ Ventral: Pertaining to the belly, away from the back or opposite of dorsal.

→ Vertebral column: Series of separate bones joined together as a backbone.

→ Vertebrata: Members of the phylum Chordata that possess a vertebral column.

→ Water vascular system: The water vascular system maintains communication with the surrounding sea water through a group of pores in the madreporite.

→ Zygote: The product of the union of two gametes of any type.