Unit–I Diversity of Living Organisms 27 Periods
Chapter–1 : The Living World
What is living ? Biodiversity; Need for classification; three domains of life : taxonomy and systematics; concept of species and taxonomical hierarchy; binomial nomenclature; tools for study of taxonomy-museum, zoological parks, herbaria, botanical gardens.
Chapter–2 : Biological Classification
Two kingdom classification, Five kingdom classification; Salient features and classification of Monera, Protista and Fungi into major groups; Lichens,Viruses and Viroids.
Chapter–3 : Plant Kingdom
Salient features and classification of plants into major groups – Algae, Bryophyta, Pteriodophyta, Gymnospermae and Angiospermae (three to five salient and distinguishing features and at least two examples of each category); Angiosperms –classification upto class, characteristic features and examples.
Chapter–4 : Animal Kingdom
Salient features and classification of animals non-chordates up to phyla level and chordates up to class level (three to five salient features and at least two examples of each category).
**(No live animals or specimen should be displayed.)
Unit–II Structural Organisation in Animals and Plants 27 Periods
Chapter–5 : Morphology of Flowering Plants
Morphology and modifications : Internal morphology of different plants : root, stem, leaf, Inflorescence, flower, fruit and seed. (to be dealt with relevant experiments of the Practical Syllabus).
Chapter–6 : Anatomy of Flowering Plants
Anatomy and functions of different tissues.
Chapter–7 : Structural Organisation in Animals
Animal tissues (epithelial, connective, muscular and nervous tissue), Brief account of morphology, anatomy and functions of different systems (digestive, circulatory, respiratory, nervous and reproductive) of an insect (cockroach).
Unit–III Cell : Structure and Function 26 Periods
Chapter–8 : Cell-The Unit of Life
Cell theory and cell as the basic unit of life : Structure of prokaryotic and eukaryotic cells; Plant cell and animal cell; cell envelope; cell membrane, cell wall; cell organelles–structure and function; endomembrane system, endoplasmic reticulum, Golgi bodies, lysosomes, vacoules ; mitochondria, ribosomes, plastids, microbodies; cytoskeleton, cilia, flagella, centrioles (ultrastructure and function);
nucleus.
Chapter–9 : Biomolecules
Chemical constituents of living cells : Biomolecules, structure and function of proteins, carbohydrates, lipids, nucleic acids, enzymes– types, properties, enzymes action.
Chapter–10 : Cell cycle, mitosis, meiosis and their significance.
Unit–IV Plant Physiology 40 Periods
Chapter–11 : Transport in Plants
Movement of water, gases and nutrients; cell to cell transport, Diffusion, facilitated diffusion, active transport; plant-water relations, imbibition, water potential, osmosis, plasmolysis; long distance transport of water–absorption, apoplast, symplast, transpiration pull, root pressure and guttation; opening and
closing of stomata and transpiration; Uptake and translocation of mineral nutrients– transport of food, phloem transport, mass-flow hypothesis.
Chapter–12 : Mineral Nutrition
Essential minerals, macro-and micronutrients and their role; deficiency symptoms; mineral toxicity; elementary idea of hydroponics as a method to study mineral nutrition; nitrogen metabolism, nitrogen cycle, biological nitrogen fixation.
Chapter–13 : Photosynthesis in Higher Plants
Photosynthesis as a mean of autotrophic nutrition; site of photosynthesis, pigments involved in photosynthesis (elementary idea); photochemical and biosynthetic phases of photosynthesis, cyclic and non-cyclic photophosphorylation; chemiosmotic hypothesis; photorespiration; C3 and C4 pathways; factors affecting photosynthesis.
Chapter–14 : Respiration in Plants
Exchange of gases; cellular respiration–glycolysis, fermentation (anaerobic), TCA cycle and electron transport system (aerobic); energy relations–number of ATP molecules generated; amphibolic pathways; respiratory quotient.
Chapter–15 : Plant–Growth and Development
Seed germination; phases of plant growth and plant growth rate; conditions of growth; differentiation, dedifferentiation and redifferentiation;’ sequence of developmental processes in a plant cell; growth regulators–auxin, gibberellin, cytokinin, ethylene, ABA; seed dormancy; vernalisation; photoperiodism.
Unit–V Human Physiology 40 Periods
Chapter–16 : Digestion and Absorption
Alimentary canal and digestive glands, role of digestive enzymes and gastrointestinal hormones; Peristalsis, digestion, absorption and assimilation of proteins, carbohydrates and fats; calorific values of proteins, carbohydrates and fats; egestion; nutritional and digestive disorders–PEM, indigestion, constipation, vomiting, jaundice, diarrhoea.
Chapter–17 : Breathing and Exchange of Gases
Respiratory organs in animals (recall only); Respiratory system in human; mechanism of breathing and its regulation in humans–exchange of gases, transport of gases and regulation of respiration, respiratory volume; disorders related to respiration–asthma, emphysema, occupational respiratory disorders.
Chapter–18 : Body Fluids and Circulation
Composition of blood, blood groups, coagulation of blood; composition of lymph and its function; human circulatory system–structure of human heart and blood vessels; cardiac cycle, cardiac output, ECG; double circulation; regulation of cardiac activity; disorders of circulatory system–hypertension, coronary artery
disease, angina pectoris, heart failure.
Chapter–19 : Excretory Products and Their Elimination
Modes of excretion–ammonotelism, ureotelism, uricotelism; human excretory system–structure and function; urine formation, osmoregulation of kidney function–renin–angiotensin, atrial natriuretic factor (ANF), ADH and diabetes insipidus; role of other organs in excretion;’ disorders– uraemia, renal
failure, calculi, nephritis; dialysis, artificial kidney and kidney transplant.
Chapter–20 : Locomotion and Movement
Types of movement–Ciliary, flagellar, muscular; skeletal muscle–contractile proteins and muscle contraction; skeletal system and its functions; joints; disorders of muscular and skeletal system–myasthenia gravis, tetany, muscular dystrophy, arthritis, osteoporosis, gout.
Chapter–21 : Neural Control and Coordination
Neuron and nerves; Nervous system in humans–central nervous system; peripheral nervous system and visceral nervous system; generation and conduction of nerve impulse; reflex action; sensory perception sense organs; elementary structure and functions of eye, ear, nose and tongue.
Chapter–22 : Chemical Coordination and Integration
Endocrine glands and hormones; human endocrine system–hypothalamus, pituitary, pineal, thyroid, parathyroid, adrenal, pancreas, gonads; mechanism of hormone action (elementary idea); role of hormones as messengers and regulators, hypo–and hyperactivity and related disorders; dwarfism, acromegaly, cretinism, goiter, exophthalmic goitre, diabetes, Addison’s disease.
A. List of Experiments 60 Periods
1. Study and description of three locally available common flowering plants, one from each of the families Solanaceae, Fabaceae and Liliaceae including dissection and display of floral whorls, anther and ovary to show number of chambers (floral formulae and floral diagrams). Types of root
(Tap and adventitious); stem (herbaceous and woody); leaf (arrangement, shape,venation, simple and compound).
2. Preparation and study of T.S. of dicot and monocot roots and stems (primary).
3. Study of osmosis by potato osmometer.
4. Study of plasmolysis in epidermal peels (e.g. Rhoeo leaves).
5. Study of distribution of stomata in the upper and lower surface of leaves.
6. Comparative study of the rates of transpiration in the upper and lower surface of leaves.
7. Test for the presence of sugar, starch, proteins and fats. Detection in suitable plant and animal materials.
8. Separation of plant pigments through paper chromatography.
9. Study of the rate of respiratioin in flower buds/leaf tissue and germinating seeds.
10. Test for presence of urea in urine.
11. Test for presence of sugar in urine.
12. Test for presence of albumin in urine.
13. Test for presence of bile salts in urine.
B. Study/observation of the following (spotting)
1. Study of the parts of a compound microscope.
2. Study of the specimens/slides/models and identification with reasons– Bacteria, Oscillatoria, Spirogyra, Rhizopus, mushroom, yeast, liverwort, moss, fern, pine, one monocotyledonous plant, one dicotyledonous plant and one lichen.
3. Study of virtual specimens/slides/models and identification with reasons– Amoeba, Hydra, liver-fluke, Ascaris, leech, earthworm, prawn, slik-worm, honeybee, snail, starfish, shark, rohu, frog, lizard, pigeon and rabbit.
4. Study of tissues and diversity in shapes and sizes of plant and animal cells (palisade cells, guard cells, parenchyma, collenchyma, sclerenchyma, xylem, phloem, squamous epithelium, muscle fibers and mammalian blood smear) through temporary/permanent slides.
5. Study of mitosis in onion root tip cells and animals cells (grasshopper) from permanent slides.
6. Study of different modifications in roots, stems and leaves.
7. Study and identification of different types of inflorescence (cymose and racemose).
8. Study of imbibition in seeds/raisins.
9. Observation and a comments on the experimental set up for showing :
(a) Anaerobic respiration
(b) Phototropism
(c) Effect of apical bud removal
(d) Suction due to transpiration
CHAPTER 1 - THE LIVING WORLD
Points to Remember
1. Organism (Microorganism, plant and animals) who posseses life is living.
2. Life is a complex organisation expressing itself through chemical reactions and exhibit characteristics of living organisms.
3. Characteristics of Living Organisms : Growth, reproduction, metabolism, cellular organisation, consciousness, self-replicating and self regulation.
Reproduction and growth are NOT defining properties.
Metabolism (Catabolic + Anabolic), cellular organisation and consciousness are defining properties.
Living organisms are self-replicating, evolving, self-regulating and interactive systems capable of responding to external stimuli.
4. Biodiversity : The term used to refer to the variety of microorganisms, plant and animals on earth.
5. Need for classification : To organise the vast number of microorganisms, plants and animals into categories that could be named, remembered, studied and understood.
6. Three Domains of Life : Proposed by Carl Woese in 1990, who also proposed the six kingdom classification for living organisms. The three Domains of life are Archaea, Bacteria and Eukarya.
7. Taxonomy : Study of principles and procedures of identification, nomenclature and classification.
8. Systematics : It deals with classification of organisms based on their diversities and relationships among them. The term was proposed by Carolus Linnaeus who wrote ‘Systema Naturae’.
9. Concept of Species : All the members that can interbreed among themselves and can produce fertile offsprings are the members of same species. This is the biological concept of species proposed by Mayr.
10. Taxa : Each category (i.e., unit) of classification is called as a taxon.
11. Taxonomic Hierarchy : Classification of organisms in a definite sequence of taxon or category or rank in a descending order.
Kingdom → Phylum /Division → Class → Order → Family → Genus → Species.
12. Binomial Nomenclature : Given by Carolus Linnaeus. Each scientific name has two components-Generic name + Specific epithet.
13. ICBN : International Code for Botanical Nomenclature (for giving scientific name to plants.)
14. ICZN : International Code of Zoological Nomenclature (for giving scientific name to animals.)
15. Rule for Nomenclature :
Latinised names are used.
First word is genus, second word is species name.
Printed in italics; if handwritten then underlined separately.
First word starts with capital letter while species name written in small letter.
16. Scientific names of some organisms :
Man — Homo sapiens
Housefly — Musca domestica
Mango — Mangifera indica
Wheat — Triticum aestivum
17. Taxonomical Aids are the tools for study of taxonomy.
18. Museums in educational institutes (school and colleges) have collection of skeletons of animals, stuffed and preserved specimens of organisms for study and reference.
19. Zoological Parks (Places where wild animals are kept in protected environment under human care) Example : National Zoological Park, Delhi.
20. Herbarium : Store house of dried, pressed and preserved plant specimen on sheets, kept systematically according to a widely accepted system of classification, for future use
Anatomy of Flowering Plants NEET Previous Year Solved Questions
Morphology of Flowering Plant NEET Previous Year Solved Questions
Animal Kingdom NEET Previous Year Solved Questions
Plant Kingdom NEET Previous Year Solved Questions
Biological Classification NEET Previous Year Solved Questions
The Living World NEET Previous Year Solved Questions
Morphology of Flowering Plants NEET MCQ Questions
Anatomy of Flowering Plants NEET MCQ Questions
Structural Organisation in Animals NEET MCQ Questions
Respiration in Plants NEET UG MCQ Questions
Chemical Coordination and Integration NEET MCQ Questions
Neural Control and Coordination NEET MCQ Questions
Locomotion and Movement NEET UG MCQ Questions
Excretory Products and Their Elimination NEET MCQ Questions
Body Fluids and Circulation NEET UG MCQ Questions
Breathing and Exchange of Gases NEET MCQ Questions
Digestion and Absorption NEET UG MCQ Questions
Plant Growth and Development NEET MCQ Questions
Photosynthesis in Higher Plants NEET MCQ Questions
Very Short Answer Question (1 mark each)
1. Define species.
2. What is systematics ?
3. Give the names of two famous botanical gardens.
4. Define Life
5. Name two genus belonging to family Felidae?
6. Assertion: In planaria larva, a fragmented organism regenerates the lost body
part of its body and becomes, a new organism.
Reason: Reproduction is defining feature of life forms.
(a) Both assertion and reason are true, and the reason is the correct
explanation of the assertion.
(b) Both assertion and reason are true, but the reason is not the correct
explanation of the assertion.
(c) Assertion is true but reason is false.
(d) Both assertion and reason are false
CHAPTER 2 - BIOLOGICAL CLASSIFICATIONS
Points to Remember
Systems of Classification :
Earliest classification was given by Aristotle. Divided plants into herbs,
shrubs and trees.
Animals into those with red blood and those who do not have it.
Two kingdom classification : Given by Carolus Linneaeus–Kingdom– plantae and kingdom–Animalia.
Five kingdom classification : By R.H. Whittaker, Monera, Protista, Fungi, Plantae and Animalia are the five kingdoms.
The main criteria for classification of organisms into five kingdoms include cell structure, thallus organisation, mode of nutrition, reproduction and phylogenetic relationships.
Kingdom Monera :
Has bacteria as sole members.
Cell wall made up of peptidoglycan.
Bacteria can have shapes like : Coccus (spherical), Bacillus (rod-shaped), Vibrium (comma shaped) and spirillum (spiral shaped).
Bacteria found almost everywhere and can be Photosynthetic autotrophs,Archaebacteria
Halophiles (salt-loving)
Thermoacidophiles (in hot springs)
Methanogens (in marsh and in gut of ruminant animals. Produce methane gas.)
Eubacteria
Photosynthetic autotrophs like Cyanobacteria (Blue-green algae BGA). Some like Anabaena and Nostoc have specialized cells called heterocysts for nitrogen fixation.
Algae bloom is rich growth of blue green algae over the surface of polluted water bodies.
Algae bloom releases neurotoxins, deplete oxygen and makes water unfit for use.
Chemosynthetic autotrophs : Oxidise various inorganic substances like nitrates/nitrites, ammonia and use released energy for their ATP production.
They helps in nutrients recycling of N, P, Fe and S.
Heterotrophic bacteria : Decomposers help in making curd, production of antibiotic, N2 fixation, casuse diseases like cholera, typhoid, tetanus and citrus canker. Mycoplasmas : Completely lack cell wall. Smallest living cells. Can survive without oxygen. Pathogenic in animals and plants.
1. Artificial System of Classification
1. It utilise one or two morphological trail.
2. Homology is never standard.
3. The system does not employ characters from anatomy cytology, biochemistry, genetics etc. for grouping of organisms.
2. Natural System of Classification
1. The system employs several morphological character for grouping of orgaism.
2. It studies homology in all characters including morphology, anatomy etc.
3. This system gives information about both Natural relationship and phylogenyChemosynthetic autotrophs or Heterotrophs.
Very Short Answer Question (1 mark each)
1. Nostoc and Anabaena have specialized cells called heterocysts. What is the
function of these cells ?
2. Which group comprises of single celled eukaryotes only ?
3. Which organisms are the chief producers in oceans ?
4. Name the fungus which causes disease in wheat (i) rust (ii) smut.
5. Which Ascomycetes has been used extensively in biochemical and genetic
work ?
6. What is the principle underlying the use of cyanobacteria in agriculture ?
7. Define dikaryon stage. Where do you observe this stage?
8. Differentiate between zoospore and zygospore?
Short Answer Question-I (2 marks each)
9. How are bacteria classified on the basis of their shapes ?
10. What is the mode of reproduction in bacteria ?
11. Why are red tides caused and why are they harmful ?
12. Viruses and viroids differ in structure and the diseases they cause. How ?
13. Which class of kingdom fungi has both unicellular as well as multicellular
member ? When is a fungus called coprophilous ?
14. Why two kingdom classification was not sufficient? Explain with the help
of two examples.
15. What is the difference between Archaebacteria and Eubacteria?
16. How flexibility is maintained in the body of Euglena?
CHAPTER - 3 PLANT KINGDOM
Points to Remember
Classification :
Artificial System of Classification
By Carolus Linnaeus, based on androecium structure and vegetative characters.
Natural System of Classification
Based on natural affinities among organisms
Included external as well as internal features
By Geroge Bentham and J.D. Hooker
Phylogenetic System of Classification
Based on evolutionary relationships between the various organisms
By Engler and Prantl
Later on By Hutchinson
Numerical Taxonomy :
Carried out using computers
Based on all observable characteristics
Data processed after assigning number and codes to all the characters.
Advantages : Each character gets equal importance and a number of
characters can be considered.
Cytotaxonomy :
Based on cytological informations.
Gives importance to chromosome number, structure and behaviour. Chemotaxonomy :
Based on Chemical constituents of the plants. Algae :
Chlorophyll bearing, simple, thalloid, autotrophic and largely aquatic
organisms.
Importance of Algae :
Help in carbon dioxide fixation by carrying out photosynthesis and have
immense economic importance.
At least half of the total carbon dioxide fixation on earth carried out by them.
Increases dissolved oxygen level in their environment.
Many species like Laminaria, Sargassum, Porphyra etc. are used as food.
Agar obtained from Gelidium and Gracilaria which is used in ice-creams
and jellies and to grow microbes.
Algin obtained from brown algae and carrageen from red algae used
commercially as hydrocolloids.
Chlorella and Spirullina are unicellular algae, rich in protein and used even
by space travellers.
Algae are unicellular like Chlamydomonas, colonial like Volvox or or
filamentous like spirogyra and Ulothrix. Occur in water, soil, wood moist
stones etc.
Algae are divided into 3 classes.
(i) Chlorophyceae
Green algae, Main pigment is chlorophyll ‘a’ and ‘b’.
Cell wall has inner layer of cellulose and outer layer of pectose.
Has pyrenoids made up of starch and proteins.
Pigment and pyrenoids are located in Chloroplast.
Reproduction in Bryophytes
Vegetative reproduction by fragmentation.
Asexual reproduction by gemmae formed in gemma cups.
Sexual reproduction : Main plant body is haploid, produces gametes and so
called Gametophyte. By fusion of antherozoids produced in antheridium
and egg cell produced in archegonium, results in formation of zygote which
develops into sporophytic structure differentiated into foot, seta and capsule.
Spores produced in a capsule germinate to from free-living gametophyte
(Protonema). Sporophyte is not free living but attached to photosynthetic
gametophyte from which it derives nutrition.
Pteridophytes :
First terrestrial plants.
Prefer cool, damp and shady places to grow.
Grown as ornamentals.
Used for medicinal purpose, as soil binder.
Main plant body is sporophyte which is differentiated into true root, stem
and leaves.
Leaves may be small as in Selaginella or large as in ferms.
Sporangia having spores are subtended by leaf-like appendages called
sporophylls. (Sporphylls may be arranged to form strobili or cones.)
In Sporangia, the spore mother cells give to spores after meiosis.
Spores germinate to form haploid gametophytic structure called prothallus
which is free living, small, unicellular and photosynthetic.
Prothallus bears antheridia and archegonia which bear antherozoids and
egg cell respectively which on fertilisation from zygote. Zygote produces
multicellular, well differentiated sporophyte
Gymnosperms :
Have naked seeds as the ovules are not enclosed by any ovary wall and
remain exposed.
Includes shrubs and trees (medium and tall sized).
Have generally tap roots, stem may be unbranched (Cycas) or branched
(Pinus, Cedrus), leaves–needle like (Pinus) and pinnate (Cycas).
Roots of Pinus have fungal association in the form of mycorrhiza.
Cycas have small specialized roots called coralloid root which are associated
with N2 fixing cyanobacteria.
Heterosporous–Produce haploid microspores and megaspores.
Male cone has microsporophylls which bear microsporangia having
microspores which develop into reduced gametophyte called pollengrain.
Female cone has megasporophylls which bear megasporongia having
megaspores which are enclosed within the megasporangium (Nucellus).
One megaspore develops into female gametophyte bearing two or more
archegonia.
Pollen grains carried in air currents reach ovules, form pollen tube which
reach archegonia and release male gametes which fertilise egg cell and form
zygote which produce embryos. Ovules develop into seeds which are not
covered.
Short Answer Question-I (2 marks each)
8. Sphagnum has a lot of economic importance. Justify.
9. Gymnosperms can show polyembryony. Why do you think so ?
10. How is leafy stage formed in mosses ? How is it different from
protonema ?
Short Answer Question-II (3 marks each)
11. The leaves in gymnosperms are adapted to withstand xerophytic conditions.
Justify.
12. The gametophytes of bryophytes and pteridophytes are different from that
of gymnosperms. How ?
13. Roots in some gymnosperms have fungal or algal association. Give examples,
their names and role in the plants.
14. Why is presence of water a must for fertilisation in pteridophytes ?
15. Draw a neatly labelled diagram of Funaria?
16. Differentiate between three classes of algae.
17. Mention any three economic importance of algae.
18. Differentiate between isogamous, anisogamous and oogamous reproduction
in algae.
19. Explain the life cycle of bryophytes.
Long Answer Questions (5 marks each)
20. Draw the life cycle of an angiosperm alongwith a brief note on double
fertilisation.
21. Explain alternation of generation in plants.
22. Explain various classes of Algae
CHAPTER 4 - ANIMAL KINGDOM
Basis of Classification :
Animals are classified on the basis of following few fundamental features—
1. Levels of Organisation :
(1) Cellular level : Cells are arranged as loose cell aggregates, e.g.,sponges.
(2) Tissue level : The cells performing the same function are arranged into
tissues, e.g., Coelenterates.
(3) Organ level : Tissues are grouped together to form organs, each specialised for a particular function. e.g., platyhelminthes.
(4) Organ system level : organs are associated to form functional systems e.g., Annelids, Arthropods, Molluscs, Echinoderms and Chordates.
Example : Circulatory System.
Open type : Blood pumped out through heart. Not confined to blood vessels. Cells and tissues are directly bathed in it.
Closed types : Blood is circulated through blood vessels (arteries,veins and
capillaries)
2. Symmetry :
Asymmetrical : Cannot be divided into equal halves through median plane e.g., Sponges.
Radial symmetry : Any plane passing through central axis can divide organism
into identical halves. e.g., coelentrates,Ctenophores and echinoderms.
Bilateral symmetry : Only one plane can divide the organism into two identical
eft and right halves e.g., Annelids and Arthropods.
3. Germinal Layers :
Diploblastic : Cells arranged in two embryonic layers i.e., external ectoderm and internal endoderm. (Mesoglea may be present in between ectoderm and
endoderm) e.g., porifers and Coelentrates. (Cnidarians)
Triploblastic : Three layers present in developing embryo i.e., ectoderm,
mesoderm and endoderm. e.g., Platyhelminthes to Chordates. Coelom (Body cavity which is lined by mesoderm)
Coelomates : Have coelom e.g., Annelids, Arthropods, molluscs, Echinoderms,
Chordates etc.
Pseudocoelomates : No true coelem as mesoderm is present in scattered
pouches between ectoderm and endoderm. e.,g., Aschelminthes.
Acoelomates : Body cavity is absent e.g., Platyhelminthes.
5. Segmentation (A) True Metamerism : Found Annelida,Arthropoda,
Chordata :
Segmentation is external as well as a internal in Annelids.
Segmentation is external in Arthropods.
Segmentation is internal in chordates.
Metamerism : If body is externally and internally divided into segments
(metameres) with serial repetition of atleast some organs, then phenomenon is
called metamerism e.g., Earthworm. (B) Pseudometamerism : Found in
tapeworm. The proglottids (segments of tapeworm) budded off from neck
not embryonic in origin.
6. Notochord :
Rod-like structure formed during embryonic development on the dorsal side.
It is mesodermally derived e.g., Chordates.
Non-chordates do not have notochord .e.g., porifera to echinoderms.
Phylum Porifera :
Also called sponges.
Are usually marine and asymmetrical.
Have cellular level of organisation and diploblastic animals.
Food gathering, respiratory exchange and removal of wastes occurs through
water canal system. Digestion intracellular.
Ostia (minute pores on body), spongocoel (body cavity) and osculum help
in water transport. They are lined by choanocytes (collar cells).
Body wall has skeleton of spicules or spongin fibres.
Animals are hermaphrodite. Fertilisation internal. Development is indirect
(i.e., has a larval stage distinct from adult stage) e.g., Sycon, Euspongia.
Spongilla (Fresh water sponge)
Phylum Coelenterata :
Also called Cnidarians.
Are usually marine and radially symmetrical.
Sessile or free swimming
Phylum Ctenophora :
Also called as sea walnuts or comb jellies.
Are exclusively marine, radially symmetrical.
Have tissue level organisation, are diploblastic.
Digestion both extra and intracellular.
Body has eight external rows of ciliated comb plates for locomotion.
Show Bioluminescence (Property of living organisms to emit light).
Hermaphrodite (sexes are not separate).
Only sexual reproduction occurs. Exernal fertilization. Indirect development.
e.g., Ctenoplana, Pleurobrachia.
Phylum Plathyhelminthes :
Also called as ‘flat worms’.
Have dorsoventrally flattened body. Are mostly endoparasites in animals.
Are bilaterally symmetrical, triploblastic, acoelomate,with organ level of
orgnisation.
Absorb nutrients through body surface.
Parasitic forms have hooks and suckers.
‘Flame cells’ help in osmoregulation and excretion
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