Text book published by Government of Tamil Nadu. Tamilnadu 11th New Books Free Download PDF Online | 11th Advanced Tamil | 11th Bio- Botany|11th Bio – Zoology. Tamilnadu 11th New School Text Books Download | 11th New School Books Download Tamilnadu 11th New School Books Download.
|Language:||English, Dutch, German|
|ePub File Size:||16.46 MB|
|PDF File Size:||16.22 MB|
|Distribution:||Free* [*Register to download]|
TEXT-BOOKS OF ANIMAL BIOLOGY A General Zoology of the Invertebrates Vertebrate Zoology. Syllabus for XI Standard. ZOOLOGY - Textbooks Online. This book has been prepared by The Directorate of School from appropriate websites and reference books. Standard XII - Biology (Zoology) Syllabus. Bio Zoology 11th - Free ebook download as PDF File .pdf), Text File .txt) or read book online for free.
One of the agenda commonly placed and accepted in all these meets was the significance of biodiversity and its conservation to ensure sustainable earth. India is one of the 12 countries identified as mega centres of biological diversity. It is It comprises about 64 million hectares. Indian flora comprises about 15, flowering plants of which roughly around 1, plant species are threatened. Reptilian and amphibian fauna includes and species respectively.
Since the world has a vast range of organisms, identifying the useful, as well as harmful living beings is a need. Differentiating, grouping and giving names to living things has been an ancient activity of every human culture. Without proper classification it would be impossible to deal with enor- mous diversity of life forms.
He emphasized that animals can be classified according to their way of living, actions, habits and body parts. He observed insects, fishes, birds and whales. The insect orders like Coleoptera, Diptera were created by him.
For modern taxonomy, the first work was carried out by John Ray - of England. He divided animals into those with blood and those without blood. He also classified animals based on gills, lungs, claws, teeth and other structures. The great Swedish naturalist Linnaeus Caroli Linnaei - exerted an important influence on further advancement in taxonomy. Hence he has been called the father of taxonomy.
The taxonomists were encouraged to learn that evolution theory of Darwin gave meaning to their classifying activities. A large number of species were discovered and described. The development of modern taxonomy started during s. During this period taxonomy was based on population studies. Mayr considered species as groups of interbreeding natural populations. His book New Systematics became a landmark in the history of taxonomy.
The taxonomists were forced to accept species as a population. Hence the taxonomist started moving from the laboratory to the field. Morphological characters were studied along with other characters as behaviour, sound, ecology, genetics, zoogeography, physiology and biochemistry.
Thus taxonomy was transformed into biological taxonomy. These disciplines though appear similar have slight deviations in their meaning. The term taxonomy is a Greek word. Its components are taxis and nomos. While taxis means arrangement, nomos means law. Thus taxonomy is defined as the theory and practice of classifying organisms E.
Mayr The term systematics originates from the Greek word systema. It means placing together. Thus systematics means classification of living things in accordance with their natural relationships. G Simpson defines systematics as follows Systematics is the scientific study of the kinds and diversity of organisms and of any and all relationships among them. The term classification in meaning partly overlaps with taxonomy.
However it simply means the activity of classifying. Thus according to Simpson Zoological classification is the ordering of animals into groups on the basis of their relationships. A certain amount of overlap in meaning between the terms systamatics, taxonomy and classification is unavoidable. Based on specific charateristics, animals are grouped in various categories. These categories are otherwise called taxa singular: A taxon is a taxonomic group of any rank that is sufficiently distinct to be worthy of being assigned to a definite category.
This arrangement from Phylum to Species is designated as the hierarchic system of classification. In this system each taxon is based on specific characters of a group of organisms. Eventhough such an arrangement appears to be man made, each taxon is a natural assemblage. However, human error in identification and grouping may happen.
The taxon, Phylum is the largest group. There are several such Phyla constituting the animal kingdom. Members of a Phylum are recognised by certain distinctive features as shown below. Apart from one specific character, the members of the Phylum may also show other common characters. Since a Phylum comprises enormous varieties of animals, it is further subdivided as given below Phylum Subphylum Classes Phylum Phylum Superclass Classes.
A Class is the next level in the hierarchy. There are only few Classes in a Phylum. The members of each Class are identified by some specific character.
Thus for example the Phylum: Protozoa comprises four Classes as follows. Class Rhizopoda Ciliata Flagellata Sporozoa Character with root like pseudopodia having cilia having flagellum producing spores. An Order is another level in the taxonomic hierarchy. It is marked by some specific feature. A Class may have several Orders. For example, the Class: Insecta is subdivided into nearly 29 Orders. Each Order is identified by a specific character. Each Family will contain several Genera singular: Each Genus again is subdivided into Species.
In this hierarchy, the Species is considered as the most important taxon. A Species represents a natural unit. All other taxa remain arbitrary and are subjected to revision. A Species is considered a reality. It is the fundamental unit in taxonomy.
Evolution basically operates at the Species level only. Hence the concept of Species has received much attention. Concept of Species Initially the Species was considered as a group of organisms showing similar or specific characters. However modern workers have identified three main concepts regarding Species.
Typological Species concept - This concept has its beginning from the essentialism concept of Aristotle. According to this concept a Species is recognised by its essential characters expressed in morphology. Nominalistic Species concept - According to this concept Species are man made ideas. Nature produces individuals and not Species.
Thus a Species is considered as a mental concept. Biological Species concept - According to this concept, Species are groups of interbreeding natural populations that are reproductively isolated from other such groups. This concept is mostly accepted by present day taxonomists. Based on overall similarity, identifications are being made. The desired size of the clusters or groupings is called the operational taxonomic unit OTU. The identification method involves measurement of taxon to taxon similarity or dissimilarity.
It is measured using a scale of 0 to 1. In this method enormous amount of data are collected for related groups. Analyses are made, using statistical tools and computers. It is the first stage in the. Karyotypes within interbreeding populations of a species are usually constant. Between species there may be variation in chromosome number and size. Final stages of chromosomal aberrations such as inversions and translocations can give clues regarding intermediary stages.
Protein fractions in electrophoretic techniques, identification of amino acids in chromatography, prevalence of isoenzymes in tissue materials are all tools employed in chemotaxonomy. The occurrence of specific pheromones, colour pigments, toxins also help as keys in taxonomy. Availability of a good complete fossil provides better chance for identification.
In several fossils, their sections taken through laborious processes have provided the identification features. The fossils are normally studied along with other accompanying fossils, its geographic location and other factors.
Even though it is possible to assign a fossil to a genus or other higher level, fixing the species is not always possible. It is an integral part of taxonomy.
In fact, modern taxonomy started in with the publication of first part of Systema by Linnaeus. According to Linnaeus a Species is specified by the combination of both its specific and generic names.
Since it requires two names, it is referred to as the binomial system. This system is now firmly established in Biology. In modern times International Commissions are responsible for naming each major group of organisms. There are several such commissions. These commissions authorize the usage of scientific names in biology. The rules are set out in the codes.
The codes are modified by occasional science congresses. Basic principles of nomenclature 1. Providing stability in the naming and classification of organisms is emphasized. Any taxon must have only one correct name. If two or more names are already in use the correct name will be the one that was published earlier. This system is referred to as the law of priority.
If two or more workers at one particular time describe the same organism using different names, it results in synonyms. However only one name will be held as a valid name. The validity is provided to the senior synonym.
When names referring to two separate taxa of the same nomenclatural level are spelt the same, the two names are called homonyms. This situation arises when two separate authors used the same name to refer to two different taxa. This condition is called homonymy.
In this situation the junior name is invalid and a new replacement has to be proposed. A material on which an original description is based, gets a special status. It will form the basis for any future identity of a taxon. This idea is called the type concept.
Thus the concept of a genus and species are fixed by their type genus or type species. Names that were used prior to those included by Linnaeus in the Systema Naturae, tenth edition, are not recognised. Scientific names must be either Latin or latinized. The name should be mentioned in italics.
The genus name should be a single word beginning with a capital letter. The species name sholud be a single or compound word beginning with a smalll letter. Identification could be made thorugh literature, keys, pictures and comparison with type specimens. Of these, the most commonly used method is, using of keys.
A key is essentially a printed information or a computer software package. The construction of the key is an important job of a systematist. A good key is strictly dichotomous and not having more than two alternatives at any point. The language of a key is telegraphic. The key may be either bracketed or indented. In a bracketed key alternative contrastive characters are used for identification.
Class 11: Biology
The number on the right side indicates the next alternative character for consideration. In an indented key a series of choices are provided for identifying a taxon. The user should choose from among the choices. The following examples provide the keys for identification four species of frogs in Tamil Nadu, namely Rana hexadactyla, R.
UP Board Books PDF Free Download (यूपी बोर्ड बुक्स फ्री डाउनलोड NCERT)
The Bracketed key Genus: Rana 1 Large size, snout - vent - mm The Indented key Genus: Rana Large sized body skin smooth In all these methods the basic Taxon remains without any change. However the taxa are rearranged in different groups.
All these groupings are mostly provided for the convenience in identifying similar taxa. One of the earliest method of grouping the animals could be dividing the Animal kingdom into two assemblages called Invertebrata and Vertebrata. This scheme was provided initially by Aristotle.
This scheme does not have a place for the Prochordates. Animals can also be grouped as single celled and multicellular. The single celled organisms are called the Protozoans. The multicellular could be called the Metazoans. In this arrangement among the metazoans the unique nature of the sponges in not having a tissue grade of body constuction is not mentioned. In yet another method the animals are grouped under following three assemblages.
Protozoa - single celled animals 2. Parazoa - Multicellular without tissue grade sponges. Eumetazoa - Multicellular with tissue grade. Eumetazoa is a large group including most of the multicellular animals. Hence it is subdivided further into two groups. Diploblastic animals - having ectoderm and entoderm as two layers in the body wall. Triploblastic animals - having ectoderm, mesoderm and endoderm as three layers in the body wall. Acoelomate ectoderm mesoderm endoderm coelomic cavity Fig.
The Triploblastic animals are further divided into three groups based on the presence or absence of an embryonic body cavity called coelom. Acoelomata - no coelom Ex: Platyhelminthes 2.
Pseudocoelomata - with a false coelom Ex: Nematoda 3. Coelomata - with a true coelom IV. In a recent system, the entire living world is subdivided into 5 kingdoms. This system is much more broader including algae, fungi, and plants.
It is known as the Five kingdom concept. Monera - It includes all bacteria and the cyanobacteria. A circular DNA occurs in the cytoplasm. The cell wall is a rigid structure.
Cyanobacteria b Phylum: Protoctista or Protista - It includes single celled eukaryotes. It has two subkingdoms, namely Protozoa and Algae. Fungi 4. Plantae green plants 5.
Protozoa This phylum includes a great diversity of small, microscopic organisms. These are single celled eukaryotes. Their locomotion happens using pseudopodia, cilia or flagella. The nutrition is either autotrophic or heterotrophic. They reproduce either asexually or by sexual methods. Amoeba, Paramoecium, Plasmodium. These are multicellular, aquatic organisms.
They have a cellular grade of construction without the occurrence of tissues. The sponges belonging to this phylum are characterised by the presence of a canal system in their body. The body wall contains spicules.
They can reproduce both by asexual. All coelenterates are aquatic animals. They are mostly marine. The body is radially symmetrical. The body wall is of two layers of cells. The outer layer is called the ectoderm. The inner layer, entoderm is seperated from the ectoderm by a non-cellular mesogloea.
The mesogloea is a jelly-like substance. Due to the presence of two layers in the body wall, these are said to be diploblastic animals. Many coelenterates exhibit polymorphism. In this phylum, organisms exist in two different body forms namely, a polyp, and a medusa.
The ectoderm contains stinging cells called nematocysts cnidoblasts. These cells when triggered can explosively penetrate prey and inject poison. The layers in the body wall contain several cells and tissues such as muscle cells epithelial tissues, gland-cells and sensory cells. They reproduce both asexually and sexually. They are divided into three classes, namely Hydrozoa, Scyphozoa and Anthozoa.
In Hydrozoa, the animal has a dominant polyp body form and a reduced medusa stage. In Scyphozoa the medusa form is permanent. This group includes jelly fishes such as Aurelia. They swim in the surface waters. They have a bell shaped medusa stage. The Anthozoans mostly remain as polyps. Their body cavity is divided by large radial partitions called mesenteries. All animals of subsequent phyla show the following general characters.
All of them have three layers in the body wall. They are named as outer ectoderm, middle mesoderm, and inner endoderm. Thus they are called as Triploblastic animals.
The body is bilaterally symmetrical. This phylum includes flatworms. These are acoelomates, without a body cavity called coelom. The alimentary canal is either absent or very simple. Excretion and osmoregulation occur through flame cells. These worms are mostly hermophrodites, having both male and female reproductive organs in a single individual.
Most of the members are parasites. It is divided into three classes, namely Turbellaria, Trematoda and Cestoda.
Class Turbellaria: The Planaria of this class shows characteristic regeneration. Class Trematoda: A protective cuticle covers the outer surface of the body. Flukes have suckers for attachment to the host tissues. The examples are Fasciola liver fluke , Schistosoma blood fluke.
Class Cestoda: These are internal parasites with a complex life history. The life cycle involves two hosts. Their body characters are adaptations for parasitic life. Mouth and alimentary canal are absent. Food is absorbed through general body surface.
The head is called the scolex. It has a ring of hooks and suckers for attachment to the host tissue. The body consists of several segments called Proglottids. These are the popular round worms. The body is narrow and pointed at both the ends. There are no body segments. The body is covered by a thin cuticle. The body cavity is considered as a pseudocoelom. The alimentary canal is a straight tube. They reproduce sexually and the sexes are seperate. There are several free living soil nematodes.
Others are parasites. In subsequent Phyla the animals show following general characters 1. There is a coelom within the mesoderm. Hence these are called as coelomates. The body consists of a series of compartments. This phenomenon is called as metameric segmentation.
They have a circulatory system providing internal transport. These are worm like animals. The body segments are rings externally. Internally the segments are seperated by septa. Externally the body is protected by a cuticle.
Excretion and osmoregulation are acheived by ciliated tubules called nephridia. There is a central nervous system. The brain is. The nerve cord is ventral in position.
Tamilnadu Syllabus New 11th Books Free Download PDF
For the first time head formation or cephalization happens. These are bisexual and hermophroditic. The larva is called the trochophore. This phylum includes three Classes, namely Polychaeta, Oligochaeta and Hirudinia. The polychaetes are marine worms. They have a distinct head. There are pairs of lateral projections called parapodia. The examples are Nereis ragworms , Arenicola lugworm.
Earthworms are included in the Class Oligochaeta. The Class: Hirudinia includes leeches. These are blood suckers and ectoparasites. They have well developed suckers for attachement at anterior and posterior ends. These are the most successful group of animals. They outnumber all other animals in population strength. The body is segmented. It is covered by a hard exoskeleton made of chitin.
During growth the exoskeleton is shed moulting of ecdysis. The legs or paired appendages are jointed. The head.
Each compound eye is made up of several photoreceptor sub units called Ommatidia. They have an open circulatory system without vessels. The body cavity is filled with a fluid called haemolymph. Such body cavity is known as haemocoel. These are unisexual, exhibiting sexual dimorphism. The young forms produced are invariably called the larvae. The larvae undergo metamorphosis and develop into adults.
This Phylum comprises five Classes, Class Onychophora: It includes small worm like Peripatus. Peripatus shows Annelidan and Arthropoda characters. Hence this may be considered as a connecting link between the two groups. Class Crustacea: The dorsal body surface is covered by a sheild like carapace.
Class Myriapoda: These organisms have a distinct head and simple eyes. The centepedes have a pair of poison claws. The body consists of numerous segments, bearing pairs of legs. Class Insecta: The body is divided into head thorax and abdomen. In several insects, the adults have two pairs of wings on the thorax. Respiration happens through the tracheal system. Class Arachnida: The body is divided into cephalothorax and abdomen.
There are four pairs of legs attached to the cephalothorax. Phylum Mollusca: Considered to be the second largest group of animals with regard to species number. These are soft bodied animals without segmentation. The body is divided into head, muscular foot and visceral mass. The body is covered by a mantle and a shell. Respiration happens through gills ctinidia in the mantle cavity. The most common larva is a trochophore larva. There are seven classes of which three are more prominent.
Class Pelecypoda or Bivalvia: They burrow in mud and sand. The body is laterally compressed. Class Gastropoda: They posses a spiral shell. The foot is large and flat.
They have well developed head with tentacles and eyes. Class Cephalopoda: They are adapted for swimming. The foot is modified into eight to ten long tentacles in the head region. The shell is either internal or absent. Phylum Echinodermata: While the adults are radially symmetrical the larvae remain bilaterally symmetrical.
The mouth is on the lower surface. They have a water vascular system with tube feet. Phylum Chordata This phylum derives its name from one of the common characteristics of this group namely the notochord Gr.
The animals belonging to all other phyla of the Animal Kingdom are often termed the non -chordates or the invertebrates since they have neither notochord nor backbone in their body. The backboned animals vertebrates , together with a few closely related animals which do not possess a backbone, are included in this phylum. Most of the living chordates are familiar vertebrate animals. The chordates are of primary interest because human beings are members of this group.
Diversity of Chordates The chordates exhibit an astonishing diversity in form, physiology and habits. The number of chordate species is limited. About 49, species are on record which are only half of the living species of molluscs and less than one tenth of arthropods.
Despite their modest number of species, the chordates make remarkable contribution to the bio-mass of the earth. Nearly all of them are medium to large in size. The vertebrates in particular are considerably larger and many of them are among the largest of living animals. The gigantic blue whale which is 35 meters long and tons in weight is the biggest known animal.
The smallest vertebrate , philippine goby is a fish, measuring only 10 mm in length. The chordates are able to occupy various kinds of habitats. They have adapted themselves to more modes of existence than any other group.
They are found in the sea, in freshwater, in the air and on all parts of land from the poles to the equator. General Characters: The three distinctive characteristics of the chordates are the presence of notochord, dorsal tubular nerve cord and pharyngeal gill slits. The board also decided to introduce only one paper. This will reduce the number of final board examination days.
Books have been colleagues of youth for a long time. They have served humankind from times obscure. Books have opened a vista to the wide entryway of learning, instruction, investigation and information. We not just gain from a book, book additionally improves our capacity of creative energy.
NCERT books are the books that score an unmistakable full stamp with regards to satisfying the previously mentioned criteria. They are unmistakably the best educative books you can lay your hands on. It resembles as though you are educated by an individual coach.
The writings are informed with ends; this encourages the understudy to look upon the primary features without experiencing the whole content. These books are all around educated and impartial.The body cavity is filled with a fluid called haemolymph. Thus taxonomy was transformed into biological taxonomy.
In the hindlimbs there are four toes with the first directed backwards. The pollex or thumb or first toe are smaller than other digits and are opposable except the hallux of man.
They differ in size, colouration and feather arrangement. Previous Years Entrance Examination Questions with answers are provided.
- ANNA AND THE FRENCH KISS PDF ENGLISH
- ANALOG AND DIGITAL COMMUNICATION EBOOK
- SHE COMES FIRST DEUTSCH PDF
- THICK FACE BLACK HEART EBOOK
- EBOOK UML GRATIS
- ASIA CUP T20 SCHEDULE PDF
- MALLEUS MONSTRORUM PDF
- LANGUAGE TO GO UPPER INTERMEDIATE TEACHERS BOOK
- VEDIC MATHS TRICKS BOOK PDF
- PDF FILE PRINTER DRIVER
- EBOOK MERANTAU KE DELI
- THE WAIT BOOK PDF