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Details of Adenohypophysis

In this page- Adenohypophysis  i. Pars distalis ii. Pars tuberalis iii. Pars intermedia     Adenohypophysis- Adenohypophysis is developed from the oral ectoderm. It is divisible into 3 parts i. Pars distalis ii. Pars tuberalis iii. Pars intermedia Pars distalis, pars tuberalis, pars intermedia consists of the anterior lobe of pituitary gland. 1. Pars distalis The part of adenohypophysis is made up of parenchymal cell. It is of two types A. Chromophobes The important character of these cells are they apper in groups near the centre of cord. In ordinary preparation, the cell membrane are not distinguishable. Secretory granules are mostly absent. They do not secrete any hormone. They give rise to other types of cells. B. Chromophylls In chromophylls again two cells are found. They are a. Acidophills These are readily stained with acid dyes. It is of two types. i. Somatotroph or somatotrophic cells The round and ovoid in shaped cells are the secrerory cells. They are pre...

How do we feel when we touch a human salivary glands?

  How do we feel when we touch a human salivary glands? Human saliva is secreted by three major types salivary glands  which are 1.  Parotid glands 2.  Submandibular or submaxilary glands 3.  Sublingual glands Which are present in different parts of mouth along with these there are also some minor salivary glands present on our checks and lips also. When we touch a human salivary glands we feel wet as the secretion of this gland which is saliva contains 99.05% water and 0.05% solute.  Want to know why it feels watery when we touch a human salivary glands in details? then read below to get your answer clearly.  Salivary glands  Salivary gland  is an exocrine gland. It releases a  secretion of saliva  in oral cavity. It is important to clean mouth and keep moist the mouth and pharynx. when the food s entered into the mouth the tactile receptors sense it and promote  salivary glands . Even when we think about the food the  sa...

Structure and function of neurohypophysis

In this page- Neurohypophysis   Hormones of neurohypophysis     i. Vasopresin and its functions    ii. Oxytocin and its functions   Neurohypophysis Neurohypophysis develops from neural ectoderm. It is called posterior lobe. The cells of neurohypophysis are called pituicytes. These are fusiform cells. Yellow and brown pigments are present in these cells. They are called pituicytes of Bucy. Granules of pituicytes are composed to unsaturated neutral fat and such, they are easily stained with asmic acid. The hormone pass down along axon in the hypothalamus hypophysial tract into the posterior lobe of the hypophysis. The hormones are stored in the neurohypophysis . Hormones of neurohypophysis The hormones of the neurohypophysis are actually secreted by the nuclear of the hypothalamus. Neurohypophysis is the storage area for the release of these hormones. These are two very important hormones of the neurohypophysis . i. Vasopresin or anti-diuretic hor...

Morphology and anatomy of pituitary gland

In this page - Pituitary gland    1. Adenohypophysis        i. Pars distalis        ii. Pars tuberalis       iii. Pars intermedia    2. Neurohypophysis   Pituitary gland  The pituitary gland is very complicated endocrine gland with many crucial functions. It is otherwise called hypophysis. It controls all the endocrine glands, so it is called master gland. In 16th century vesalius named the pituitary gland. The gland is the best protected oxygen of body. The pituitary body is attached to the hypothalamus by means of a stalk. Shape- It is small, oval shaped structure, situated at the base of brain, in the sella turcica at the sphenoid bone. Size- The pituitary gland in man measures 1.2 to 1.5 cm and average weight is 0.5 gm. Color- The pituitary gland is reddish-grey in colour. Blood supply- The blood vessels for the hypothalamus arise from superior hypophysial branches of the interior carotid arter...

Five kingdom classification of living beings

Need for classification   For keeping books completely different subjects a different almirah are employed in an honest library in order that after we would like a specific book of geographies, English, History, Physics, Chemistry, biology or the zoological science etc.  We will at once do away with that book from that section or an almirah.  If these books don't seem to be unbroken in such systematic means we have a tendency to cannot do away with needed a book out of the assemblage of thousands of books.  A simmilarly inspire of a good diversity amongst the animals, the kingdom is well organized and is incredibly systematic. For the systematic study animals are divided into minor and major teams on the premise of similarities and variations.  Every cluster has been given a specific name relying upon their characteristics.  As an example completely different sorts of birds are enclosed in a class supported their structural and physiological similariti...

Study of morphology of angiospermic plant

Study of morphology of angiospermic plants, root,stem,leaf,flower,fruit Morphology of angiospermic plants The study of assorted external options of the plants is understood as plant morphology.  The angiosperms  is characterized by presence of roots, stems, leaves, flowers, and fruits.  These are the most important characteristics of angiosperms.  Root The root is underground a part of the plant and developed from elongation of raddicle.  There are four main functions of the foundation system  1. The absorption of water and minerals from the soil.  2. Providing a correct anchorage to the plant elements.  3. Storage of reserve food material.  4. Synthesis of plant growth regulators.  There area unit in the main three kinds of roots.  1. Tap root-  It originates from radicle.  Example- herbaceous plant, turnip, and carrots.  2. Fibrous root-  It originates from the bottom of the state.  Example- wheat and padd...

Salivary glands

Detail study of Salivary glands In this page- - Salivary glands   -  Parotid glands -  Submandibular or submaxilary glands -  Sublingual glands - Composition and function of saliva Salivary glands  Salivary gland is an exocrine gland. It releases a secretion of saliva in oral cavity. It is important to clean mouth and keep moist the mouth and pharynx. when the food s entered into the mouth the tactile receptors sense it and promote salivary glands . Even when we think about the food the salivary secretion increase from glands. Saliva lubricates, dissolves and starts chemical breakdown of the food material. The salivary glands present in the mouth and tongue. There are some minor salivary glands including labial, buccal and palatal glands present in lips, checks and palate and lingual glands in the tongue. Most of the saliva is secreted by major salivary glands . There are 3 pairs of major salivary glands 1. Parotid glands 2. Submandibular or submaxilary gla...

Detail study of human tooth

Teeth The study of tooth is known as odontalogy. There are a number of teeth present at the side of oral cavity. Each of the teeth is embedded in a socket of the bone of jaw in thecodent type of attachment. Tooth eruption starts by 6-8 month of age. The central incisors appear first. Human have diphyodont type of dentition thus they develop 2 sets of teeth, one is temporary or milk teeth and another is permanent teeth. The temporary teeth in child is also known as milk teeth. There are 20 number of temporary or milk teeth. The milk dentition starts from 6 months and complete by nearly 2 years of age. The teeth of milk dentition are of 3 types- 1. Incisor 2. Canine 3. Molar The premolar teeth are absent in temporary teeth. The temporary or milk teeth are replaced by permanent teeth between 6-12 years. An adult human has 32 permanent teeth. The permanent teeth are of 4 types- 1. Incisors- For cutting and biting food 2. Canines- For tearing the food 3. Premolar- For chewing and grinding t...

Detail study of tongue

Detail study of tongue  Tongue The floor of mouth cavity is a large, muscular, glandular, sensory tongue which is other wisely known as lingua or glossa. It helps in injection, mastication, tasting, swallowing and speech. It contains different types of papillae which can sense the taste, texture and temperature of the food perfectly. There is a fold of mucus membrane under surface of tongue . The upper surface & the lateral surface of tongue is covered by different papillae . Papillae The tongue is covered with numerous membrane at its upper and lateral surface. It may contain receptor for gustation which contain taste buds or receptor for touch which increases fraction between tongue and food or may contain some lingual glands which secrete mucus and watery fluid which contain lingual lipase. 4 Types of papillae There are several types of papillae on the basis of their structure and function. Circumvallate papillae - There are 12 large Circumvallate papillae present at...