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ANIMAL NUTRITION (Digestive system)

Short answer type  questions Q1. Name two bile pigments.  Ans. Biliveridin and bilirubin.  Q2. Name two enzymes which take part in the digestion of proteins in our body.  Ans. Pepsin, Trypsin.  Q3. How is fat digested in the humans?  Ans. By the activity of the enzymes lipases.  Q4. State one function of each of the following in human body: i) Vitamin A  ii) Vitamin C iii) Vitamin D iv) Vitamin K Ans. i) Vitamin A: Controla normal epithelial structure and growth; essential for the formation of the visual pigment rhodospin, which aids night vision.  ii) Vitamin C: Concerned with the metabolism of connective tissue and the production of strong skin, essential for collagen synthesis.  iii) Vitamin D: Controls calcium and phosphorus metabolism, important in bone and tooth formation.  iv) Vitamin K: Essential for prothrombin synthesis in the liver, a necessary factor for the blood-clotting mechanism.  Q5. State the one importance and one deficiency symptom of the following in our body: i) F
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Plant tissues

Short answer type questions Q1. Give an example of secondary mesristem.  Ans. Vascular cambium of dicot root.  Q2. What makes the root's apical meristem sub-terminal?  Ans.   Presence of root cap makes the root's apical meristem sub-terminal.  Q3. What type of tissue constitutes calyptrogen?  Ans. Metistematic tissues.  Q4. List the parts of periderm.  Ans. Phellogen(cork cambium), phelloderm(secondary cortex) and phellum(cork).  Q5. What does fascicular cambium give rise to?  Ans. Secondary vascular tissues.  Q6. What is most significant role of peticycle?  Ans. The formation of lateral roots and helps in secondary growth.  Q7. What is the most significant role of fusiform initials?  Ans. Differentiate into secondary xylem and pholem.  Q8. Mention the most significant role of bulliform cells.  Ans. To reduce transpiration by rolling of the leaf during dry seasons.  Q9. What is a bicollateral vascular bundle?  Ans. A vascular bundle having both external and internal phloem is c
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Classification of Porifera

 The phylum porifera has been subdivided into three classes based primarily on the nature of the skeleton.  The three classes are as follows- CLASS 1. CALCAREA This classes comprises calcareous sponges as their skeleton on spicules are made up of calcium carbonate. (L.calcarius=limy, Gr., sponges=sponge)  Characters 1. Members of these class are similar in size extending up to 15 cm in length and may be solitary or colonial. 2. The body shape is usually cylindrical or vase-like.  3. The osculum is narrow, terminal and fringed with bristles.  4. The skeleton consists of separate calcareous spicules which may be monaxon, triradiate or tetraradiate.  5. The collar cells  are comparatively of larger size.  6. The canal system is sycon, ascon, or leucon  type.  7. The colour of the body is white or dull brown.  8. The exclusively marine and occur in shallow coastal water.  Class Calcarea is divided into two order - Order 1. Homocoela 1. The body is small, cylindrical and thin walled without
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Phylum - Porifera

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➡Introduction (L., porus=pore, ferre=to bear)  The name Porifera to this phylum was given by Robert E Grant (1936). Porifera means pore bearers. This is phylum includes a group of animals which bears numerous minute pore throughout the surface of the body and are usually called  sponges.  ⁍ General characters 1. All sponges are aquatic,mostly marine but a few are freshwater.  2.They are multicellular organism with cellular level of body organisation without forming tissue or organs.  3. They are sessile, solitary or colonial.  4. They are asymmetrical or radially symmetrical bodies.  5. They body is cylindrical, tubular or vase-like.  6. The body wall is diploblastic with outer dermal epithelium and inner gastric epithelium  with a gelatinous non-cellular mesenchyme in between.  7. The body surface bears numerous minute pores that is Ostia for the ingress of water.  8. They possess peculiar canal system through which water current flows drawing food and oxygen inside the body and carr
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DIGESTIVE SYSTEM

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➡ Digestive system of human beings consists of alimentary canal or gut  and some accessory organs  like teeth, salivary gland, gall bladder, pancreas and liver.  ➡ Alimentary canal • It is a coiled, muscular, continuous tube running through the central body cavity extending from the mouth to the anus. It is about 30 feet long.  (a) mouth   (b) oral (buccal) cavity  (c) pharynx (d) oesophagus (e) stomach (f) small intestine (g) large intestine (h) rectum and anus ⁍ Mouth • Daily secretion of saliva in the mouth is 1 to 1.5 litre. Saliva is acidic in nature. Saliva contains ptyalin  enzyme which acts on cooked starch changing them into sugar maltose.  • There are three pairs of salivary glands viz. parotids, submaxilliary(sub mandibular) and sublingual.  ⁍  Buccal (oral) cavity •  The mouth leads into oral cavity that has two lateral walls (cheeks), an anterior roof (hard palate), a posterior roof (soft palate) and a pair of jaw (upper maxilla and lower mandible).  • The buccal cavity is
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