Anas Zoology

What are Lipids? A lipid is a class of organic compound which is a fatty acid or its derivative. They are insoluble in water but soluble in organic solvent. Major lipids in cell membrane are: Phospholipids  Cholesterol 1) Phospholipids: The lipid substances containing phosphorous and fatty acids are called phospholipids. There are different types of phospholipids present in cell membrane, they are as follows: Aminophospholipids Phosphatidylinositol Sphingomyelin Phosphatidylserine Phosphatidylcholine Phosphatidylglycerol Phosphatidylethanolamine The phospholipid molecules are arranged in two layers in cell membrane. A phospholipid molecule consist of two parts: head portion and tail portion. The head portion is made up of phosphate group and a glycerol atom and tail portion is made up of two fatty acid chains. Head portion is polar and hydrophilic (Strong affinity for water). The tail portion is non polar and hydrophobic (repelled by water/water fearing). Structure of Phospholipid The

White-Eared Bulbul ( Pycnonotus leucotis ) The White-Eared Bulbul is a member of Pycnonotidae family. Distribution: It is found in south-western Asia from India to the Arabian Peninsula. Identification: It has a brownish-grey body. The tail is relatively long, starting off black and ending in white tips. The head is black, but the area around its cheeks is white. The vent is bright yellow. Conservation Status: Least Concern (LC) White-Eared Bulbul Realted Posts: Scarlet Skimmer:  https://anaszoology.blogspot.com/2022/08/scarlet-skimmer-blogpost-2.html

What is DNA Barcoding? It is a technique use to identify animals, plants and microbes. A short section of DNA from a gene is used to identify the species. The short section of DNA which is used is called DNA Barcode. Dr. Paul D.N. Hebert is the founder of DNA barcoding. The gene region which is used for animal groups is Cytochrome- C oxidase I gene abbreviated as CO-1. Procedure: Take the tissue from the specimen to extract the DNA. Isolate the barcode region. Multiply the isolated DNA using PCR. Then it is sequenced The sequence obtained is placed in BOLD database (Barcode of Life Data system). It is a reference library of DNA barcodes which can be used to identify unknown specimens. Advantages: Useful in identifying species where morphological techniques are not enough. Provide evidence in poaching cases.   Related Articles: DNA Fingerprinting:  https://anaszoology.blogspot.com/2022/08/dna-fingerprinting.html Applications of DNA Fingerprinting:  https://anaszoology.blogspot.com/2022/

The stratified epithelium tissue consist of two or more layers of cells.  An epithelium tissue consist of cells that form membranes, which cover and line the body surfaces and glands.  The stratified epithelium tissue can be further classified in 4 types: Stratified Squamous Epithelium Stratified Cuboidal Epithelium Stratified Columnar Epithelium Transitional Epithelium 1) Stratified Squamous Epithelium: Description: There are several layers of cells which are cuboidal to columnar in shape. The apical cells are squamous and basal cells are cuboidal or columnar. Location: Forms superficial layer of skin (Keratinized form), lining of mouth, oesophagus, part of epiglottis and also covers the tongue. Function: Protection (against microorganisms and water loss) 2) Stratified Cuboidal Epithelium: Description: Several layer of cells in which the cells are cube shaped in both the apical surface and basal surface. Location: Pancreatic duct, Sweat glands. Function: Protection, absorption and sec

What are Liverworts ? They are thought to be the simplest of all the existing groups of land plants. They are found mainly in damp shaded habitats. They come in two forms: flat and ribbon-like. They are traditionally classified with mosses and hornworts in a group of ancient plants known as bryophytes. Liverworts have some unique features that sets them apart from other two. Their rhizoids are single celled. Snakeskin Liverwort ( Conocephalum conicum ) The name C. conicum refers to the cone shaped archegoniophore, which bear sporangia. It is found worldwide on streamside rocks and in other moist places. It is the most common liverwort in northern hemisphere. It is also found in open woodlands. It grows upto 20 cm long. Snakeskin liverwort is ribbon-shaped liverwort. It has a glossy upper surface with minute translucent chambers.

The simple epithelium tissue consist of a single layer of cells. An epithelium tissue consist of cells that form membranes, which cover and line the body surfaces and glands. The simple epithelium tissue can be further classified into 4 types: Simple Squamous Epithelium Simple Cuboidal Epithelium Simple Columnar Epithelium Pseudostratified Columnar Epithelium Simple Squamous Epithelium: Description: Single layer of cells with a centrally located nucleus. The cells are flat. Location: Lines the heart, blood vessels, bowman's capsule, air sacs of lungs and inner surface of the eardrum (tympanic membrane). Function: Filtration, diffusion and osmosis. Simple Squamous Epithelium Simple Cuboidal Epithelium: Description: Single layer of cells with a centrally located nucleus. The cells are cube shaped. Location: Surface of ovary, anterior surface of eye lens, lines the kidney tubules, found in the ducts of pancreas. Function: Secretion and absorption. Simple Cuboidal Epithelium Simple Col

An amino acid contains an amino group (-NH2) as well as a carboxyl group (-COOH). The carboxyl group is acidic (proton donor) and amino group is basic (proton acceptor). Therefore amino acids are amphoteric in nature. (Amphoteric compounds are those compounds which can act both as an acid or a base).  At low pH the carboxyl group accepts a proton and becomes uncharged so the overall charge on the molecule is positive.  At high pH the amino group loses its proton and becomes uncharged so the overall charge on molecule is negative. The pH at which the molecule carries no electrical charge is called the isoelectric point. At this point the amino acids exist as a dipolar ion or Zwitterion. A Zwitterion is a molecule with no electrical charge because it contains equal number of both positively and negatively charged ions.                         Low pH                                                                                                             High pH Related Articles: