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In 1832 "Robert Brown" discovered nucleus. It is the essential part of the cell. A definite nucleus is absent in prokaryotic cell. Instead of it a DNA molecules is present. It is called by “Prokaryotic cell". Ex: Bacteria. Definite nucleus is present. It is covered by nuclear membrane.…
In the cytoplasm of the cell complex membrane bounded system is present. It was called cytoplasmic vacuolar system by "Sacz & De robertis" in 1975. This system contains endoplasmic reticule, nuclear envelop, and Golgi. Endoplasmic Reticulum (E.R.) was first observed by "Porter, Claude, Fullam" in 1945. Occurrence: In…
In the animal and plant cells clusters of fat filled structures are present. They are called Golgi apparatus or complex. In 1898 Camillo Golgi' recognised it in the nerve cell of the owl. The Golgi complex of invertebrates is called dictyosome. Occurence: Golgi complex is seen in all eukaryotic…
Lysosome: These are first observed in liver cells. They are 1.5 to 2 milii micron in size These are single membrane bounded structures. They were first called pericanalicular-dense bodies. "Christian De Duve" called them lysosomes in 1955. They were named as lysosomes because they contain hydrolytic enzymes. Occurence:…
DEFINITION OF MITOCHONDRIA: Mitochondria are center for cellular respiration. It converts chemical energy into kinetic energy. Information About Mitochondria In 1857 Kolliker observed mitochondria and called them as sarco-somes. Flemming called them as Fila. Altmann in 1890 called them as Bioplasts. Benda gave the name mito-chondria. Porter…
The cytoplasm of the animal cell is bounded by a thin limiting membrane called "Cell membrane". Nageli and Cramer called this membrane as cell membrane in 1855. In 1931 "Plowe" named this as plasmalemma. Modem cell biologists prefer to call it plasma membrane (According to De Robertis). Danielli &…
Cell is a fundamental, structural and functional unit of living organism. The science which deals with cells and their organelles is called cell-biology. The term cell was first used by Robert Hooke in 1665. He described the cell first as cella which means hollow space. Robert Hooke observed cells in…
Serial No. Feature Prokaryotic Cell Eukaryotic Cell 1. Nuclear envelope absent present 2. DNA single, circular and naked more than one and combined with proteins 3. Chromosome single multiple 4. Nucleolus absent present 5. Division amrtosis mitosis or meiosis 6. Ribosomes 70S(50S+30S scattered in cytoplasm 80S(60S+40S) Found attached to ER…
The cells which lack true nuclear membrane are called prokaryotic cells. Blue green algae, bacteria are the examples for prokaryotic cells. Prokaryotic cells lack chloroplasts mitochondria, Golgi complex and endoplasmic reticulum. Prokaryotic cells are simple and primitive cells. In blue green algae cell shows a cell wall,…
Cell Biology (Gr., kytos-hollow vessel or cell, logos-to discourse) is a biological science which deals with the study of cells. The cell itself can be regarded as the vital unit of organisms. 'Aristotle' and 'Paracelsus' concluded that "all animals and plants, however, complicated are constituted by few elements which are…
When Blood is mixed with a solution of potassium cyanide, potassium ferricyanide, and Drabkin’s solution, the erythrocytes are lysed by producing evenly disturbed hemoglobin solution. Potassium ferricyanide transforms hemoglobin into methemoglobin, and methemoglobin combines with potassium cyanide to produce hemiglobincyanide (cyanmethemoglobin). This method is optional for estimation of hemoglobin and…
When blood is mixed with an acid solution, the hemoglobin converts into the brown-colored acid hematin. The acid hematin is then diluted with distilled water till the color of the acid hematin matches that of the brown glass standard. The hemoglobin is estimated by reading the value directly from the…
HEMOGLOBIN Hemoglobin is composed of heme (iron + protoporphyrin) and globin polypeptide chains. It is present in the red blood cells of all vertebrates except Channichthyidae (the family of fish: white-blooded fish also called crocodile fish found in southern South America and the Southern Ocean around Antarctica). It carries oxygen…
Red Cell Indices Red cell indices are mean cell volume (MCV), mean cell hemoglobin (MCH), and mean cell hemoglobin concentration (MCHC). They are also called as “absolute values”. They are derived from the values of hemoglobin, packed cell volume (PCV or hematocrit), and red cell count. Red cell indices are…
Reticulocytes Reticulocytes are young or juvenile red cells released from the bone marrow into the bloodstream and that contain remnants of ribonucleic acid (RNA) and ribosomes but no nucleus. After staining with a supravital dye such as new methylene blue, RNA appears as blue precipitating granules or filaments within the…
Reticulocytes are young or juvenile red cells released from the bone marrow into the bloodstream and that contain remnants of ribonucleic acid (RNA) and ribosomes but no nucleus. After staining with a supravital dye such as new methylene blue, RNA appears as blue precipitating granules or filaments within the red…