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An overview of cell

  A typical plant cell, has a distinct cell wall as its outer boundary and just within it is the cell membrane . Cells that have membrane bound nuclei are called eukaryotic whereas cells that lack a membrane bound nucleus are prokaryotic . in both prokaryotic and eukaryotic cells,  a semi- fluid matrix called cytoplasm occupies the volume of the cell. The cytoplasm is the main arena of cellular activities in both the plant and animal cells. various chemical reactions occurs in it to keep the cell in the living state., Besides the nucleus, the eukaryotic cells have other membrane bound distinct structures called organelles like the endoplasmic reticulum (ER), the golgi complex, lysosomes, microbodies . the prokaryotic cells lack such membrane bound organelles. Ribosomes are non-membrane bound organelles found in all cells - both eukaryotic as well as prokaryotic cells. Within the cell, ribosomes  are found not only in the cytoplasm but also within the two organelles chloroplast (in plan
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Cell theory

In 1838, Matthias Schleiden , a German botanist , examined a large number of plants and observed that all plants are composed of different kind of the cell which form the tissue of the plants . at about the same time Theodore Schwann  (1839) , a British Zoologist ,studied different type of animal cell and reported that cells had a thin outer layer which is today known as the plasma membrane . He also conclude, based on his studies on plant tissue, that the presence of the cell wall is a unique character of the plants cells. Schwann proposed the hypothesis that the bodies of animals and plants are composed of the cells and products of cells . Schleiden & Schwann together formulated the cell theory . this theory however , did not explain as to how new cells were formed . Rudolf Virchow (1855) first  explained that cells cells divided and new cells are formed from pre-existing cells (Omnis cellula-e-cellula). He modified the hypothesis of Schleiden and Schwann  to give the cell theo

What is cell

 All organisms are composed of cell. Some are composed of a single cell and are called unicellular organisms while others, like us, composed of many cells, are called multicellular organism . unicellular organism are capable of (1) independent  existence and (2) performing the essential functions of life . Anything less than a complete structure if a cell does not ensure independent living . Hence, cell is the fundamental structure and functional unit of all living organisms. first cell was discovered by - ROBERT HOOKE in thin slice of cork. Anton von Leeuwenhoek first saw and describe a living cell . Robert Brown later discovered the nucleus .

What is cell

  NCERT  ask this question to you and give some difficult answer of it . let us simplify :-                             A cell is the structural and functional unit of life.                          A cell is defined as the smallest basic unit of life that is responsible for all of the life`s processes.

Digestion and Absorbtion

Digestion is the complex process by which your body breaks down the food you eat into nutrients that can be absorbed and used for energy, growth, and repair. It begins in the mouth and continues in the stomach, small intestine, and large intestine. Here's a simplified overview of the digestive process: Ingestion: The process starts when you eat food. Chewing in the mouth breaks down the food into smaller particles and mixes it with saliva. Mechanical and Chemical Digestion in the Mouth: Saliva contains enzymes like amylase that begin breaking down carbohydrates in the food. Chewing also helps break down the food mechanically. Swallowing: The tongue pushes the partially digested food (called bolus) to the back of the throat, and then it's swallowed, moving it into the esophagus. Esophagus: The esophagus is a muscular tube that carries the bolus of food from the mouth to the stomach through a coordinated process called peristalsis. Stomach: The stomach is a J-shaped organ that co