Amoeba appears as a colorless and transparent drop of jelly when viewed under a microscope. Therefore, it isn’t possible to describe its definite shape, anterior or posterior ends, dorsal and ventral surfaces. Furthermore, as Amoeba’s shape is changeable, its body can’t be divided into two comparable parts. This condition is called asymmetry. 1 mm. The body of Amoeba can be divided into two primary parts, Plasmalemma and Protoplasm. A.Plasmalemma or Plasma membrane: The body of Amoeba is covered with plasmalemma formed by the association of protein and lipid.
This membrane is extremely thin, living, semi-permeable and elastic. Functions: 1. Plasmalemma of Amoeba gives its shape. The membrane being elastic it can produce pseudopodia easily. By the process of diffusion, throughout the plasmalema, it can take oxygen and water. Cytoplasm: Without the nucleus, the rest of the protoplasm is cytoplasm. This part is thick, transparent, non-granular and contractile. Functions: 1. Ectoplasm protects the organelles inside the body. This part is semi-transparent and less viscous. The relatively thick outer part of endoplasm is called plasmagel and inner liquid part plasmasol. The granules of plasmagel usually always remain stable.
However, the granules present in plasmas show active movement. The distinction between plasmagel and plasmas is .not consistent because one can be transformed to another. Functions: 1. Endoplasm contains the organelles of the cell. Frequent change in the density of the plasma gel and plasmasol helps in producing pseudopodia. Nucleus: In the center of the endoplasm the translucent round body seen in the nucleus. There’s just one nucleus in Amoeba., The nucleus is covered by the nuclear membrane made of protein and lipid. The amount of nucleoplasm is scarce in the nucleus of Amoeba. Functions: 1. Nucleus conducts the functions of the Cell body.
Nucleus takes an active part in reproduction. Cytoplasmic organelles: Pseudopodia: From any part of the body of living Amoeba finger is continuously produced continuously. These are known as pseudopodia. Pseudopods are made of plasmalemma, ectoplasm, and endoplasm. These are unstable growths of the body and disappear soon. The anterior part of the pseudopods is round and blunt. Functions: 1. Pseudopods help in capturing food materials. They play a major part in locomotion. Pseudopods indicate the anterior part of the Amoeba during the time of locomotion. Vacuoles: There are various types of vacuoles in Amoeba. Presence of the vacuoles is an essential characteristic of Amoeba.
The nature of the formation of those vacuoles is rather simple. The vacuoles help in various physiological functions. There are 3 types of vacuoles in Amoeba. Contractile Vacuole: At the endoplasm of Amoeba some bubble like vacuoles are seen. These vacuoles are transparent and fast growing. Food Vacuole: within the body of Amoeba food vacuole is formed surrounding the food material.
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