Describe the amoeba.Here please explain its structure (if possible include about their contractive vacuole), movement and how it captures and digests food.

Expert Answers
pohnpei397 eNotes educator| Certified Educator

An amoeba is composed of cellular fluid called cytoplasm which is divided into two parts.  These are ectoplasm (a membrane-like outer layer) and endoplasm.  Within the endoplasm are cavities called vacuoles which help with digestion or which contract to move water into or out of the amoeba, depending on what is needed (contractive vacuole).

Amoebas move by forming pseudopods (little extrusions) and then having the rest of the cytoplasm flow into those structures.  They capture food in much the same way.  After being surrounded, the food is brought into the vacuoles that are responsible for digestion.

krishna-agrawala | Student

Amoeba is a simple one cell organism that varies in size from about 0.25 millimeters to 2.5 millimeters across.

an amoeba is a shapeless mass of living matter. It is mostly composed of protoplasm, which is a jelly like material found in all living cells. The protoplasm is contained by a thin flexible covering or membrane. Water and gases can pass through this membrane. Within the protoplasm the amoeba contain a nucleus which is composed of special type of protoplasm.

The amoeba moves by changing its shape. It forms a finger like projection (called pseudopod) in the direction it wants to move and subsequently all the matter within the membrane is pushed in to this projection. This is like completing one step forward.

Amoebas eat tiny living organisms and dead or decaying matter. It eats by surrounding its food with pseudopodia and and then finally engulfing it.In this way the food gets inside the cell. The section of cell that contains food is called vacuole, which floats in the protoplasm till the food is digested. All undigested foo is forced out of the cell.

Amoebas reproduce by splitting itself apart in two. In this process of reproduction, the nucleus is split first, following which each of the two new nucleus are surrounded by protoplasm of the original amoeba, and the two parts begin to separate, forming an increasingly narrower neck or thin passage between the two parts, till the passage is completely closed. At this point the two cell detach from each other forming two new cells.