Problem 1 - Objective Biology for NEET

Question

Which of the following is a simple form of movement? (a) Streaming of protoplasm in amoeba (b) Ciliary movement in paramecium (c) Flagellar movement in Euglena (d) All of these

Step-by-Step Solution

Answer

(d) All of these

Step 1: Understand streaming of protoplasm in amoeba

This refers to the shifting flow of cytoplasm within the amoeba. The amoeba changes shape as the cytoplasm streams into a pseudopodium (an extended 'foot'), and then the rest of the amoeba follows.

Step 2: Analyze ciliary movement in paramecium

This refers to the coordinated movement of numerous tiny hair-like structures (cilia) that cover the body of a paramecium. The cilia beat in coordinated strokes to achieve movement.

Step 3: Consider flagellar movement in Euglena

This refers to the movement caused by a long whip-like structure (flagellum) that protrudes from the cell body of Euglena. The flagellum beats in a wave-like manner to propel the Euglena through its watery environment.

Key Concepts

Streaming of Protoplasm

Streaming of protoplasm is a fascinating form of movement employed by amoebas. Protoplasm is the jelly-like material that makes up a cell, and in amoebas, it flows in a manner that allows these single-celled organisms to move and change shape. This movement is also known as "amoeboid movement." The process involves the amoeba extending a part of its cell, called a pseudopodium, which looks like a temporary foot.

Here's how it works:

• The protoplasm within the amoeba shifts its position, pushing the cell membrane outward to form a pseudopodium.
• Once the pseudopodium is extended, the rest of the cell's protoplasm streams into it, pulling the rest of the cell along with it.
• This movement allows the amoeba to explore its environment and capture food.

Amoeboid movement is crucial for the survival of these organisms as it enables them to navigate their surroundings to find sustenance and avoid unfavorable conditions.

Ciliary Movement

Ciliary movement is a type of locomotion seen in organisms like paramecium. These creatures are covered with tiny hair-like structures called cilia. Each cilium beats in a coordinated fashion to propel the organism forward. This type of movement is incredibly efficient, allowing paramecium to navigate their aquatic environments with ease.

Here’s a closer look at the process:

• Cilia beat in a rhythmic pattern, often resembling the coordinated waves of a rowing boat.
• This collective movement creates a water current that propels the paramecium in the desired direction.
• The cilia can beat faster or slower, adjusting the speed of movement to suit environmental conditions.

Ciliary movement is not only used for locomotion but also helps in feeding by directing food particles towards the organism’s mouth opening. This versatile movement mechanism serves multiple purposes for the paramecium, enhancing its ability to thrive.

Flagellar Movement

Flagellar movement is primarily observed in Euglena and other flagellate organisms. The flagellum is a long, tail-like structure that extends from the cell body, and it plays a crucial role in movement. Unlike cilia, there is typically only one or a few flagella per cell.

• Flagella whip back and forth in a wave-like motion, driving the organism through its watery habitat.
• This motion can be likened to a propeller, propelling the cell forward through liquid environments.
• The movement is often smooth and allows the organism to navigate towards light sources or nutrients.

Euglena, for example, utilizes this flagellar propulsion to position itself in well-lit areas ideal for photosynthesis, contributing to its energy production through photosynthetic processes. The efficiency of flagellar movement is crucial for the survival and functionality of these microorganisms.