Problem 151 - Objective Biology for NEET

Question

Both cilium and flagellum emerges from centriole like structure which is called (a) Basal granules (b) Basal bodies (c) Basal lamina (d) Basal ganglion

Step-by-Step Solution

Answer

The correct answer is (b) Basal bodies

Step 1: Understanding the query

This step involves understanding what the question is asking. In this case, a specific characteristic about the cilium and flagellum is being questioned, which is the structure from which they both emerge.

Step 2: Applying biology knowledge

The second step necessitates calling on your knowledge of biology to recollect the correct term. Both cilium and flagellum emerge from a centriole-like structure, which is known in cellular biology as 'Basal bodies'.

Key Concepts

Cilium and Flagellum

Cilia and flagella are hair-like structures that protrude from the surface of many eukaryotic cells. While they appear similar, cilia are typically shorter and more numerous on cells, functioning like oars to move either the cell itself or fluid and particles across the cell's surface. Flagella, on the other hand, are longer and usually number one or two per cell, acting like propellers to drive cells forward in a whip-like motion.

Cilia are essential for various physiological processes, such as the movement of mucus in the respiratory tract, which helps clear debris and pathogens. Flagella play a significant role in cell motility and are crucial for the reproduction of some organisms, where they assist in the propulsion of sperm cells.

Both cilia and flagella are composed of microtubules arranged in a '9+2' structure, with nine pairs of microtubules surrounding two central microtubules. This arrangement is enclosed by the cell membrane, extending the cytoskeleton and allowing these structures their characteristic movements.

Basal Bodies

Basal bodies are the 'centriole-like' structures that serve as the anchoring point for cilia and flagella. Acting as a foundation, they organize the microtubule assembly of cilia and flagella and are crucial for their proper function.

Located just beneath the cell membrane, basal bodies are made up of a '9+0' arrangement of microtubule triplets—nine sets forming a ring without the central pair found in cilia and flagella. An important aspect of basal bodies is their role in initiating the construction of these appendages by providing a template that guides the growth of the microtubule shaft.

Beyond structural support, basal bodies also have a role in signaling pathways and cell cycle control. Dysfunctions in basal bodies can lead to diseases known as ciliopathies, which can affect multiple systems in the body, including the respiratory system and fertility.

Cell Structure

The cell is the fundamental unit of life, and its structure is intricately designed to carry out life-sustaining functions. Eukaryotic cells, which include plant, animal and fungi cells, possess a variety of organelles each with specialized roles.

The nucleus serves as the control center housing DNA, the blueprint of biological information. Mitochondria are the powerhouses of the cell, generating energy through respiration. The endoplasmic reticulum and Golgi apparatus are involved in the synthesis and packaging of proteins, whereas lysosomes are responsible for waste processing and degradation.

The cell's cytoskeleton provides mechanical support, maintains cell shape and enables cellular motion through components like microtubules and actin filaments. The previously mentioned cilia and flagella are part of this dynamic network. Understanding the entirety of cell structure is critical for grasping the complex interactions and functions occurring in biological systems.