Chapter 9, Problem 6STP

Summary Introduction

Introduction :

Cilia are small, slender, hair-like structures extend from the surface of many types of eukaryotic cells. They are primitive in nature are found in large numbers on the surface of the cell. In humans, these are found in the respiratory epithelium of the respiratory tract. They are involved in movement of substances.

Answer to Problem 6STP

Correct answer :

The correct answer is option (A) cilia.

Explanation of Solution

Explanation/justification for the correct answer :

Option (A) cilia. The structure projecting from cells in the given diagram are cilia because they are short sized and large in number. Thus, the correct answer is an option (A).

The explanation for the incorrect answer :

Option (B) flagella. The structure projecting from cells in the given diagram are not flagella because they are large in size and less in number, may single or two. Thus, this is an incorrect option.

Option (C) microfilaments. Microfilaments are protein filaments present in the cytoplasm of eukaryotic cells that form part of the cytoskeleton. The structure projecting from cells in the given diagram are not microfilaments.Thus, this is an incorrect answer.

Option (D) villi. Highly folded into finger-like projections present in the inner epithelial lining of the small intestine are called villi. The structure projecting from cells in the given diagram are not villi. Thus, this is an incorrect answer.