‘NCERT Solutions for Class 9 Science Chapter 6‘ PDF Quick download link is given at the bottom of this article. You can see the PDF demo, size of the PDF, page numbers, and direct download Free PDF of ‘Ncert Class 9 Science Chapter 6 Exercise Solution’ using the download button.
NCERT Class 9 Science Textbook Chapter 6 With Answer PDF Free Download
Chapter 6: Tissues
From the last chapter, we recall that all living organisms are made of cells. In unicellular
organisms, a single cell performs all basic functions.
For example, in Amoeba, a single cell carries out movement, intake of food and respiratory gases, respiration, and excretion.
But in multi-cellular organisms, there are millions of cells. Most of these cells are specialized to carry out a few functions. Each specialized function is taken up by a different group of cells.
Since these cells carry out only a particular function, they do it very efficiently.
In human beings, muscle cells contract and relax to cause movement, nerve cells carry messages, and blood flows to transport oxygen, food, hormones, waste material, and so on.
In plants, vascular tissues conduct food and water from one part of the plant to other parts. So, multi-cellular organisms show division of labor.
Cells specializing in one function are often grouped together in the body. This means that a particular function is carried out by a cluster of cells at a definite place in the body.
This cluster of cells, called a tissue, is arranged and designed so as to give the highest possible efficiency of function.
Blood, phloem, and muscle are all examples of tissues. A group of cells that are similar in structure and/or work together to achieve a particular function forms a tissue.
6.1 Are Plants and Animals Made Are Plants and Animals Made of the Same Types of Tissues? of Same Types of Tissues?
Let us compare their structure and functions. Do plants and animals have the same
structure? Do they both perform similar functions?
There are noticeable differences between the two. Plants are stationary or fixed – they don’t move. Most of the tissues they have are supportive, which provides them with structural strength.
Most of these tissues are dead since dead cells can provide mechanical strength as easily as live ones, and need less maintenance.
Animals on the other hand move around in search of food, mates, and shelter. They consume more energy as compared to plants. Most of the tissues they contain are living. Another difference between animals and plants is in the pattern of growth.
The growth in plants is limited to certain regions, while this is not so in animals. There are some
tissues in plants that divide throughout their life.
These tissues are localized in certain regions. Based on the dividing capacity of the tissues, various plant tissues can be classified as growing or meristematic tissue and permanent tissue.
Cell growth in animals is more uniform. So, there is no such demarcation of dividing and non-dividing regions in animals The structural organization of organs and organ systems is far more specialized and localized in complex animals than even in very complex plants.
This fundamental difference reflects the different modes of life pursued by these two major groups of organisms, particularly in their different feeding methods.
Also, they are differently adapted for a sedentary existence on one hand (plants) and active locomotion on the other (animals), contributing to this difference in the organ system design.
|No. of Pages||12|
|PDF Size||920 KB|
NCERT Solutions Class 9 Science Chapter 6 Tissues
1. What is tissue?
A tissue is defined as a cluster of cells that are similar in structure and work together to perform a particular function.
2. What is the utility of tissues in multicellular organisms?
The use of tissues in multicellular organisms is to provide structural and mechanical strength as well as to allow division of labor.
3. Name types of simple tissues.
The types of simple tissues are as follows:
4. Where is apical meristem found?
In plants, apical meristem is typically found at:
- The tip of the shoot
- The root of the plant
5. Which tissue makes up the husk of coconut?
The Sclerenchymatous tissue, which is a type of permanent tissue makes up the husk of the coconut. These tissues cause the plant to become stiff and hard. The cells of this tissue are dead and their cell walls are thickened because of the presence of lignin.
6. What are the constituents of phloem?
The phloem constitutes of the following four elements, they are:
➢ Sieve tube
➢ Companion cells
➢ Phloem parenchyma
➢ Phloem fibers
7. Name the tissue responsible for the movement of our body.
Two tissues jointly are responsible for the movement of our body, namely:
➢ Muscular tissue
➢ Nervous tissue
9. Give three features of cardiac muscles.
The cardiac muscles are specialized tissues that are evolved to pump blood throughout the body.
The following are the features of the cardiac muscles:
➢ They are cylindrical in shape.
➢ Striated muscle fibers.
➢ They are uninucleated and branched.
➢ These muscles are involuntary in nature.
10. What are the functions of areolar tissue?
Areolar tissues are typically observed in animals. They are connective tissues and are found in between skin and muscles.
They are also located around blood vessels and nerves and are present in the bone marrow. The space inside the organs is filled with these tissues. They support the delicate internal organs and assist in tissue repair in case of damage.
TTissues NCERT Textbook With Solutions PDF Free Download