Tissues
A tissue is a group of similar cells that work together to perform a specific function. This Class 9 chapter classifies plant tissues (meristematic and permanent, simple and complex) and animal tissues (epithelial, connective, muscular and nervous), and explains what each type does. It complements the cell chapter by moving from single cells to organised tissues.
Learning objectives
- Define a tissue and explain why multicellular organisms need tissues.
- Classify plant tissues into meristematic and permanent.
- Distinguish simple and complex permanent tissues.
- Identify the four types of animal tissues.
- State the functions of each tissue type.
Key concepts
Meristematic tissue
Meristematic tissue consists of actively dividing cells responsible for growth in plants. It is apical (at tips, increasing length), lateral (increasing girth) or intercalary (at the base of leaves and internodes).
Permanent plant tissues
Permanent tissues are formed from meristematic tissue and have lost the power to divide. Simple permanent tissues include parenchyma (storage), collenchyma (flexible support) and sclerenchyma (hard support). Complex tissues include xylem (water transport) and phloem (food transport).
Animal tissues
Animals have four tissue types: epithelial (covering and protection), connective (joining and support, e.g. blood and bone), muscular (movement) and nervous (carrying impulses).
Muscular and nervous tissues
Muscular tissue is of three kinds — striated (voluntary), smooth (involuntary) and cardiac (heart). Nervous tissue is made of neurons that quickly carry messages throughout the body.
Key definitions
- Tissue
- A group of similar cells performing a specific function together.
- Meristematic tissue
- Plant tissue of dividing cells responsible for growth.
- Xylem
- Complex plant tissue that conducts water and minerals.
- Epithelial tissue
- Animal tissue that covers body surfaces and lines organs.
Solved examples
Q1. Which plant tissue is responsible for the increase in the length of a plant?
Solution: Apical meristem, found at the tips of roots and shoots, increases the length of the plant.
Q2. Name the tissue that transports food in plants.
Solution: Phloem, a complex permanent tissue, transports food (translocation).
Q3. Which animal tissue carries messages around the body?
Solution: Nervous tissue, made of neurons, rapidly carries impulses throughout the body.
Common mistakes to avoid
- Confusing xylem (water) with phloem (food).
- Calling blood a fluid only — it is a connective tissue.
- Mixing up the three muscle types (striated voluntary vs smooth involuntary).
- Thinking permanent tissues can divide — they have lost that ability.
Tissues — MCQ Quiz
10 questions with instant feedback. Use number keys 1–4 to answer.
A group of similar cells doing the same function is a:
Practice questions
Short answer
Name the three types of simple permanent tissue in plants.
Parenchyma, collenchyma and sclerenchyma.
What is the function of epithelial tissue?
It covers and protects body surfaces and lines internal organs.
Which tissue is responsible for movement in animals?
Muscular tissue.
Long answer
Describe the four types of animal tissues and their functions.
Epithelial tissue covers and protects body surfaces and lines organs. Connective tissue (blood, bone, cartilage, ligaments) joins, supports and transports. Muscular tissue (striated, smooth, cardiac) brings about movement. Nervous tissue, made of neurons, receives and transmits impulses, coordinating the body's responses.
Differentiate between meristematic and permanent plant tissues.
Meristematic tissue is made of small, actively dividing cells with dense cytoplasm and no large vacuoles; it brings about growth. Permanent tissue is derived from meristematic tissue, has cells that no longer divide, and carries out specific functions such as support (sclerenchyma) or transport (xylem, phloem).
HOTS (Higher Order Thinking)
Why are the cells of meristematic tissue said to have no vacuoles?
They are actively dividing and need their full volume and energy for division; large vacuoles (for storage) would not suit cells whose job is rapid growth.
The husk of a coconut is made of which tissue, and why is it tough?
It is made largely of sclerenchyma, whose cells have thick, lignified walls that make the tissue hard and protective.
Quick revision
Revision notes
- Tissue = group of similar cells with a common function.
- Plant: meristematic (dividing) vs permanent (simple: parenchyma/collenchyma/sclerenchyma; complex: xylem/phloem).
- Animal: epithelial, connective, muscular, nervous.
- Xylem → water; phloem → food; blood = connective tissue.
Key takeaways
- Meristems grow the plant; permanent tissues do specialised jobs.
- Remember blood and bone are connective tissues.
- Three muscle types: striated, smooth, cardiac.
Frequently asked questions
What is a tissue?
A group of similar cells that work together to perform a particular function.
What is the difference between xylem and phloem?
Xylem transports water and minerals; phloem transports food made in the leaves.
What are the four types of animal tissue?
Epithelial, connective, muscular and nervous tissue.