class 9 tissue lesson crossword
pls urgent
Answers
Answer:Tissues
Tissues are a group of cells that combine together to perform a particular function
Plant tissues
Plant tissues are of various types and they are made up of similar types of cells. They are different from animal tissues since there are several differences between the animal and plant cell.
Animal tissues
Animal tissues are made up of animal cells. These tissues are usually not rigid since the cells do not have cell walls.
Plant Tissues
Meristematic tissues
Meristematic tissues are seen in plants. They are primarily made up of rapidly dividing cells. They are the growing tissues of the plant.
Permanent tissues
Permanent tissues arise from the meristematic tissue and have structural and functional properties. Permanent tissue can be made up of either living or dead cells.
Differentiation
Differentiation is the process by which the meristematic tissues develop into different types of permanent tissues based on the location and requirement of the plant.
Apical meristem
Apical meristem are present on the apex of the plant shoot and root. They are rapidly growing tissues and aid in increasing the height of the plant.
Lateral meristem
Lateral meristem are present on the lateral walls of the stem. They help in the horizontal growth of the plant and increasing the stem girth.
Intercalary meristem
Intercalary meristem can be found between the nodes of the stem and the base of the leaf. They help in branching.
Simple permanent tissues
These are tissues that are made up of only one type of cells. They usually have structural role.
Complex permanent tissues
Complex permanent tissues are made by combination of different types of cells. These cells work together to perform a specific task.
Parenchyma
Parenchyma tissues are made up of loosely packed cells with thin cell walls and large intercellular spaces. They are live cells and help in support and storage. Two types; Chlorenchyma and Arenchyma.
Collenchyma
Collenchyma tissues are made up of live cells which have irregularly thickened corners and thus, have decreased intercellular spaces. They help in bending of various parts of the plant without breaking.
Sclerenchyma
Sclerenchyma tissues make up the hard and stiff parts of the plant. They are made up of dead, long and narrow cells. They almost have no intercellular space as the walls are thickened due to the presence of lignin.
Phloem
Phloem is made up of the following components – sieve tubes, companion cells, phloem parenchyma and phloem fibres. Phloem conducts food in both directions. Among all the components, phloem fibres are the only dead cells.
Xylem
Xylem is made up of the following components. The vessels and tracheids – help in conduction of water and minerals from the soil. Xylem parenchyma helps in food storage and the xylem fibres provide mechanical support.
Explanation: