Question

What is the plant tissue that is responsible for new growth?

Answer 1

Plants, for the most part, keep growing throughout their lives. Plants, like other multicellular creatures, grow by a combination of cell division and growth. Cell division (mitosis) increases the number of cells, whereas cell expansion increases cell size, auxins is the main hormone responsible for cell elongation in phototropism and gravitropism.

Complete answer:
Meristematic tissues are plant tissues that are made up of actively dividing cells. Meristematic tissues are divided into two categories. The first is the root/shoot apical meristem, which is located on the root/shoot apex and is responsible for plant primary growth (lengthening), and the second is the lateral meristem, which is responsible for plant secondary growth or expansion in girth.

The meristem is essential for plant cell growth and healing. Meristem is a form of plant tissue that is made up of undifferentiated cells that can proliferate and develop indefinitely.

Apical meristems are found in the apex, or tip, of roots and buds, and they allow roots and stems to grow longer and leaves and flowers to differentiate. Roots and stems lengthen when the meristem adds tissue “behind” it, propelling itself deeper into the ground (for roots) or into the air (for stems) (for stems). The apical meristem of a single branch will frequently become dominant, limiting the growth of meristems on other branches and resulting in the formation of a single trunk.

Protoderm produces new epidermis, ground meristem produces ground tissue, and procambium produces new xylem and phloem. Apical meristems differentiate into three basic types of meristem tissue that correspond to the three types of tissue: protoderm produces new epidermis, ground meristem produces ground tissue, and procambium produces new xylem and phloem. These three forms of meristem are referred to as primary meristems because they allow for primary growth in length or height.

Secondary meristems allow woody plants to expand in diameter (secondary growth). Secondary growth does not occur in herbaceous plants. Both forms of secondary meristems are called cambium, which means "exchange" or "changing." Secondary xylem (towards the centre of the stem or root) and phloem (towards the exterior of the stem or root) are produced by the vascular cambium, which increases the diameter of the plant. This process creates wood and helps trees grow strong trunks. Between the epidermis and the phloem, the cork cambium replaces the epidermis of roots and stems with bark, of which one layer is cork.

Note:-
Woody plants can grow in two different ways. Apical meristem tissue at the terminals of roots and shoots mediates primary growth, which is difficult to depict effectively in cross-sectional diagrams. The diameter of a stem or root is increased by secondary growth; vascular cambium adds xylem (inward) and phloem (outward), while cork cambium replaces epidermis with bark.