Final answer:
The meristematic tissue, specifically the apical meristem, is responsible for the growth at the tips of roots and shoots in plants.
Step-by-step explanation:
The type of plant tissue that makes up the newly growing tips of roots or shoots is the meristematic tissue. This tissue is found in regions of the plant where active division occurs, such as root and shoot tips, which allows for elongation of the plant in these areas. The apical meristem, in particular, is a component of this meristematic tissue located at the tips of stems and roots that is responsible for primary growth, enabling a plant to extend in length. Apical meristems are vital for the plant as they provide the capability to grow upwards, seeking sunlight, and downwards, absorbing water and nutrients from the soil.