Understanding Root Anatomy

Examine the functions of roots in plants. Identify the parts of a root. Differentiate the two major types of root systems. Evaluate the health of a root system.

What are the functions of a plant’s roots? The roots anchor the plant to the ground and support the above ground part of the plant. The roots store food that has been made through photosynthesis. This food can be used later when a plant needs it to grow or survive.

What are the functions of a plant’s roots? Aeration The exchange of gases Closely linked to healthy roots high percentage of pores in soil provides good aeration

What are the functions of a plant’s roots? The roots need to be constantly growing in order to stay healthy. When roots are weak or diseased, the whole plant has difficulties.

What are the functions of a plant’s roots? Soil moisture plays a significant role in root system health: Available water Water that can be absorbed by the plant roots Unavailable water Thin film of water that binds tightly to the soil particles Cannot be used by the plants Water-holding capacity The ability of soils to hold water.

What are the parts of a root? Primary root First structure to emerge from the seed. Most important root in the whole root system

What are the parts of a root? Secondary roots Other roots branching out from the primary root New cells develop at the tip of the root Can be easily damaged Protected by a root cap Epidermis Skin cells on the surface of the root Where the water and minerals enter the root through osmosis and diffusion Root hairs Elongated epidermis cells Greatly increase the surface area of the root

What are the two types of root systems? Taproot system A root system composed of one main primary root and many secondary roots branching off Many dicot plants have taproot systems Examples of taproot include radishes, beets, and carrots

What are the two types of root systems? Fibrous root system A system that has no dominant primary root but is made of many primary and secondary roots of similar size Typically on monocot plants Examples: grasses, pansy, many annual flowers

What are the two types of root systems?

What does a healthy root system look like? A healthy root system is white or nearly white in color and smells fresh. If roots are black, brown, or dark orange and smell rotten or sour, the root system is having some problems. Although a plant growing outside has a majority of roots in only the top two feet of soil, a plant in a pot should have its roots evenly dispersed throughout the soil in the pot.