Tag: absorption of water from the soil

A. Wolffia is a free-floating thallus, so its body does not contain roots.

Root hair the large thread like structure arises from the epidermis layer of the root. These basically arise from the region of elongation. Root hairs are rarely branched. These are exogenous in origin because arise from the superficial layer of the epidermis. Root hairs are unicellular.

Thus, the correct answer is 'False.'

They persist until the epidermis separates from the root, although hairs composed of living cells are usually found only on the tip 1 cm. of the roots. Hairs of adventitious roots growing in the soil are most commonly or always unicellular and look very much the same as hairs of many other roots.

Primary roots continue to grow to form a secondary root system as the secondary root system is large and extends deep into the ground.

Respiratory roots are non-photosynthetic and non-green in nature. They are seen in plants growing in marshy regions and in aquatic plants. They are found in wheat. They are also called as breathing roots. Fasciculated roots are modified adventitious roots. They are arranged in fascicles.

Plant roots have diploid cells (2n) which in this case has 16 chromosomes.

Some roots, called adventitious roots, arise from an organ other than the root—usually a stem, sometimes a leaf. They are especially numerous on underground stems, such as rhizomes, corms, and tubers, and make it possible to vegetatively propagate many plants from stem or leaf cuttings.

Root hairs are unicellular extensions of epidermal cells found in the zone of maturation, where they are responsible for water and mineral absorption.

Safranin is a common biological stain used to highlight cell walls and nuclei in plant tissue samples like onion root tips.

Roots exhibit negative phototropism, meaning they grow away from the light source, while stems exhibit positive phototropism.