Test: Morphology of Flowering Plants - Assertion and Reasoning - NEET MCQ

Root cap is the terminal part of root.

In fibrous type of root system, the radicle, primary roots stops growth or becomes rudimentary, while new roots for anchorage and absorption develop from the base of the stem. This type of root formation is observed in Monocots. Therefore assertion is correct, because it is a distinguishing feature of monocots it is not found in dicots. The dicots have tap root system also called the true roots that develop from the radicle. Therefore, reason is false

So, the correct answer is 'Assertion is correct but Reason is incorrect

Ginger is horizontal in position and generally branched and producing aerial leaves or shoots above ground and adventitious roots on lower side in favourable season. Thus, shoot growth is not effected by gravity.

In plants such as Avicennia, growing in swampy areas, many roots come out of the ground and grow vertically upwards. Such roots are called pneumatophores which help to get oxygen for respiration. These roots are also known as respiratory roots.

Root is typically a non green underground cylindrical structure forming the descending axis of the plant which gives rise to endogenous branches and does not possess nodes, leaves or buds. Presence of nodes and internodes is the characteristic feature of stems.

The root cap protects the root meristem from friction of the soil particles. In the process, its outer cells are continuously peeled off and replaced by new cells formed from root meristem. In floating aquatic plants, the root apices possess finger glove-like coverings called root pockets instead of root cap.

Root pockets are present in floating aquatic plants. They act as balancers. They are structurally similar to root caps but differ from them, in the fact, that the damaged root pockets are not regenerated. Pandanus, possess multiple root caps with a number of sheaths found successfully one after the other because they are not peeled off in the absence of soil friction.

Root hair zone is 1-6 cm in length. The root hairs increase the exposed surface of the root for absorption of water and minerals.

Deep feeder tap root system has an elongated tap root which penetrates the deeper layers of the soil. It is mostly found in trees. Deep feeder tap root is also called racemose tap root system. In surface feeders, the tap root does not elongate very much. The secondary roots spread to a greater extent. Such a system is also named as cymose tap root system.

The fleshy roots are thickened like the palm of human hand. They similarly possess finger like outgrowth, e.g., Orchis. They are palmate roots. Fasciculated fleshy roots are the swollen roots or root tubers occurring in clusters.

Moniliform of beaded roots are swollen at regular intervals like beads of a necklace. Hence, the roots have the appearance of necklace. Such roots are found in Discorealata, Momordica charauter etc.

Assimilatory roots are green roots (as they contain chlorophyll) which are capable of photosynthesis. e.g., Taeniophyllum, is a leafless epiphytic orchid with thick flattened photosynthetic roots.

Epiphytes live on the surface of other plants for shelter and space only, hence are also called space parasites. Epiphytic roots possess a covering of dead spongy tissue known as velamen. They are able to absorb water from moist atmosphere, dew and rain with the help of velamen.

The zone of elongation region of a root lies behind the growing point. The cells of this region are newly formed cells which lose the power of division. They elongate rapidly. This increases the length of the root. The root hair zone represents the zone of differentiation or maturation because of different types of primary tissues differentiates or matures in this region. Some of the outer cells of this zone give rise to lateral tubular outgrowths called root hairs.

A bud is a condensed immature or embryonic shoot having a growing point surrounded by closely placed immature leaves. The largest bud is cabbage. According to their nature, buds can be vegetative, reproductive and mixed.

Stems are modified to perform different functions like storage, protection, mechanical support and photosynthesis etc. Axillary buds of stems may also get modified into woody, straight and pointed thorns.Thorns are found in many plants such as Citrus, Bougainvillea, etc. They protect plants from browsing animals and also reduce transpiraton .

Stem is usually the above-ground erect ascending part of the plant body that develops from the plumule, grows by means of a terminal bud and shows distinction of nodes and internodes. The nodes bear leaves having auxillary buds.

The pedicles or floral stacks of Artabotrys are modified into stiff curved thorns or hooks for climbing. In Antigonon, the flowers occur in bunches in the axils of scale leaves on the floral shoot. The upper floral buds develop into tendrils instead of forming flowers.

Prickles are superficial outgrowths of stem or leaves which do not possess a vascular cylinder. They can be easily pulled off. Bristles are stiff hair which become thickened due to deposition of silica or calcium carbonate.

Phyllodes do not bear leaves, branches, flowers, etc. In Parkinsonia aculeata, the rachis ends in a spine. Rachis are elongated, flattened and green to function as phyllodes. They bear small leaflets which fall off very easily.