Test: Roots, Stems and Leaves - 1 - NEET MCQ

The stem is the ascending part of the axis bearing branches, leaves, flowers and fruits. It develops from the plumule of the embryo of a germinating seed. It bears nodes and internodes.
Plumule is the future shoot of a plant, as radicle is the future root of the plant.

Hence, the correct option is A.

NCERT Reference: Topic “THE STEM” of chapter Morphology of Flowering Plants 
NCERT Line: The stem is the ascending part of the axis bearing branches, leaves, flowers, and fruits. It develops from the plumule of the embryo of a germinating seed.

Root hairs in plants have a large surface area and are surrounded by water, soil and nutrients and due to large surface area root hairs absorb water for the growth of plants.

Hence, the correct option is A.
NCERT Reference: Topic “Regions of the Root” of chapter Morphology of Flowering Plants.
NCERT Line: These root hairs absorb water and minerals from the soil.

When the placenta is axial and the ovules are attached to it in a multilocular ovary, the placentation is said to be axile, as in china rose, tomato and lemon. In these plants, the ovules are attached to a central column in the ovary, allowing for the development of multiple chambers within the ovary, each containing ovules.
NCERT Reference: Topic “Placentation” of the chapter "Morphology of Flowering Plants" of NCERT.
NCERT Line: The arrangement of ovules within the ovary is known as placentation. The placentation are of different types namely, marginal, axile, parietal, basal, central and free central.

Grass is the correct option because veins on the lamina run parallel to one another is called parallel venation. It is characteristically found in monocot plants and grass is a characteristic of monocot plant.

Hence, the correct option is B.
NCERT Reference:  Topic “Venation” of chapter Morphology of Flowering Plants of NCERT 
NCERT Line: The arrangement of veins and the veinlets in the lamina of the leaf is termed venation.

• The characteristic type of venation in most monocotyledonous plants is "parallel venation."
• In this pattern, veins run parallel to each other within the leaf lamina.

Hence the correct option is " C " 
NCERT Reference: Topic -  "Venation "Morphology of Flowering Plants" of NCERT.
NCERT Line: When the veins run parallel to each other within a lamina, the venation is termed as parallel. Leaves of dicotyledonous plants generally possess reticulate venation, while parallel venation is characteristic of most monocotyledons.

• The Blade, or lamina, is the broad, flat part of the leaf. Photosynthesis occurs in the blade, which has many green food-making cells.
• The leaf is attached to the stem by the leaf base and may bear two lateral small leaf-like structures called stipules.
• The petiole helps hold the blade to light. Long thin flexible petioles allow leaf blades to flutter in the wind, thereby cooling the leaf and bringing fresh air to the leaf surface. 

Hence, the correct option is C.
NCERT Reference: Topic “THE LEAF” of chapter Morphology of Flowering Plants.
NCERT Line: The lamina or the leaf blade is the green expanded part of the leaf with veins and veinlets. 

The placenta is attached to the developing seed near the hilum. It is the scar located near the edge where seed breaks from stalf of funicules i.e., connecting the seed with the fruit wall and placenta.

Hence, the correct option is D.

NCERT Reference:  Topic “The structure of flower" of chapter Morphology of Flowering Plants
NCERT Line:  The hilum is a scar on the seed coat through which the developing seeds are attached to the fruit.
 

• In a hypogynous flower, the gynoecium occupies the highest position.
• The superior ovary is present in a hypogynous flower.
• In epigynous flower, the gynoecium is the bottom-most whorl. China rose is an example of a hypogynous flower.

NCERT Reference: Topic “The Flower” of chapter "Morphology of Flowering Plants" of NCERT.
NCERT Line:  In epigynous flowers, the margin of the thalamus grows upward enclosing the ovary completely and getting fused with it, the other parts of the flower arise above the ovary.

• In monocotyledonous seeds, the outer covering of the endosperm separates the embryo from the rest of the seed by a proteinaceous layer called the aleurone layer.
• The aleurone layer is a specialized tissue that contains proteins and enzymes involved in the mobilization of nutrients from the endosperm to support the growth of the developing embryo during germination.

NCERT References: Topic “The Seed” of the chapter "Morphology of Flowering Plants" of NCERT.
NCERT Line: The outer covering of the endosperm separates the embryo by a proteinous layer called the aleurone layer.

• Phylloclade is found in Opuntia and Cactus. Phylloclades and cladodes are modified branches. They are flattened structures that are photosynthetic and resemble leaf-like branches. 
• They store water inside the tissue. The leaves are modified into spines. 

Hence, the correct option is D.

NCERT Reference: Topic “Modifications of Stem” of chapter Morphology of Flowering Plants.

• The root is covered at the end by a thimble like structure called root cap. Meristematic tissue helps in the growth of plants. Meristematic cells when mature form the so called permanent cells.
• Root hairs increase the surface area which helps in increasing the levels of water absorption.

Hence the correct answer is " A " 

A flower containing only stamen is called staminate.

Based on symmetry, flowers are classified into actinomorphic, zygomorphic and asymmetric flowers.

Flowers that possess radial symmetry is said to be actinomorphic flower.

Canna is an asymmetric flower.

Venation refers to the pattern of arrangement of veins in the leaflet. The monocots have their leaf veins arranged in a parallel manner with respect to each other whereas in case of dicots the leaf veins are reticulated or muzzled up.

Hence, the correct option is B.
NCERT Reference: Topic “Venation” of chapter Morphology of Flowering Plants. 

• A modified stem that is flattened and capable of unlimited growth is called as phylloclade. It carries out photosynthesis. It is a xerophytic adaptation. Leaves are changed into spines in xerophytic structures called phylloclade.
  Examples include Opuntia.
• Opuntia is a xerophytic plant, in which leaves are modified into spines to reduce the rate of respiration.
• A modified stem capable of limited growth is called as cladode. It carries out photosynthesis. Examples include Ruscus, Asparagus species.
• Phyllode is a petiole modified into a leaf-like structure.

Hence, the correct option is C.

NCERT Reference: Topic “Modifications of Stem” of chapter Morphology of Flowering Plants.

Reticulate venation is a characteristic of dicots and parallel venation is of monocots. But few exceptions are also seen in this generalization: parallel venation is also found in dicot plants.
Example: Calophyllum, corymbium , etc., and reticulate venation is also found in monocot plants such Alocasia, Smilax, etc. 

Hence, the correct option is B.