Content text Ex-1 Anatomy of Flowering Plants(Q-Ans-Sol).pdf
30 ANATOMY OF FLOWERING PLANTS EXERCISE – 1: Basic Objective Questions Introduction to Plant Tissues 1. Tissues are classified into two main groups, namely, meristematic and permanent tissues based on- (a) Position and location (b) Function, position, and location (c) Whether the cells are capable of dividing or not (d) Structure, function, position, and location Ans. (c) Sol. A tissue is a group of cells having a common origin and usually performing a common function. Tissues are classified into two main groups, namely, meristematic and permanent tissues based on whether the cells being formed are capable of dividing or not. Meristematic tissues have the ability to divide and form new cells. The cells of the permanent tissues do not generally divide further. Meristematic Tissues 2. Growth in plants is largely restricted to specialized regions of active cell division called (a) Meristem (b) Cambium (c) Primordium (d) Permanent tissue Ans. (a) Sol. Meristem is a localized region comprising the meristematic tissues which are capable of cell division, and hence growth is largely restricted to this region. There is active cell division in this area which leads to the growth of the plant. 3. Both apical meristems and intercalary meristems are _____ meristems. (a) Primary (b) Secondary (c) Lateral (d) Both (b) and (c) Ans. (a) Sol. Apical meristems and intercalary meristems together constitute the primary meristem. These are meristematic tissues which appear in early stages of development and form the plant body. They help in increasing the height of the plant. On the other hand, lateral meristems are formed later and produce secondary tissues like fascicular cambium, cork cambium, etc. 4. The growth of the roots and stems in length with the help of apical meristem is called (a) Primary growth (b) Lateral growth (c) Secondary growth (d) Intercalary growth Ans. (a) Sol. Primary growth includes growth due to apical meristem and intercalary meristem. Apical meristems are present at the ends of root and shoot systems and help in the elongation of the plant whereas, the intercalary meristems are present in other regions of the plant body but not at the apices. Lateral meristem increases the girth of the plant and contributes to secondary growth. 5. Intercalary meristem is a derivative of (a) Promeristem (b) Primary meristem (c) Lateral meristem (d) Secondary meristem Ans. (b) Sol. Intercalary meristem is a derivative of primary meristem which occurs only in monocot stems. It is commonly found at the base of leaves, above the nodes (e.g., grasses), or below the nodes (e.g., mint). It helps in the elongation of plant organs and regenerate parts removed by the grazing herbivores. 6. Intercalary meristem produces (a) Secondary growth (b) Primary growth (c) Apical growth (d) Secondary overgrowth Ans. (b) Sol. Intercalary meristem is present only in monocots stem at the base of nodes, internodes and leaf blades and is responsible for the increase in the length of the plant organs. They are responsible for the replacement of the tissues lost to the grazing herbivores. 7. Length of petiole increases by the activity of (a) Apical meristem (b) Lateral meristem (c) Intercalary meristem (d) All the above Ans. (c)
32 ANATOMY OF FLOWERING PLANTS Ans. (d) Sol. Intrafascicular vascular cambium and interfascicular cambium along with cork cambium increase the girth of the plant axis by producing secondary tissues. 12. Which meristem helps in increasing girth? (a) Lateral meristem/cambium (b) Intercalary meristem (c) Primary meristem (d) Apical meristem Ans. (a) Sol. Lateral meristem or the cambium helps in increasing the girth due to this, the epidermis layers get broken and need to be replaced to provide new protective cell layers. 13. Vascular cambium and cork cambium are examples of (a) Apical meristem (b) Lateral meristem (c) Intercalary meristem (d) Promeristem Ans. (b) Sol. Lateral meristem is a secondary meristem and is formed in later developmental stages of a plant. They form the tissues during the secondary growth of plants. As vascular cambium and cork cambium are formed later and are not present in primary stages of development they cannot be produced by apical, intercalary or promeristem. These three are primary meristems. 14. Interfascicular cambium is (a) Primary meristem (b) Secondary meristem (c) Abnormal meristem (d) None of these Ans. (b) Sol. Primary growth of the plant is due to the primary meristem present in the root and shoot apex. Interfascicular cambium is responsible for the increase in the girth of the stems and roots (secondary growth). They are formed from de-differentiation from permanent tissues and hence are called secondary meristems. 15. Read the following statements and find out the incorrect statement. (a) There are structural similarities and variations (differences) in the external morphology and internal structure of the larger living organisms in both plants and animals. (b) Plants have cells as the basic unit which is organized into tissues and in turn, the tissues are organized into organs. (c) A tissue is a group of cells having a common origin and usually performing different functions. (d) Axillary buds are present in the axils of leaves and are capable of forming a branch or a flower. Ans. (c) Sol. The tissue is defined as a group of cells from the same origin with a similar structure, organized to perform a common function. 16. Assertion: Both apical meristem and intercalary meristem are primary meristems. Reason: Both of these meristems appear early in life of a plant and help in the formation of the primary plant body. (a) If both assertion and reason are true and reason is the correct explanation of assertion. (b) If both assertion and reason are true but reason is not the correct explanation of assertion. (c) If the assertion is true but the reason is false. (d) If both assertion and reason are false. Ans. (a) Sol. Growth in plants is largely restricted to specialized regions of active cell division called meristems (Gk. Meristos: divided). Plants have different kinds of meristems. The meristems which occur at the tips of roots and shoots and produce primary tissues are called apical meristems. They produce growth in length. The meristem which occurs between mature tissues is known as intercalary meristem. Intercalary meristems are commonly located at the bases of leaves, above the nodes (e.g., grasses) or below the nodes (e.g., mint). Intercalary meristems help in elongation of the organs. Both apical meristems and intercalary meristems are primary meristems because they appear early in life of a plant and contribute to the formation of the primary plant body. 17. Assertion: Fascicular vascular cambium, interfascicular cambium and cork-cambium are examples of lateral meristems. Reason: These are responsible for producing the secondary tissues. (a) If both assertion and reason are true and reason is the correct explanation of assertion.