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Q1. Describe the gynoecium of ground nut.  

Solution

In ground nut, the ovary is superior, monocarpellary and unilocular with many ovules. The gynoecium has a single style.  

Q2. Name the region of the root whose epidermal cells form root hair.

Solution

The epidermal cells of the region of maturation form root hair.

Q3. Distinguish between zygomorphic flower and actinomorphic flower.

Solution

Zygomorphic Flower Actinomorphic Flower 1. The flower can be divided into two similar halves in one particular plane. 1. The flower can be divided into two equal radial halves in any radial plane passing through the central axis of the flower. 2. Examples: Mustard, Datura 2. Examples: Gulmohar, Pea  

Q4. Explain how the stem is involved in reproduction in jasmine and Chrysanthemum.

Solution

Jasmine: A slender lateral branch arises from the base of the main axis. After growing aerially for some time, it arches down to touch the ground. Chrysanthemum: The lateral branches originate from the basal and underground portion of the main stem. It grows horizontally beneath the soil and comes out obliquely upwards to give rise to leafy shoots.

Q5. Describe the different regions of the root.

Solution

The different regions of the root are as follows: 1. Root cap: It covers the apex of roots which grow through the soil. 2. Region of Meristematic Activity: This region is a few millimetres above the root cap. The cells are thin-walled and small with dense protoplasm. The cells divide repeatedly. 3. Region of Elongation: This region is proximal to the region of meristematic activity. The cells in this region undergo rapid elongation and enlargement. This zone is responsible for the growth in length of the root. These cells gradually differentiate and mature. 4. Zone of Maturation: The zone of maturation is proximal to the zone of elongation. Its epidermal cells give rise to root hair cells which absorb water from the soil.

Q6. Write the vegetative characters of the family Fabaceae.

Solution

The vegetative characters of the family Fabaceae are as follows: 1. The stem is erect or a climber. 2. Leaves are alternate, pinnately compound or simple. The leaf base is pulvinate, stipulate and leaf venation is reticulate.

Q7. Describe the arrangement of calyx and corolla of sun hemp.  

Solution

Calyx of sun hemp:     1. There are five sepals. It is gamosepalous and shows imbricate aestivation.     Corolla of sun hemp:     1. There are five petals. It is polypetalous consisting of posterior standard, two lateral wings and two anterior petals forming a keel. It exhibits vexillary aestivation.  

Q8. State the type of root in sweet potato which stores food.

Solution

Adventitious roots in sweet potato are swollen to store food.

Q9. State the function of stem tendrils.

Solution

Stem tendrils help plants to climb.

Q10. Cite examples of non-endospermous seeds.

Solution

Examples of non-endospermous seeds are as follows: Bean, gram, pea

Q11. Explain the three types of phyllotaxy and give examples of each type.  

Solution

The three types of phyllotaxy are as follows:     1. Alternate type of phyllotaxy:     A single leaf arises at each node in an alternate manner.     Examples: China rose, Sun flower     2. Opposite type of phyllotaxy:     A pair of leaves arise at each node and lie opposite to each other.     Examples: Calotropis, Guava     3. Whorled type of phyllotaxy:     More than two leaves arise at a node and form a whorl.     Example: Alstonia  

Q12. State the three parts of the carpel.

Solution

The three parts of the carpel are ovary, style and stigma.

Q13. Name the root system found in mustard plant.

Solution

The tap root system is found in mustard plant.

Q14. What is the root cap? State its function.

Solution

The root cap is the structure which is thimble-like and covers the root apex. It protects the tender apex of the root while it makes its way through the soil.

Q15. Name the fruit which has a fibrous mesocarp.

Solution

Coconut has a fibrous mesocarp.

Q16. Define the following and give one example of each: (a) Bisexual flower (b) Unisexual flower

Solution

(a) Bisexual flower: It is a flower in which both androecium and gynoecium are present. Example: Tulip (b) Unisexual flower: It is a flower with only androecium or gynoecium. Example: Flower of papaya plant

Q17. Differentiate between marginal and axial placentation.

Solution

Marginal Placentation Axial Placentation 1. The placenta is in the form of a ridge along the ventral suture of the ovary, and ovules develop on this ridge. 1. The placenta is axial, i.e. develops on the axis, and ovules are attached to the placenta in a multilocular form. 2. Example: Pea 2. Example: Tomato  

Q18. Draw a diagram of mango indicating the arrangement of its pericarp. Describe its pericarp in short.

Solution

In mango, the pericarp is well differentiated into an outer thin epicarp, a middle fleshy edible mesocarp and an inner endocarp which is stony and hard.  

Q19. What is the significance of brightly coloured petals?

Solution

Brightly coloured petals attract insects for pollination.

Q20. What are nodes and internodes?

Solution

Nodes are the regions on the stem from which leaves develop, while internodes are the regions between two nodes.

Q21. What is aestivation? Distinguish between valvate aestivation and twisted aestivation.

Solution

Aestivation is the mode of arrangement of sepals or petals in a floral bud with respect to the other members of the same whorl. Valvate Aestivation Twisted Aestivation 1. Sepal or petals in a whorl just touch one another. They do not overlap. 1. One margin of the floral appendage overlaps the margin of the next appendage. 2. Example: Calotropis 2. Example: China rose  

Q22. Name two plants whose tap roots are modified to store food.

Solution

Carrot Turnip

Q23. Define venation.

Solution

The arrangement of veins and veinlets in the lamina of the leaf is called venation.

Q24. What are thorns? Give one example of a plant in which thorns are found.

Solution

Thorns are the modified axillary buds of the stem. Thorns are found in citrus plants.

Q25. Draw a floral diagram for Solanum nigrum.  

Solution

   

Q26. Draw a well-labelled diagram of the regions of the root tip.  

Solution

   

Q27. Name the meristem from which leaves originate.

Solution

Leaves originate from the shoot apical meristem.

Q28. State the function of root hair.

Solution

Root hair absorbs water and minerals from the soil.

Q29. What does a dot represent in a floral diagram?

Solution

A dot in the floral diagram represents the position of the flower axis with respect to the flower.

Q30. Name the two plants which have stilt roots developing from the nodes of their stems.

Solution

Maize Sugar Cane

Q31. State the functions of the stem.

Solution

Functions of the stem: 1. To spread out the branches bearing leaves, flowers and fruits. 2. To conduct water, minerals and photosynthates to different parts of the plant. 3. Modified stems perform different functions such as storage of food, protection, support, reproduction and photosynthesis.

Q32. How is fusion indicated in a floral formula?

Solution

Fusion in a floral formula is indicated by enclosing the figure in brackets.

Q33. Describe epipetalous stamens.

Solution

When the stamens are attached to the petals, they are called epipetalous stamens.

Q34. Explain the following terms: (a) Gamosepalous calyx (b) Pentamerous flower

Solution

(a) A gamosepalous calyx is one in which all the sepals are united. (b) A pentamerous flower is one in which the floral appendages are in multiples of five.

Q35. What is modification of roots? Write the modification of roots found in the following plants:     (a) Maize     (b) Carrot     (c) Banyan tree     (d) Rhizophora  

Solution

The roots in some plants are modified for support, storage of food and respiration.     (a) Maize: Stilt roots arise from the nodes of the stem to support the plant.     (b) Carrot: Roots are swollen and store food.     (c) Banyan Tree: Prop roots arise to support the tree.     (d) Rhizophora: Roots arise above the ground to obtain oxygen for respiration.  

Q36. Describe the structure of a dicotyledonous seed.

Solution

A dicotyledonous seed is covered by a seed coat.   A seed coat is made of two layers—an outer testa and an inner tegmen. There is a scar on the seed coat called hilum. Through the hilum, the developing seeds are attached to the fruit. A micropyle is the small pore present just above the hilum. An embryo is enclosed by the seed coat. The embryo has an embryonal axis and two cotyledons. The cotyledons are fleshy, and they serve as the food reserves for the developing embryo. At the two ends of the embryonal axis are the radicle and the plumule.

Q37. Explain the arrangement of flowers in racemose inflorescence.

Solution

In racemose inflorescence, the flowers grow laterally on the main axis in an acropetal succession.

Q38. Describe the structure of a monocotyledonous seed.  

Solution

The seed coat which covers the seed is membranous and fused with the cell wall.           The endosperm is bulky, and it serves as the food reserve.     The outer covering of the endosperm is a proteinous layer called the aleurone layer.     A small embryo is located in a groove at one end of the endosperm.     A large shield-shaped cotyledon called the scutellum is present.     The embryo has a short axis with the radicle and plumule.     The radicle and plumule are enclosed in sheaths called coleorhiza and coleoptile, respectively.  

Q39. Name the types of roots which originate from the base of the stem.  

Solution

Fibrous roots originate from the base of the stem.  

Q40. Define stem.

Solution

The stem is the ascending part of the axis which bears branches, leaves, flowers and fruits.