Question

Examine the figures (A-D) given above and select the right option out of 1-4, in which all the four structures A, B, C, and D are identified correctly.

| A| B| C| D
---|---|---|---|---
1.| Sucker| Seta | Megaspore mother cell| Gemma Cup
2. | Rhizome| Sporangiophore | Polar cell | Globule
3.| Runner | Archegoniophore| Synergid | Antheridium
4. | Offset| Antheridiophore | Antipodals| Oogonium

A. 4
B. 3
C. 2
D. 1

Answer 1

The subaerial stems of the aquatic plants that help in propagation are known as the offsets. In Marchantia both male and female plants are separated and they are distant from each other. In an embryo sac, there is an 8-nucleated and 7-celled condition present. Moreover, the male and female sex organ of the Chara is present on the same plant.

Complete answer: Let us look at all the figures that are given to us one by one.

The given figure is of Water Hyacinth or Eichhornia. Water hyacinth has short, horizontal branches that produce the cluster of leaves above and the bundle of roots below. These branches are known as offsets. These are the subaerial stems that take the help of the ground or surface for spreading. Offsets help in vegetative reproduction. The breaking of offsets helps in propagation.
Therefore, the given structure A is an offset.

The given figure is of Marchantia. Marchantia is a dioecious plant. The male sex organ in Marchantia is known as the antheridium. The sex organs are borne over the special branches called the gametophores. The gametophyte of the male thallus is known as the antheridiophore. Therefore, the given structure B is an antheridiophore.

The given figure is of the female gametophyte of the Flowering plants or the Angiosperms. The female gametophyte consists of the Micropylar end and a Chalazal end. The micropylar end consists of two synergids and an egg cell. The chalazal end consists of three Antipodal cells. There is a central cell that consists of two Polar nuclei.
Therefore, the given structure C is an Antipodal cell.

The given figure is of Chara. Chara is a green alga. It has highly specialized sex organs. The female sex organ is known as the Oogonium or the Nocule. It is found on the upper position of the adaxial surface of the short lateral branch on almost every node. The oogonium consists of a single cell only.
Therefore, the given structure D is an Oogonium.
Thus, based on the above information we can conclude that the correctly matched pairs are, A – Offsets, B – Antheridiophore, C – Antipodal, and D – Oogonium. These pairs match with set 4.
Hence, the correct answer is option (A).

Note: Water hyacinth is also known as the Terror of Bengal. Water hyacinth was introduced in India by the Britishers. It has very beautiful flowers and the shape of the leaves. However, it is a very invasive aquatic weed. It spread in all the water bodies in the Bengal, and throughout India. Water hyacinth drains the oxygen from the water causing the death of the aquatic flora and Fauna. It killed the fishes in the water due to which food was scarce in Bengal. It was therefore called the Terror of Bengal.