Question

Some seeds are dispersed by animals, especially spiny seeds with hooks which get attached to the bodies of animals and are carried to distant places. Examples is/are:
A. Xanthium and urena
B. Xanthium
C. Urena
D. Coconut

Answer 1

Hint: Transport of seeds from one place to another or from the flower to various places refers to seeds dispersal. Various agents can help in the dispersal of seeds such as wind, water, animals and gravity.

Complete Answer:
- Seeds are the reproductive unit of a flower which consists of embryos which can develop into a new plant on germination. Some seeds are also used as a source of food. The various parts of seeds include embryo, endosperm and a seed coat.
- The plumule in the embryo develops into the shoot whereas the radicle in the embryo develops into the root.
- Seed dispersal is a method in seed bearing plants where the seeds are spread away from the parent plants to cause germination and formation of new plants. There are various vectors which help in the dispersal of seeds such as water, wind, animals, birds and gravity.

Seed dispersal by animals:
- Some animals and birds are attracted by the bright and colourful fruits and flowers. These animals eat the fruits and suck the nectar from the flowers. While doing so, they digest the soft fruit part while the seed is excreted as their droppings in far places from the plants. For example- seeds of cherry, tomato, blackberry and apple.
- Some plants bear seeds with hooks.These seeds get attached on the furs of animals and get carried to different places. For example Xanthium and urena.
The seeds in the coconut are dispersed by water as they are adapted to float in water. The outer layer of seeds in coconut dry out leading to its floating on water.

So, the correct answer is option (A).

Note: Seeds are the reproductive units of plants which on germination give rise to new plants. They are dispersed by various vectors. Xanthium and urena seeds are adapted to be dispersed by the hooks and furs of animals.