Question

The smallest and lightest seed is that of
A. Lemna
B. Morus
C. Orchid
D. Wolffia

Answer 1

Hint: Seed is the embryonic plant which gets enclosed by the protective outer covering. The seed can germinate to form a new plant.

Complete Answer:
1. Lemna – Lemna is a genus of free floating aquatic plants. They are commonly called ‘duckweeds’. They belong to the family Araceae.
- These plants are rapidly growing plants and used as a model system for studies in ecology, plant biology, etc. These plants mainly grow by vegetative reproduction.
- Duckweeds are the flowering plants and can undergo sexual reproduction and produce seeds under suitable conditions.

2. Morus – Morus is also called the white mulberry. They are the fast growing small to medium sized mulberry tree. It is a genus of flowering plants belonging to the family Moraceae.

3. Orchid – Orchids belong to the family Orchidaceae. They are the flowering plants, with blooms that are colourful and fragrant.
- The family Orchidaceae consist of 2800 accepted species that are distributed in about 763 genres.
- The seeds of the Orchids are the smallest and lightest seeds among all the flowering plants. The seeds of orchids are merely the size of dust.

4. Wolffia – Wolffia is a genus of only 9 to 11 species. It includes the smallest flowering plants on the Earth.
They are the aquatic plants that resemble specks of cornmeal floating on water. These plants are free floating thalli, green or yellow green coloured. These plants lack roots.

Hence, option C is the correct answer for this question.

Note: Flowering plants are also called as Angiosperms. They are the vascular plants that means they have the vascular tissue that are Xylem and Phloem. The Xylem is responsible for the transportation of water and minerals while phloem is responsible for the transportation of organic substances.