Question

A mature angiosperm that bears only one leaf is
(a)Welwitschia
(b)Monophyllaea
(c)Rafflesia
(d)Betula

Answer 1

Angiosperms are that group of plants that bear sexual organs known as flowers and have protected ovules. Protected ovules mean that the ovules are covered by an ovary wall which will then become seeds that are covered by the fruit.

Complete answer:
A mature angiosperm that beras only one leaf is Monophyllaea singularis. It produces a huge macro cotyledon that is borne on a long petiole. The inflorescence of many small flowers is scattered along the petiole and midrib of this leaf. The special characteristic of this one leaf plant is that the leaf keeps growing bigger for as long as the plant is living. It is theorized that this is because this plant is a hybrid of a normal leaf and a shoot meristem. It is commonly found growing in the limestone regions of Southeast Asia.

Additional Information: Let us look at the other plants mentioned in the options:
Welwitschia: Welwitschia is a gymnosperm plant that is endemic to the Namib desert within Namibia and Angola. It is also known as tree tumbo and it produces two cotyledons after seed germination.
Rafflesia: Rafflesia arnoldii is commonly known as a corpse lily as it produces a very strong odor of decaying flesh. It is endemic to the rainforests of Sumatra and Borneo and is known for producing the largest individual flower on Earth.
Betula: Betula consists of thin leafed, hardwood trees that are deciduous in nature. They are commonly known as birch. They are found in the Northern Hemisphere with temperate and boreal climates.
So, the correct option is ‘ Monophyllaea ’.

Note: -The main plant body of angiosperms is sporophytic in nature and it is differentiated into stems. roots and leaves.
-The vascular system of angiosperms has vessels and companion cells in their xylem and phloem respectively.
-Endemic species are those species that are found in only one geographic location and nowhere else.