Previous Year Question
Consider the following statements.
The Taxus tree naturally found in the Himalayas.
The Taxus tree is listed in the Red Data Book.
A drug called ‘taxol’ is obtained from Taxus tree is effective against Parkinson’s disease.
Which of the statement(s) given above is/are correct?
Only 1
1 and 2
2 and 3
1, 2 and 3
Correct Answer: B
Detailed Solution
1. The Taxus tree is naturally found in the Himalayas—Correct
The Himalayan Taxus is commonly known as the Himalayan yew. Its scientific name is Taxus wallichiana. In older classifications, it was also treated as Taxus baccata subsp. wallichiana.
It is an evergreen, coniferous and slow-growing tree. It occurs naturally in the temperate forests of the Himalayas and in some montane forests of northeastern India. It has flat, needle-like leaves, while its seed is surrounded by a fleshy red covering.
2. The Taxus tree is listed in the Red Data Book—Correct
Taxus wallichiana has been included in Red Data records concerning threatened Indian plants. Its major threats include:
excessive collection of bark and leaves for medicinal use;
slow natural growth and regeneration;
forest degradation and habitat fragmentation; and
grazing and other human pressures.
Large-scale removal of bark can destroy the tree’s ability to transport water and nutrients and may kill it. Unregulated medicinal extraction has therefore been a serious threat to natural populations.
3. Taxol is effective against Parkinson’s disease—Incorrect
Taxol, whose generic pharmaceutical name is paclitaxel, is an anticancer drug; it is not a standard treatment for Parkinson’s disease.
Paclitaxel binds to and stabilises cellular microtubules. This interferes with the normal separation of chromosomes during cell division and stops the growth of cancer cells.
It is used in the treatment of breast cancer, ovarian cancer, certain lung cancers and Kaposi sarcoma, among other cancers.
Facts about Taxus and Taxol
Taxol was originally discovered in the bark of the Pacific yew, Taxus brevifolia.
Taxane compounds are present in different Taxus species, including the Himalayan yew.
Early extraction of Taxol from bark damaged or killed large numbers of trees.
Semi-synthesis, cultured cells and renewable foliage sources are now used to reduce pressure on natural trees.
Therefore, statements 1 and 2 are correct, while statement 3 is incorrect.