Tag: importance of plants

Questions Related to importance of plants

The leaves of gymnosperms are well-adapted to withstand extremes of temperature, humidity and wind, because of which of the following features?

  1. Needle like leaves

  2. Thick cuticle

  3. Sunken stomata

  4. All of these


Correct Option: D
Explanation:

Conifers have a number of xerophytic characters such as needle-like (e.g., Pinus), scale-like {e.g., Thuja) or small and leathery leaves {e.g., Araucarias), thick cuticle, sclerenchymatous hypodermis and sunken stomata to reduce transpiration. They are, thus, well adapted to tide over the winter period when the soil becomes frozen and availability of water is very little.

So the correct option is D.

Ephedrine (medicine) is obtained from __A, it is effective medicine in _B_ :-

  1. A : Gnetum, B : Fever

  2. A : Ephedra, B : Asthma

  3. A : Pinus, B : Chilgoza

  4. A : Claviceps , B : Cough


Correct Option: B
Explanation:

Ephedra is an alkaloid chemical compound traditionally obtained from the plant Ephedra sinica. Ephedrine is a medication and stimulant. It is often used to prevent low blood pressure during spinal anesthesia. It has also been used for asthma, narcolepsy, and obesity but is not the preferred treatment. It is of unclear benefit in nasal congestion.


So, the correct option is 'Option B'.

The  wood produced by gymnosperms is commercially known as

  1. hardwood

  2. sapwood

  3. logwood

  4. softwood


Correct Option: D
Explanation:
 Wood is secondary xylem consisting largely of dead cells involved in the transport of water and minerals as well as support. Plants grow in length because of the elongation of cells produced by terminal (apical) meristem. Most of the cells formed by meristems mature to form epidermis, general matrix tissue (parenchyma), and primary xylem and phloem. In herbaceous plants all of the vascular tissue is produced by apical meristems. In plants that subsequently become woody, a cambium layer forms between the primary xylem and phloem cells. The cambium is a lateral (expanding in width) meristem, capable of dividing to produce additional xylem toward the inside of the stem and additional phloem to the outside. Gymnosperms (softwood) are composed primarily of tracheids, long cells that conduct water primarily through openings in their side walls. Gymnosperms contain fewer kinds of cells than does angiosperm wood, and tends to be comparatively uniform.
So the correct option is 'softwood'.

The giant Redwood tree (Sequoia sempervirens) is a / an _______________.

  1. Angiosperm

  2. Free fern

  3. Pteridophyte

  4. Gymnosperm


Correct Option: D
Explanation:

Sequoia sempervirens is a gymnosperm. It is the sole living species of genus Sequoia. Its common names include coast redwood, California redwood. It is an evergreen, long-living monoecious tree.

So the correct option is D.

Cedarwood oil is obtained from the heartwood of

  1. Cedrus

  2. Thuja occidentalis

  3. Tagetes

  4. Juniperus


Correct Option: D
Explanation:

The oil obtained from Juniperus virginiana, is cedar wood oil and is used in laboratory for microscopic work. Today, cedar oil is often used for its aromatic properties, especially in aromatherapy. Cedar oil is used as an insect repellent, both directly applied to the skin and as an additive to sprays, candles and other products.

From which of the following plants is a medicine for respiratory disorders obtained?

  1. Bambusa

  2. Sesamum

  3. Ephedra

  4. Pinus


Correct Option: C
Explanation:

Ephedra (Ephedra sinica) is an herb, that has been used in traditional chinese medicine for more than 5,000 years, primarily to treat asthma or bronchitis. Ephedra is also prescribed for symptoms of cold and flu, including nasal congestion, cough, fever, and chills.

Sago comes from

  1. Calamus ritung

  2. Metroxylon rumphii

  3. Areca catechu

  4. Phoenix dactylifera


Correct Option: B
Explanation:

Sago is made with the starch extracted from the pith of an array of various tropical palm trees. Especially in Metroxylon Sagu, Rottb. Metroxylon Rumphii, Mart.

So the correct option is 'Metroxylon rumphii.'

Wood of Cedrus deodara is mainly used for making

  1. Railway sleepers

  2. Match sticks

  3. Pencils

  4. Furniture


Correct Option: A
Explanation:

Cedrus deodara is a high mountain tree that occurs in a wide range of habitats in the Himalaya. It is also knowns as Deodar and its is in great demand as building material because of its durability, rot-resistant character and good polish taking ability. Thus the correct answer is option A.

Resin got from Pinus is

  1. Hard resin

  2. Mixture of resin and latex

  3. Oleoresin

  4. Gum resin.


Correct Option: C
Explanation:
Oleoresins are pure extracts of a spice or herb. They are concentrated natural liquid flavourings that contain both volatile and non-volatile flavour components. It is mainly extracted from Pinus. It represents an inestimable and renewable source of terpenes, showing several industrial applications. 
The correct answer is 'Oleoresin'.

Select the correct one from the following

  1. Vascular tissues develop first in amphibian bryophytes

  2. Seed formation start from the pteridophyte plants

  3. Thalloid mycelium and hyphae are common in green algae.

  4. Wood of gymnosperms are durable and resistant to termites attack


Correct Option: D
Explanation:

  • Vascular tissues did not appear in bryophytes. Bryophytes are non-vascular plants. 
  • Pteridophytes do not have seeds. Seed formation, first of all, started from angiospermous plants.
  • Mycelium is the vegetative part of fungus made up of thread-like structures called hyphae.
So, statement numbers 1, 2 and 3 are incorrect.
  • The wood of gymnosperm is durable, and it is also resistant to attack by termites. So, it has a very high economic value.
Thus option D is the correct answer.