Tag: botany

Questions Related to botany

State whether the following statements are true or false.
Azotobacter is a heterotrophic nitrogen fixing bacterium.

botany the living world archaebacteria the three domains of life classification of microbes

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

Nitrogen fixing is seen in heterotrophic bacteria live in the soil and fix significant levels of nitrogen, species like Clostridium, Bacillus, Azotobacter are called nitrogen-fixing bacteria.

So, the correct option is 'True'.

Bacteria which are found in marshy areas and among the flora of cattle rumen are called

botany the living world archaebacteria the three domains of life classification of microbes

  1. Acidophiles

  2. Thermophiles

  3. Methanogens

  4. Thermoacidophiles

Show answer
Correct Option: C
Explanation:

Methanogens are microorganisms that produce methane as a metabolic byproduct in hypoxic conditions. They are prokaryotic and belong to the domain of archaea. They are common in wetlands, where they are responsible for marsh gas, and in the digestive tracts of animals such as ruminants and humans, where they are responsible for the methane content of belching in ruminants and flatulence in humans. In marine sediments the biological production of methane, also termed methanogenesis, is generally confined to where sulfates are depleted, below the top layers. Moreover, the methanogenic archaea populations play an indispensable role in anaerobic wastewater treatments. Others are extremophiles, found in environments such as hot springs and submarine hydrothermal vents as well as in the "solid" rock of the Earth's crust, kilometers below the surface.

So the correct option is 'methanogens'.

Choose the correct answers from the alternatives given.
Facultative anaerobes:

botany the living world archaebacteria the three domains of life classification of microbes

  1. require a constant supply of oxygen

  2. are killed in an oxygenated environment

  3. do not always need oxygen

  4. are photosynthetic but do not give off oxygen

Show answer
Correct Option: C
Explanation:

A facultative anaerobe is an organism that makes ATP by aerobic respiration if oxygen is present, but is capable of switching to respiration if oxygen is absent.

So, the correct option is 'do not always need oxygen'.

State whether the following statements are true or false.
Methanogens are among the most recently evolved monerans.

botany the living world archaebacteria the three domains of life classification of microbes

  1. True

  2. False

Show answer
Correct Option: B
Explanation:

Monera is the unicellular organism's having a prokaryotic cellular structure, these are microorganisms that evolve methane gas are prokaryotic and belong to the domain of archaea, methanogenic archaea are found in the digestive tracts of human beings along with ruminants, termites, and humans.

So, the correct option is 'false'.

Grafting is not successful in monocots but is successful in dicots because they have

botany reproduction in angiospermic plants artificial vegetative propagation common modes of vegetative propagation vegetative propagation asexual modes of reproduction

  1. Vascular bundles arranged in a ring

  2. Cambiurti for secondary growth

  3. Vessels with elements arranged end to end

  4. Cork cambium

Show answer
Correct Option: B
Explanation:

Grafting is not successful is monocots but is successful in dicots because monocots lack cambium tissue which forms secondary growth. The cambium possesses the ability to form secondary xylem and phloem. It is present in dicots. In case of grafting, it is very important that the plant should form primary and secondary tissue for its survival. So, it take place only in dicots.

So, the correct answer is option B.

........... is the most convenient and cheap method of artificial vegetative propagation.

botany reproduction in angiospermic plants artificial vegetative propagation common modes of vegetative propagation vegetative propagation asexual modes of reproduction

  1. Grafting

  2. Budding

  3. Cutting

  4. Micropropagation

Show answer
Correct Option: C
Explanation:
Cutting is the most convenient and cheap method of artificial vegetative propagation because it doesn't require any skilled trained technique and it is not affected by contamination. On the other hand, the technique like grafting and budding requires skilled hand while micropropagation is highly sensitive to contamination and requires skilled hand.
Grafting is a horticulture technique where the living detached portion of the plant are used to regenerate the growth. 
Budding is a type of asexual reproduction which do not involve fusion of gametes. A new organism develops from an outgrowth or bud due to cell division at one particular site. The bud remains attached to the parent plant and separates after it gets mature. It leaves a scar at the point of separation. 
Cutting is a technique where the vegetative part is used for the propagation of plant. Cuttings are meristematic in nature so it can easily grow into a new plant.
Micropropagation is the process of multiplication and maintenance of genetically modified or hybrid plant. 
So, the correct answer is option C.

Micropropagation production of

botany reproduction in angiospermic plants artificial vegetative propagation common modes of vegetative propagation vegetative propagation asexual modes of reproduction

  1. True to type plants

  2. Haploid plants

  3. Somatic hybrids

  4. Somaclonal plants

Show answer
Correct Option: A
Explanation:
Micropropagation is the process of production of similar plants or clones. It is also used to provide a sufficient number of plantlets for planting from a stock plant which does not produce seeds or does not respond well to vegetative reproduction. The step of micropropagation includes:
1) The plant which needs to be propagated is chosen.
2) The plant part which has to be used as an explant is chosen. It can be the pollen, leaf, stem etc of the stock plant.
3) The explant is surface sterilized.
4) Culture the explant on a nutrient media.
5) After growth of root and shoot, it undergoes hardening treatment where it is grown under temperature available on fields to prepare them for growth.
6) In the final stage of plant micropropagation, the plantlets are removed from the plant media and transferred to the soil.
So, the correct answer is option A.

Identify the correct statement

botany reproduction in angiospermic plants artificial vegetative propagation common modes of vegetative propagation vegetative propagation asexual modes of reproduction

  1. Because of marked climatic variations, plants growing near the sea shore do not produce annual rings

  2. The age of the plant can be determined by its height

  3. Grafting is difficult in monocot plants as they have scattered vascular bundles

  4. Healing of damaged tissue is because of activity of sclerenchyma cells

Show answer
Correct Option: C
Explanation:
Grafting is a horticulture technique where the living detached portion of the plant are used to regenerate the growth. One plant is selected for its roots and this is called the stock or rootstock. The other plant is selected for its stems, leaves, flowers, or fruits and is called the scion. 
Grafting is not possible in monocots as they lack cambium and the joining of vascular tissues between the scion and rootstock donot take place and the vascular bundles are scattered.
So, the correct answer is option C. 

In grafting, stock is

botany reproduction in angiospermic plants artificial vegetative propagation common modes of vegetative propagation vegetative propagation asexual modes of reproduction

  1. Stem of desired variety

  2. Bud of desired variety

  3. Part of rooted plant

  4. Part to be grafted

Show answer
Correct Option: C
Explanation:
Grafting is a horticulture technique where the living detached portion of the plant is used to regenerate the growth. One plant is selected for its roots and this is called the stock or rootstock. The other plant is selected for its stems, leaves, flowers, or fruits and is called the scion. The joining of scion and stalk is known as inosculation. The technique is mostly used in an asexual mode of reproduction. 
So, the correct answer is option C.

Plants with poor root system are propagated through

botany reproduction in angiospermic plants artificial vegetative propagation common modes of vegetative propagation vegetative propagation asexual modes of reproduction

  1. Layering

  2. Leaf cuttings

  3. Stem cuttings

  4. Grafting

Show answer
Correct Option: D
Explanation:

Plants with poor root system are propagated through grafting. Grafting is a horticultural technique whereby tissues of the plant are joined so as to continue their growth together. The two plants are selected, one with good roots called rootstock and another with good flowers, fruits, leaves or stem called scion. The scion contains the desired genes to be duplicated. The plants with poor roots but with the desired  quality of other products are used as scion and grafted on plants with good mature roots.

Thus, the correct answer is option D.