Tag: botany

Questions Related to botany

Nepenthes (Insectivorous pitcher plant) is 

botany know the plant world closely diversity in plants types of nutrition in plants different modes of nutrition in plants

  1. Producer

  2. Consumer

  3. Both A and B

  4. None of the above

Show answer
Correct Option: C
Explanation:

Like all green plants, pitcher plants use their leaves to harness energy from the sun and make their own food; they use carbon dioxide (CO$ _{2}$) to make energy-rich carbohydrates. So, they are producers. 

However, it tends to grow on very wet soils that are very poor in nitrogen, an important element in the processes of life. Their leaves serve as traps that capture insects, secrete digestive enzymes that break down their prey, and absorb this juice into their tissues. These carnivorous traps are adaptations that allow these plants to survive and prosper in their harsh, nitrogen-poor environment. 
Hence, it is both a producer and a carnivore. 

Which statement is correct about saprophytes ?

botany know the plant world closely diversity in plants types of nutrition in plants different modes of nutrition in plants

  1. They do not possess chlorophyll

  2. They survive on other organisms

  3. They live on dead organism

  4. All of the above

Show answer
Correct Option: D
Explanation:

Saprophytes are the class of organism that have saprophytic mode of nutrition. They feed on dead living organism. They are assumed to have evolved from green plants but have lost their chlorophyll during the course of evolution.

Small herbaceous plants that grow on higher plants but do not obtain their nourishment from them are called 

botany know the plant world closely diversity in plants types of nutrition in plants different modes of nutrition in plants

  1. Insectivorous

  2. Epiphytes

  3. Saprophytes

  4. Mycorrhiza

Show answer
Correct Option: B
Explanation:
A.Insectivorous plants - Plants, trap, kill and digest insects are called insectivourous plants. They grow in nitrogen
B.Epiphytic - Plants which grow on the branches of big trees for light and shelter. These plants are not connected to soil directly.
 deficient soils. So, to get nitrogen the kill and digest the insects.
C.Saprophytic - Organisms, grow on the dead bodies to get food.
D. Mycorrhiza - association of fungi with roots of higher plants
So the correct option is 'epiphytes'.

One of the following is a saprophyte.

botany know the plant world closely diversity in plants types of nutrition in plants different modes of nutrition in plants

  1. Monotropa$/$ Neottia

  2. Utricularia

  3. Dionaea

  4. Nepenthes

Show answer
Correct Option: A

What is the function of germ pore?

botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

  1. Emergence of radicle

  2. Absorption of water for seed germination

  3. Initiation of pollen tube

  4. All of these

Show answer
Correct Option: C
Explanation:

One or more thin areas present in the exine of pollen grains are known as germ pores. The germ pores are apertures in the exine layer of the pollen grain where the sporopollenin is absent. The germ pore helps in the formation of the pollen tube and the release of the male gametes during fertilisation. There are usually three germ pores in dicots(tricolpate) and one in monocots(monocolpate).

In Casuarina, fertilization occurs by 

botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

  1. Chalazogamy

  2. Mesogamy

  3. Porogamy

  4. Apogamy

Show answer
Correct Option: A
Explanation:
  • Pollen tube eventually reaches the micropyle of an ovule to enter the embryo sac and for this purpose, it may follow one of the following three routes:
  • 1. Porogamy- when the pollen tube enters the ovule through the micropyle. It is common for most of the angiosperms.
  • 2. Mesogamy- when the pollen tube enters through the integuments (Cucumber) or through funiculus (Pistacia).
  • 3. Chalazogamy- when the pollen tube enters through the chalazal tissues. For example, Casuarina.
Hence In Casuarina, fertilization occurs by Chalazogamy.
  • So, the correct answer is 'Chalazogamy'.

Chalazogamy occurs in

botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

  1. Cucurbita

  2. Lily

  3. Populus

  4. Casuarina

Show answer
Correct Option: D
Explanation:
Chalazogamy is the entry of pollen tube in the ovule through chalazal tissue. It occurs in plants like Casuarina. In Cucurbita and Populus, pollen tube enters the ovule through the integuments and this is known as mesogamy. In Lily, pollen tube enters the ovule through the micropyle and this is known as porogamy.
So, the correct answer is A.

The phenomenon of pollen tube entering the ovule laterally through integuments is called

botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

  1. Mesogamy

  2. Aporogamy

  3. Chalazogamy

  4. Vegetative fertilization

Show answer
Correct Option: A
Explanation:
•Mesogamy is the entry of pollen tube through the integuments.
•Aporogamy is the condition in which pollen tube enters the ovule through a path other than micropyle.
•Chalazogamy is the entry of pollen tube through chalaza.
•Vegetative fertilisation is a part of double fertilisation in Angiosperms, in which one of the two male gametes fuses with the diploid secondary nucleus and this results in the formation of a triploid primary endosperm mother cell. It is also known as triple fusion.
So, the correct answer is A.

In Casuarina, fertilization takes place through

botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

  1. Mesogamy

  2. Porogamy

  3. Chalazogamy

  4. Apogamy

Show answer
Correct Option: C
Explanation:
• Mesogamy is the entry of pollen tube in the ovule through the integuments (e.g. Cucurbita) or through funiculus (e.g. Pistacia).
• Porogamy is the entry of pollen tube in the ovule through the micropyle. It occurs in most of the angiosperms.
• Chalazogamy is the entry of pollen tube in the ovule through the chalazal tissues. Example, Casuarina.
• Apogamy is a type of reproduction in which sporophyte develops directly from the gametophyte without the fusion of gametes.
Hence, in Casuarina fertilization takes place through Chalaza, as pollen tube enters the ovule from Chalaza to release the male gametes which will fuse with the egg cell and central cell, resulting in fertilization.
So, the correct answer is C.

In ovule, exostome is

botany modes of reproduction introduction to flower pre fertilization - plants sexual reproduction in flowering plants the origin of cells and cell division

  1. Area just outside the micropyle

  2. Area at the tip of nucellus

  3. Part of micropyle enclosed by inner integument

  4. Part of micropyle enclosed by outer integument

Show answer
Correct Option: D
Explanation:

In an ovule, an opening is formed at the tip of ovule by the integuments called as micropyle. The micropyle acts as a pore for the entry of pollen tube into the ovule for fertilization. In bitegmic ovules, the opening is formed by the inner integument and is called endostome. If the opening is formed by the outer integument it is called exostome. Sometimes it is formed by both the integuments, then it is called as amphistome. 

Thus, the correct answer is option D.