Tag: botany

Questions Related to botany

In a woody dicotyledonous tree, which of the following parts will mainly consist of primary tissues -

botany plant tissues introduction to tissue tissues - "the teams of workers" introduction to tissues

  1. Stem and root

  2. All parts

  3. Shoot tips and root tips

  4. Flowers, fruit and leaves

Show answer
Correct Option: C
Explanation:
In a woody dicotyledonous tree, the meristems which occur at tips of roots and shoots produce primary tissues and are called apical meristems.
So, the correct answer is 'Shoot tips and Root tips'.

State whether the following statements are true or false.
An extracellular matrix helps some cells to adhere to neighbouring cells.

botany plant tissues introduction to tissue tissues - "the teams of workers" introduction to tissues

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

Extracellular matrix is the network of macromolecules like collagen, enzymes etc, which provide structural support to the cells. They help in the formation of tissues and organs. Extracellular matrix functions as cell adhesive as they are helpful in the interaction between cells and matrix.

So, the correct statement is 'True'.

The systems in an organism work independently.

botany plant tissues introduction to tissue tissues - "the teams of workers" introduction to tissues

  1. True

  2. False

Show answer
Correct Option: B
Explanation:
Systems present in your body are the circulatory, respiratory, muscular, digestive, integumentary, endocrine, reproductive, and nervous systems. All of these systems have specific functions but they cannot function independently, meaning that they rely on all the other systems in order to work properly.

So, the correct answer is 'False'.

We do not sense any pain when we clip our nails or cut our hair. Why?

botany plant tissues introduction to tissue tissues - "the teams of workers" introduction to tissues

  1. They are made up of dead cells.

  2. These parts are senseless.

  3. They are very strong to tolerate pain.

  4. None of these.

Show answer
Correct Option: A
Explanation:
  • Hairs and nails are made of dead tissues. Only the base of the hair and the base of the nail are living. 
  • The dead tissues are devoid of the nerve supply which acts as messengers to convey the sensation of pain and in their absence, it cannot be perceived by our brain. 

  • Thus, the correct answer is option A.

Life cycle of Saccharomyces cerevisiae is 

botany modes of reproduction alternation of generation in angiosperms alternation of generation angiosperms

  1. Haplontic

  2. Diplontic

  3. Haplodiplontic

  4. None of the above

Show answer
Correct Option: C
Explanation:

Three types of life cycle patterns are seen in the Saccharomyces (yeasts).

(i)         Haplobiontic life cycle (Saccharomyces octopus)

(ii)        Diplobiontic life cycle (Saccharomyces ludwigii)

(iii)       Haplodiplontic life cycle (Saccharomyces cerevisiae)

The correct option is C.

Comparable to angiosperms which of the following alga exhibits diplontic life cycle?

botany modes of reproduction alternation of generation in angiosperms alternation of generation angiosperms

  1. Spirogyra

  2. Ectocarpus

  3. Fucus

  4. Polysiphonia

Show answer
Correct Option: C
Explanation:

  • Fucus (rockweed) is a type of brown alga and it displays the diploid life history. 
  • The zygote becomes the embryo and develops into the mature Fucus. 
  • The receptacles are reproductive branches and so contain many cavities with external pores. These pores contain antheridia (male) and oogonia (female)
  • The correct option is C.

Which one of the following shows the last diploid stage in the life cycle of angiosperms?

botany modes of reproduction alternation of generation in angiosperms alternation of generation angiosperms

  1. Microspore mother cell

  2. Zygote

  3. Nucellus

  4. Pollen grain

Show answer
Correct Option: A
Explanation:
A. Microspore mother cell or MMC is the diploid germ cell which forms microspores (pollen) by the process of microsporogenesis.
B. Zygote is the diploid structure formed by the fusion of male and female gametes.
C. Nucellus is the central part of ovule in which embryo is present. It is triploid.
D. Pollen grain or microspore is the haploid male gamete.
In the life cycle of angiosperms, zygote gives rise to a complete plant. The plant has germ cells which are diploid and produce gametes. The gametes then fuse to form a zygote. Hence, microspore mother cell is the last diploid stage because after that, haploid gametes are formed.
So, the correct answer is 'Microspore mother cell'.

Which of the statements regarding haplontic life cycle is incorrect?

botany modes of reproduction alternation of generation in angiosperms alternation of generation angiosperms

  1. Sporophytic generation is represented only by the one-celled zygote.

  2. There is no free-living sporophyte.

  3. Mitosis in the zygote results in the formation of haploid spores.

  4. The haploid spores divide mitotically and form the gametophyte.

Show answer
Correct Option: C
Explanation:

In a haplontic life cycle, the plant body is a gametophyte and dominant a dominant phase. The reproductive cell undergo mitosis to form gametes that are haploid, the gametic fusion results in a diploid zygote, which undergoes meiosis to form haploid spores.

So, the correct answer is 'Mitosis in the zygote results in the formation of haploid spores.'

Which one of the following has haplontic life cycle ?

botany modes of reproduction alternation of generation in angiosperms alternation of generation angiosperms

  1. Wheat

  2. Funaria

  3. Polytrichum

  4. Ustilago

Show answer
Correct Option: D
Explanation:

Ustilago is a genus of around 200 smut fungi parasitic on the grasses. In the haplontic life cycle, the haploid stage is multicellular whereas the diploid stage is a single cellular. The zygote undergoes meiosis to form the haploid spores. Each spore germinates are being divided to form gametophyte. The other three are not having this life cycle.

So, the correct answer is option D.

Haplo-diplontic life cycle is observed in how many of the following plants.
Pinus, Sphagnum, Polytrichum, Polysiphonia, Dryopteris, Riccia, Marchantis, Pteris, Selaginella, Ectocarpous, Volvox.

botany modes of reproduction alternation of generation in angiosperms alternation of generation angiosperms

  1. $6$

  2. $7$

  3. $8$

  4. $9$

Show answer
Correct Option: C
Explanation:

Haplo-Diplontic life cycle observed in 8 in following plants. This life cycle present only in Bryophytes and pteridophytes. So, sphagum, polytrichum, marchantis and riccia belongs to Bryophyta and selaginella, pteris, dryopteris and polysiphonia belongs to pteridophyta. That's why they consists Haplo-Diplontic life cylcle.