Tag: botany

Questions Related to botany

The number of chromatids, in a chromosome at anaphase is

  1. 2 in mitosis and 1 in meiosis

  2. 1 in mitosis and 2 in meiosis

  3. 2 each in mitosis and meiosis

  4. 2 in mitosis and 4 in meiosis


Correct Option: B
Explanation:

Meiosis occurs in two stages meiosis I and meiosis II. During meiosis I, homologous chromosomes separate and the number of chromosomes in daughter cells get reduced to half. This division is known as reductional division. During meiosis II, centromere splits and the chromosome number remains the same in the daughter cells. Hence, meiosis II is known as equational division. Hence, the number of chromatids in a chromosome at anaphase is 1 in mitosis and 2 in meiosis.

So, the correct answer is option B.

Identify the wrong statement about meiosis.

  1. Pairing of homologous chromosomes

  2. Four haploid cells are formed

  3. At the end of meiosis number of chromosomes are reduced to half

  4. Two cycle of DNA replication occur


Correct Option: D
Explanation:

Meiosis is a specialized type of cell division that reduces the chromosome number by half, creating four haploid cells. In meiosis, DNA replication is followed by two rounds of cell division to produce four daughter cells, each with half the number of chromosomes as the original parent cell. The two meiotic divisions are known as Meiosis I and Meiosis II.

So, the correct option is 'two cycles of DNA replication occur'.

Which of the following statement is not true for meiosis?

  1. It is a process in which the chromosomes duplicate only once

  2. It is a process in which the cell divides twice

  3. The karyokinesis skips one of the phases compared to mitosis

  4. It results in the formation of four haploid cells


Correct Option: C
Explanation:

The stage of karyokinesis does not skip any phase in mitosis as compared to meiosis because the cell division phases are the same in meiosis and mitosis.

So, the correct option is 'The karyokinesis skips one of the phases compared to mitosis'.

........... is used for preparing standard solutions in which it is always desired to maintain a constant pH.

  1. Buffer

  2. Plasma

  3. Serum

  4. None of the above


Correct Option: A
Explanation:

A buffer is a solution that resists a change in pH upon the addition of acidic or basic components. To effectively maintain a pH range, a buffer consists of a weak conjugate acid-base pair. It is either a weak acid and its conjugate base, or a weak base and its conjugate acid. Thus the correct answer is option A.

A buffer is a mixture of 

  1. Weak acid and its salt with a strong base

  2. Strong acid and its salt with a strong base

  3. Weak acid and its salt with a weak base

  4. None of the above


Correct Option: A
Explanation:
A buffer is a solution that resists a change in pH upon the addition of acidic or basic components. To effectively maintain a pH range, a buffer consists of a weak conjugate acid-base pair, meaning either a weak acid and its conjugate base, or a weak base and its conjugate acid. An acidic buffer solution is the one which has a pH less than 7. Acidic buffer solutions are commonly made from a weak acid and one of its salts having a strong base. Thus the correct answer is option A.

The proton-pumps provide energy to cells through.

  1. pH gradient and electro potential gradient

  2. ATP and ADP

  3. Auxins and hormones

  4. Carbolwdrates and lipids


Correct Option: A

If the activity of an enzyme is constant over a broad range of pH values,it is likely that

  1. only ionizing groups on the enzyme participate in the reaction

  2. only ionizing groups on the substrate participate in the reaction

  3. ionizing groups on the enzyme and substrate participate in the reaction

  4. the temperature should be changed in order to observe a pH effect


Correct Option: A
Explanation:
Changes in pH may influence the state of a catalyst as well as change the shape or charge properties of the substrate so that either the substrate can not tie to the dynamic site or it can't experience catalysis. In general, protein has a pH ideal. Anyway, the ideal isn't the equivalent for every chemical. 
So, the correct option is 'only ionizing groups on the enzyme participate in the reaction'

Find the wrong statement in the following.

  1. Animal fibres are proteins

  2. Plant fibres are fats

  3. Rearing of silk worms is called Sericulture

  4. Separation of silk fibre from cocoon is called Reeling


Correct Option: B
Explanation:

All statements are truly given below

1) Animal fibers consist largely of particular proteins.
2) Rearing of silkworms is called Sericulture.

3) Separation of silk fiber from the cocoon is called Reeling.
So, the correct option is 'Plant fibers are fats'.


Small plants which live for one or two seasons are

  1. Herbs

  2. Shrubs

  3. Trees

  4. Algae


Correct Option: A

A plant has weak stem which can coil around an upright support. It is a

  1. Liane

  2. Twiner

  3. Climber

  4. Creeper


Correct Option: B
Explanation:
A plant with a weak stem which can coil around an upright support is a twiner because as the name implies the weak stem twines or coils around the support for its growth.
So the correct option is Twiner.