Tag: botany

Questions Related to botany

By which chromosomes are made of?

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. DNA and RNA

  2. DNA and proteins

  3. DNA only

  4. Proteins only

Show answer
Correct Option: B
Explanation:
  • Chromosomes are thread-like structures located inside the nucleus of animal and plant cells.
  •  Each chromosome is made of protein and a single molecule of deoxyribonucleic acid (DNA). Passed from parents to offspring, DNA contains the specific instructions that make each type of living creature unique.

Chromosomes contain information for inheritance of features from parents to next generation in the form of 

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. DNA

  2. RNA

  3. Proteins

  4. Chromatin

Show answer
Correct Option: A
Explanation:

Chromosomes are composed of DNA and proteins. DNA molecules contain the information necessary for constructing and organizing the cells. Functional segments of DNA are called as genes. In a cell, which is not dividing, this DNA is present as part of a chromatin material. Whenever the cell is about to divide, the chromatin material gets organized into chromosomes and transferred  to the next generation.

So, the correct answer is option A.

Chromosome carry .......... which helps in the inheritance or transfer of characters from the parents to the offspring.

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. Genes

  2. Enzymes

  3. RNA

  4. None of the above

Show answer
Correct Option: A
Explanation:

The nucleus of a cell contains chromosomes, which carry genetic information in a long molecule called as DNA. Genes are regions of DNA that carry the code to control a particular cell activity or the production of a particular protein.

So, the correct answer is option A.

The sex chromosomes of plants were first discovered in

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. Algae

  2. Fungi

  3. Pteridophyta

  4. Flowering plants

Show answer
Correct Option: D
Explanation:

Sex determination method is well understood in animals but not in plants. Plants may be monoecious or dioecious but the mechanism of sex differentiation was not well understood. It now appears that at least higher or flowering plants may be having sex determination mechanism based on sex chromosomes like animals, as humans which have XX and XY system of sex determination.

So, the correct answer is option D.

Eukaryotic chromosomes always exist

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. In pairs

  2. In association with mitochondria

  3. Singly

  4. None of the above

Show answer
Correct Option: D
Explanation:

Let's take Human somatic cell as an example for the typical eukaryotic cell.

The Human somatic cell is diploid that means the chromosomes exists in double number. 
And these chromosomes in the eukaryotic cell are located in the nucleus and no where associated with mitochondria.
The human somatic cell has 23 pairs of chromosomes but there are 24 types of chromosomes because X and Y chromosomes which are called as sex chromosomes were structurally not similar. 
The remaining 22 types of chromosomes exists in pairs which are homologous (structurally relative) with their pairs.
Hence, all the chromosomes doesn't exist in pairs.
And during the cell division process the homologous chromosomes were separated to opposite poles and therefore doesn't always exists in pairs.
And they also don't exist always in single.

The structure present over chromosome

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. Nucleolus

  2. Centromere

  3. Centrochrome

  4. Golgi bodies

Show answer
Correct Option: B
Explanation:

Centromere is a region of chromosomes which holds sister chromatids together and the area where chromosome are attached to spindle fibres during cell division.

In man the normal number of

chromosomes is

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. 42

  2. 44

  3. 46

  4. 48

Show answer
Correct Option: C
Explanation:

At first time Tizo and Levan in 1956 enabled the human geneticists to as certain the correct chromosome number (46 pairs).

Chromatid is

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. One half of chromosome

  2. Haploid chromosome

  3. Complete chromosome

  4. Duplicate chromosome

Show answer
Correct Option: A
Explanation:
1) A chromatid is one-half of two identical copies of a replicated chromosome. During cell division, the identical copies are joined together at centromere. Joined chromatids are known as sister chromatids. Once the joined sister chromatids separate from one another in anaphase of mitosis, each is known as a daughter chromosome.

2) In gamete cells, the cell contains half the number of chromosomes as body cells, are called Haploid chromosomes.

3) Body cells such as muscle,skinblood etc. These cells contains a complete set of chromosomes (46 in humans),are called Diploid or complete chromosomes.

So, the correct answer is 'One half of chromosome'.

The nuclear component that contains genes which are responsible for heredity or transfer of characteristics from parents to children is/are

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. the Chromosomes

  2. the Cytoplasm

  3. the Nucleolus

  4. All of the above

Show answer
Correct Option: A
Explanation:

The chromosomes are thread-like structures which can be seen enclosed in a cell nucleus. These chromosomes contain genes which are responsible for the transfer of characteristics from parents to the children.

Choose the correct statement.

botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

  1. Genes are located in the chromosomes

  2. Cell is locked in the nucleus

  3. Chromosomes are located in the nucleolus

  4. Cell membrane surrounds the nucleus

Show answer
Correct Option: A
Explanation:

The chromosomes are the condensed chromatin. They are made up of DNA and proteins Those sequences of DNA that code for proteins are called the genes. 

A. Genes are the segment of DNA that is located in the chromosome. The location of a gene on a chromosome is called the locus.
B. Nucleus is an organelle present inside the cell.
C. Nucleolus is the region on chromosomes that forms the ribosomal RNA.
D. Nuclear membrane surrounds the nucleus. Cell membrane surrounds the cell.
Hence, the correct answer is 'Genes are located in the chromosomes'