Tag: botany

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Questions Related to botany

Multiple choice botany classical genetics variation and its type natural selection introduction to genetics

Mutations are responsible for.

  1. Extinction of organisms

  2. Variations in population

  3. Increase in population

  4. Maintaining genetic continuity
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Mutations are changes in the DNA. A single mutation can have a large effect, but in many cases, evolutionary change is based on the accumulation of many mutations. Gene flow is any movement of genes from one population to another and is an important source of genetic variation.

So, the correct answer is 'Variations in population'.
Multiple choice botany classical genetics variation and its type natural selection introduction to genetics

Recombinations and variations in eucaryotic organisms are due to

  1. Mitosis and meiosis

  2. Fertilization and mitosis

  3. Meiosis and fertilisation

  4. Meiosis and amitosis
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The process of forming new allelic combination in offspring by exchanges between genetic materials of parents is called Recombination.

Variation is a change or slight difference in condition, amount, or level, typically within certain limits appear in the progeny compared with parents.

Recombination and variations appear in sexually reproducing organisms during meiosis and fertilization.

So, the correct option is ‘Meiosis and fertilization’.

Multiple choice botany classical genetics variation and its type natural selection introduction to genetics

Some individuals produce lesser amounts of insulin. It is a type of

  1. Physiological variation

  2. Behavioural variation

  3. Morphological variation

  4. All the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • Physiological variation is related to the differences in the ways individuals of the same species react to conditions in their environment because of difference in their functioning of the body. Production of insulin is an example of physiological variation.
  • So, the correct option is 'Physiological variation'
Multiple choice botany classical genetics variation and its type natural selection introduction to genetics

Aspects such as sedentary habit, territoriality, etc., not aiding diversification are classified as 

  1. Reproductive isolation

  2. Mutational effects

  3. Biological barriers

  4. Genetic incompatibility
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Biological barriers are factors that prevent species migration, interbreeding, or free movement. What determines the barrier depends on the species and it's method of movement. For some species biological barriers are sedentary habits, physical like bodies of water, mountains, or deserts.
Mutation effects is the formation of altered protein from an altered or mutated genes.
When the species are not able to cross breed is called as genetic incompatibility
Thus, the correct answer is option C.
Multiple choice botany classical genetics variation and its type natural selection introduction to genetics

Which of the following statements is correct?

  1. Accumulation of useful mutations through ages has led to the creation of new species of living beings.

  2. Genetic variability provides raw material for the operation of natural selection and reproductive isolation.

  3. Genetic variability is produced by gene mutations.

  4. All of the above.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Genetic variability is the change in the sequence of the gens due to mutations. These mutations has led to new species generation. The so evolved species are selected in the environment based on natural selection

Multiple choice botany classical genetics variation and its type natural selection introduction to genetics

Laboratory mice are to be classified based on genes A, B, and C, none of  these are lethal genes. How many would be genetically different gametes if they are formed by genotype AaBbCc?

  1. $3$
  2. $6$
  3. $8$
  4. $9$
  5. $12$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

For a genotype AaBbCc, the number of different gametes produced is 2^n, where n is the number of heterozygous gene pairs. Here, n=3, so 2^3 = 8.

Multiple choice botany classical genetics variation and its type natural selection introduction to genetics

Ultimate source of variation is

  1. Fertilization

  2. Mitosis

  3. Meiosis

  4. Mutations
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Variation is a change or slight difference in condition, amount, or level, typically within certain limits appear in the progeny compared with parents. Variations appear in sexually reproducing organisms during meiosis and fertilization and also by mutations. So, the correct option is ‘Mutation’.

Multiple choice botany classical genetics variation and its type natural selection introduction to genetics

The ultimate source of continuous variations is 

  1. Natural selection

  2. Sexual reproduction

  3. Hormonal action

  4. Mutations
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Sexual reproduction involves gamete formation and fertilisation. During fertilisation, 1 gamete from each parent combines to form a zygote. Because of recombination and independent assortment in meiosis, each gamete contains a different set of DNA. This produces a unique combination of genes in the resulting zygote and ultimately within the organism.

As reproduction takes place continuously throughout the generation as well as these variations are inheritable, it is the ultimate source of continuous variations.
So, the correct option is 'Sexual reproduction.'