Tag: introduction to genetics

Questions Related to introduction to genetics

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

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

  1. Physiological variation

  2. Behavioural variation

  3. Morphological variation

  4. All the above

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Correct Option: A
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'


Mutation, selection and genetic drift are three important forces which are responsible for evolutionary changes

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

  1. True

  2. False

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Correct Option: A
Explanation:

Evolution is dependent on the natural selection , genetic drift , gene flow , mutation are the main factors responsible for evolution .

Hence the given statement is true

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

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

  1. Reproductive isolation

  2. Mutational effects

  3. Biological barriers

  4. Genetic incompatibility

Show answer
Correct Option: C
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.

Which one of the following traits of the parents cannot be inherited by their children?

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

  1. Cleft chin

  2. Snub nose

  3. Scarred eyebrow

  4. Brown eyes

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Correct Option: C
Explanation:

Scarred eyebrow is an acquired trait which is never passed on to the offspring because scarring does not change the genes of the reproductive cells of the parent.

Which of the following statements is correct?

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

  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.

Show answer
Correct Option: D
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

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?

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

  1. $3$

  2. $6$

  3. $8$

  4. $9$

  5. $12$

Show answer
Correct Option: C

Ultimate source of variation is

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

  1. Fertilization

  2. Mitosis

  3. Meiosis

  4. Mutations

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Correct Option: D
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’.

The ultimate source of continuous variations is 

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

  1. Natural selection

  2. Sexual reproduction

  3. Hormonal action

  4. Mutations

Show answer
Correct Option: B
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.'

Which variations are temporary and are not connected with last or next generation?

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

  1. Hereditary variations

  2. Environmental variations

  3. Discontinuous variations

  4. Continuous variations

Show answer
Correct Option: B
Explanation:

In the living organisms, variation due to environment, not transmitted from generation to generation. so these are temporary, where as variations due to mutations are transmitted from generation to generation, so they are permanent. 

So, the correct option is 'Environmental variations'.

In introgressive hybridization, one species is completely replaced by another in nature.

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

  1. True

  2. False

Show answer
Correct Option: A
Explanation:
he movement of a gene (gene flow) from one species into the gene pool of another by the repeated backcrossing of an interspecific hybrid with one of its parent species is called Introgressive hybridization.
So the given statement is true.