Acquired and Inherited Traits - Definition, Differences, Examples

To ensure the survival of one species, it is very much necessary to have a reproduction process. In the reproduction process, there are two types of reproduction, namely asexual and sexual reproduction. Some amount of variation can be observed in the new ones. In asexual reproduction, these variations are a little less but in sexual reproduction, these variations are more. Since sexual reproduction involves two parents, meaning two gametes from each individual, the new DNA formed will have a new sequence which results in some variations. These variant characters are classified into inherited and acquired characters.

Acquired and Inherited Traits

The variations occur in sexual reproduction or due to some minor errors in DNA copying. Let us consider that under a shade of bushes there live some 12 beetles. Due to some variations, one of the Beatles is green, and the other Beatles are red. Also considered that these Beatles will produce sexually, leading to variations. Consider that crows will eat these Beatles. The green-colored battles are camouflaged by the bushes due to the green color of the bushes. The red-colored ones are easily identified by crows and are eaten. In this course of process, the red-colored Beatles will extinct eventually. Latest imaging another situation where in the green colored species of Beatles are produced as a result of variance and are living with the red colored Beatles. Imagine an elephant group passes nearby and the elephant's foot accidentally falls on the group of red beetles and all the red beetles died. As the beetle population increases again, most Beatles found are green colored ones. Let us consider another scenario where due to some drought situation all the Beatles living under the shade of that bushes how become so weak and thin that this situation continues for a few generations. If the drought conditions are sensed and if it starts raining once again if the bushes grow properly which are the food sources for the Beatles, then the Beatles will grow stronger and fitter than they were before drought conditions.

In the first case scenario, the color change gave an additional advantage of survival. This was a naturally selected variant. The green beetle population growth due to the evolution which is directed by natural selection.  

But in the second scenario, there was no survival advantage due to the new variant. It was an accidental incident which led to the extension of red-colored beetles. So, in smaller populations, it is more common than changes occurring due to DNA being more frequent.

In the third scenario, we have seen that the shape of the body is restored when they get enough food like earlier. This can't be called a variation.

Theory of natural selection

Charles Robert Darwin (1809-1882) is the first scientist who brought the thought of acquired and inherited traits for the first time. When he was 22 years old, he went on a voyage for 5 years to South America, the Islands of South America and its coast. During his voyage, he conducted tests on a variety of life on earth. He continued these tests even after returning to England. He conducted several experiments before producing his own hypothesis that evolution occurs due to natural selection. Furthermore, he did not know how variations occurred in species.

Acquired traits

In sexually reproducing organisms, there is a specialized reproductive tissue called as germ cells. The changes occurred in the DNA of germ cells can only be transferred to the next generations. In the third scenario, we have seen earlier that low weight is not a character that is going to be inherited. Even if the Beatles will have low weight for few generations due to scarcity of food, the stronger beetles will be found once the drought conditions are over. What about changes occurring to our body cells other than self or not going to be transferred to the next generation.  

Latest try to understand this concept with another good example. Let us breed a few mice for our experimental purpose. Let us cut the tails of these mice for a few generations. Even if we continue this process for up to 50 generations or more, the character of mice giving birth to younger mine with tails is not going to change as the changes are not made in the joint cells by cutting the tails of mice.

Thus, we can state that acquired characters are not transferred to the next generations.

Inherited traits

Acquired traits are the characteristics which are transferred from parent generations to the next generation. Acquired characters include hair color, body complexion, eye color etc. These characters are transferred through DNA. Due to some crossover or sexual reproduction if any of the character gets altered this will be stored in the DNA of germ cells which will be transferred to next generation and this character will be expressed in the upcoming generations.

Inheritance of characters from parents is equally contributed by both males and females. Expression of these characters depends on the genes we get. Gregor Johann Mendel (1822-1884) has given a greater contribution by his experiments on garden peas. He chooses garden peas for the hair experiment because he could find seven characters with alternative expressions.  

Let us take the parent generation of a garden pea for our experiment. Let us consider the character height. The height has two alternatives, namely tall and short. If we cross-breed these two parent generations in the first F1 generation, we won't get short character expressed at all. This is because in the F1 generation we get genes of both tall and short height, but the short character is suppressed and the dominant character of tall is expressed. If we cross-breed these F1 generation peas and if we observe the characters in the F2 generation, we can observe the short characters' environment. This is because the characters we acquire are expressed.

Choosing Parent generation for reproduction which will have TT genes for tall and tt genes for short height character.

Choosing F1 generation for reproduction. F1 generation will have genes Tt for height Character.

Thus, the short character is expressed in 25% of the Plants in F2 generation.

Difference between Acquired and Inherited traits

Conceptual Question 

Question 1: What are acquired characters?

Answer :

The characteristics are expressed due to some change in the environment or some accident that are present only in the generations which are acquired during their life. These characters are not going to transfer to the next generation as these changes are not recorded in the DNA sequence.

Question 2: What are inherited characters?

Answer :

The characteristics that the younger generations get from the parent generations through genes are called inherited characters. These characters will be passed on to upcoming generations if there is no change due to variation. This character or stored in the form of information in the DNA sequence of germ cells.

Question 3: What is natural selection?

Answer :

Due to some changes in the environment, accidents or some variations sum of the organisms of species of a population cannot survive and are going extinct eventually. This process is called natural selection.

Question 4: What is the reason for not a transfer of characters that are acquired during life?

Answer :

The acquired characters are present to the existing generation only. The changes occurring in the body of living organisms are not going to store in the DNA of germ cells. Only the changes present or made in the DNA offer germ cells are going to pass to the next generation.

Question 5: Why In the F1 generation of garden peas in the experiment conducted by Mendel did the character short not expressed?

Answer :

In the F1 generation even if both the genes present were carrying the character of both tall and short height the short character did not appear because in the garden peas the height character tall is the dominant character and can easily suppress the short height character. Due to the dominance of the tall height character the short height character is suppressed and is not expressed in the F1 generation.

Question 6: Explain with an example of natural selection.

Answer :

Let us consider that under a shade of bushes there live some 12 beetles. Due to some variations, one of the Beatles is green in color and the other Beatles are red in color. Also considered that these Beatles will produce sexually leading to variations. Consider that crows will eat these Beatles. The green-colored battles are camouflaged by the bushes due to the green color of the bushes. The red-colored ones are easily identified by crows and are eaten. In this course of process, the red-colored Beatles will extinct eventually.