Heredity and Evolution Test - 22

Mendel picked pea plants for his experiment. The reasons for the selection of pea plants for the genetic experiments are: 
1) Easy to grow in the garden.
2) Pea plants can be self-fertilized (easy to obtain pure breed plants).
3) The generation time of pea plants is less. 
4) Pea plants have easily identifiable traits.
Thus, the correct answer is option D.

• The evolutionary process by which new biological species arise is called speciation. 
• Speciation can be driven by evolution, which is a process that results in the accumulation of many small genetic changes called mutations in a population over a long period of time.
  
• It is an irreversible process. 

So, the correct answer is option B. 

• The evolution has lead several morphological and genetic changes in the organism which leads to better adaptation. 
• Chimpanzees make tools and use them to acquire foods and for social displays. 
• They have sophisticated hunting strategies requiring cooperation, influence and rank, they are status conscious, manipulative and capable of deception. 
• They can also learn to use symbols and understand aspects of human language and are capable of spontaneous planning for a future state or event. 
• So, they are most intelligent apes compared to gibbon, orangutan and gorilla.
• Thus, the correct answer is option D.

• Fossils provide direct evidence of evolution. 
• Fossils are body remains of dead plants and animals or their impressions preserved in layers of the Earth and rocks. 
• The fossil position in the layer of earth relates to the time of extinction of organisms, If the fossil of an organism is found in the deeper layers of earth, then it is predicted that extinction of organisms has occurred thousands of years ago.

A trait is a distinguishing quality or characteristic of an organism. For example, eye color is a character or abstraction of an attribute, while blue, brown, and hazel are traits.

Solution

Correct answer is option B.

Explanation for correct option:

• Fertilization is the process of fusion of nuclei of two haploid reproductive cells, sperm (n) and egg or oocyte (n) to produce a diploid zygote (2n).
• Sperm and egg carries the genes from father and mother respectively. Since unitedly they form a zygote, it has genes from both the parents equally. 

T represents the tall condition and t represents the dwarf condition. R represents red and r represents white. Thus, condition Tt is hybrid tall whereas Rr is hybrid red thus, the true hybrid condition is TtRr.

Gregor Mendel chose the pea plants for his experiments because the garden pea is an ideal subject in the study of genetics for the following reasons :

• Presence of observable traits with contrasting characters
• Produces many offspring in one cross
• Short life cycle
• Ease in manipulating pollination (cross pollination)
  

CORRECT ANSWER-D