Evolution is the sequence of gradual changes which take place in primitive organisms over millions of years in which new species are produced.Since there is no actual progress in the concept of evolution, the two concepts should not be linked. Simply put, evolution is the process of producing a variety of life forms and modifying …
The gradual change from simple to complex life forms, or from ancient organisms that lived millions of years ago to contemporary species, is known as evolution. Simple life forms undergo changes, improvements, and modifications during evolution. The remains or impressions of species that existed in the distant past are known as fossils. The existence of …
When animals or plants die, their remains are decomposed by microorganisms in the presence of oxygen, moisture, etc. The absence of oxygen, moisture, and other environmental factors can sometimes prevent the body of an organism from completely decaying. When we dig the earth, we find an organism’s body (or a part of its body) preserved …
Those organs with the same basic structure and similar embryonic origin but different functions are called homologous organs. These organs follow the same basic plant of the organisation during development, but in adults got modified to perform different functions as an adaptation to different environments. Those organs which have a different basic structure and embryonic …
(a) Planaria, insects, octopuses and vertebrates cannot be grouped based on an eye. Eyes of insects, octopuses, Planaria and vertebrates are analogous organs which have developed over a generation as an adaptation for a similar function. They represent convergent evolution where distantly related groups develop similar functional structures as an adaptation for the same function. …
Introduction : Mendel (1856-1863) conducted hybridization experiments on garden peas( Pisum sativum). During that period, he chose some characteristics of the peas and conducted some cross-pollination on the pea lines that showed stable trait inheritance and underwent continuous self-pollination. The two experiments lead to the formulation of Mendel’s laws known as laws of inheritance which are: …
Introduction Mendel (1856-1863) conducted hybridization experiments on garden peas( Pisum sativum). During that period, he chose some characteristics of the peas and conducted some cross-pollination on the pea lines that showed stable trait inheritance and underwent continuous self-pollination. Why was Pea Plant Selected for Mendel’s Experiments? He selected a pea plant for his experiments for …
(a) Homologous organs perform different functions in different species, they share a common basic structure and embryonic origin. For example, the forelimbs of a frog, lizard, bird and human being show similarities in basic structure. Despite the fact that these organs serve very different functions, the basic similarity in the forelimbs of these various vertebrates …
Evolution is a sequence of gradual changes from simple to complex life forms. Many organs adapt to new functions as a result of evolution. Homologous organs are those that have a similar basic structure and embryonic origin but carry out different functions in various species. Divergent evolution leads to homologous structures. Homology suggests a common ancestry. Example, …
(a) (i) Broccoli and cabbage – Homologous organs(ii) Ginger and radish – Analogous organs(iii) Forelimbs of birds and lizards – Homologous organs(iv) Wings of a bat and wings of a bird – Analogous organs (b) Homologous organs have the same fundamental structure but different in function Analogous organs have different internal structures but similar functions.
