NEET BIOLOGY

Detailed explanation-1: -Homologous structures provide evidence for common ancestry, while analogous structures show that similar selective pressures can produce similar adaptations (beneficial features). Similarities and differences among biological molecules (e.g., in the DNA sequence of genes) can be used to determine species’ relatedness.

Detailed explanation-2: -The anatomical structures and physiological functions of different species provide evidence of evolution. Scientists compare and contrast types of anatomical features, known as homologous structures, vestigial structures, and analogous structures, to figure out how closely related different organisms are.

Detailed explanation-3: -Fossil Record Bones, teeth, shells, imprints, or even entirely preserved organisms can paint a picture of what life was in time periods from long ago. Not only does it give us clues to organisms that are long extinct, but it also can show intermediate forms of species as they underwent speciation.

Detailed explanation-4: -Homologous structures are similar physical features in organisms that share a common ancestor, but the features serve completely different functions. An example of homologous structures are the limbs of humans, cats, whales, and bats.

Detailed explanation-5: -Anatomy and Embryology Another type of evidence for evolution is the presence of structures in organisms that share the same basic form. For example, the bones in the appendages of a human, dog, bird, and whale all share the same overall construction (Figure 21.5.