Which of these are homologous structures?
A dolphin’s flipper, a bird’s wing, a cat’s leg, and a human arm are considered homologous structures. Bats, whales, and many other animals have very similar homologous structures, demonstrating that these creatures all had a common ancestor.
What is an example of analogous structures?
Analogous structures are structures that are similar in unrelated organisms. The structures are similar because they evolved to do the same job, not because they were inherited from a common ancestor. For example, the wings of bats and birds, shown in Figure below, look similar on the outside.
Are eyes analogous structures?
Of our five organisms, only the vertebrates (represented by sharks and mice) inherited their eye structures from a common ancestor. In the other three cases, eyes evolved independently and are analogous. Eyes have evolved independently a number of times and are amazingly diverse in form and function.
What is an analogous trait?
In morphology, analogous traits arise when different species live in similar ways and/or a similar environment, and so face the same environmental factors. When occupying similar ecological niches (that is, a distinctive way of life) similar problems can lead to similar solutions.
Why are wings analogous?
Bird and bat wings are analogous — that is, they have separate evolutionary origins, but are superficially similar because they have both experienced natural selection that shaped them to play a key role in flight. Analogies are the result of convergent evolution.
What are homologous organs give examples?
Homologous organs: These are organs having a similar structural plan, but different functions. For example, the wing of a bat, the flipper of a seal, the front leg of a horse and the arm of a man perform different functions, but have the same structural plan.
What the difference between homologous and heterologous?
When chromosomes are homologous, it means that they are the same, at least in terms of the gene sequences and loci. Heterologous, in essence, means “different”. Homologous chromosomes have alleles on the same genes located in the same loci. Heterologous chromosomes have alleles on different genes.
What is heterologous structure?
Definition. adjective. (1) Of, or relating to, tissues or cytologic elements not normally found parts of the body of an individual, or that are derived from a different species. (2) Not corresponding in structure or evolutionary origin.