Hormones derived from amino acids can cause different effects in different cells depending on the type of cell and its signal transduction pathway.
An arrangement of chemical reactions in a cell that happens when a particle, for example, a hormone, joins to a receptor on the cell layer. The pathway is really a course of biochemical responses inside the cell that eventually achieve the objective particle or response.
Answer:
There are many types of evidence which support the theory of evolution such as comparative anatomy, fossil records, phylogenetic relationship, embryology et cetera
Comparative anatomy includes homologous organs and analogous organs. They support divergent and convergent evolution respectively.
For example, the homologous structure of limb of humans, birds, bat, horse, whale et cetera show that they are made up of the same set of bones which are humerus, radius, ulna, carpals, metacarpals, and phalanges.
It shows divergent evolution and supports that these organisms have evolved from a common ancestor.
Embryological evidence: When early stages of embryological development of different organisms are compared, it is found that these stages are similar at different levels of development.
For example:
- The appearance of pharyngeal-arch (gill-like structures) in vertebrates during embryo development.
- Salamanders and terrestrial frogs pass through larval stages within an egg. They possess the features similar to aquatic larvae, however, when they hatched out the eggs being ready for life on land.
