Explanation:
charles darwin proposed thoery of natural selection.he had collected imnumerable specimens of plant and animals.he published concept survival of fittest. while explaining he says that There is always competition for food.only those organism survive which shows adptations in various reasons. it thoery of natural selection.
There are some objections,
1. natural selection is not only factor responsible for evolution.
2. darwin did not mention uesful and useless modifications.
3. There is no explanation about slow and abrupt changes
Answer:
Somatic vs Germline Mutations. ... Somatic mutations – occur in a single body cell and cannot be inherited (only tissues derived from mutated cell are affected) Germline mutations – occur in gametes and can be passed onto offspring (every cell in the entire organism will be affected)
Explanation:
Answer:
1.Carbon is small and has four valence electrons; these factors combine into a unique structure that allows it to easily make a chain of carbon atoms. It creates covalent bonds — the strongest bonds between atoms. A covalent bond is one where atoms share electrons to form a bond.
2.But what makes carbon unique is that it can bond with other carbon atoms to create long carbon chains and rings. No other element is capable of forming molecules as large and complex as carbon based molecules (think about it—without carbon chains and rings, there could be no DNA!)
3.Because the carbon-carbon bond is stronger than the silicon-silicon bond, carbon compounds stay together in water while silicon compounds break apart. Besides this, another probable reason for the dominance of carbon-based molecules on Earth is the abundance of oxygen.
*Hope it helped*
Explanation:
