Natural selection! In the theory of natural selection, those with less beneficial traits won't live to reproduce, but those with beneficial traits will be able to reproduce and pass on those traits to their offspring, which significantly increases the frequency of those beneficial traits.
Carbon cycle refers to an array of procedures by which the compounds of carbon are interconverted in the environment, comprising the inclusion of carbon dioxide into living tissue by the process of photosynthesis and then getting back into the atmosphere via respiration, the burning of fossil fuels, and the decomposition of dead organisms.
The following are the steps that illustrate how the carbon cycle functions:
1. Carbon enters the atmosphere as carbon dioxide from combustion and respiration.
2. The absorption of carbon dioxide takes place by the producers to manufacture glucose in photosynthesis.
3. The animals feed on the plant passing the carbon components through the food chain. The majority of the consumed carbon is exhaled in the form of CO2, which was produced at the time of aerobic respiration. The plants and animals die eventually.
4. The dead plants and animals get dissociated by the dead organisms and return the carbon present in their bodies back to the atmosphere as CO2 by the process of respiration. In certain occasions, the dead plant and animals get converted into fossil fuel, which is available in future for combustion.
Convection drives the circulation of air in the earth's atmosphere.
One of the differences between the cell membrane and the cell wall is in the type of organisms that they are found in. A cell wall is found in plants only. A cell membrane is found in all organisms including plants. Present only in plants, and in some fungi, bacteria, algae.