Answer:
The condition of the Earth had to become favourable before it could support any form of life.
The formation of the different layers around the earth like the ozone layer was necessary before life could originate. Primitive species such as some prokaryotes were able to live in hydrothermal conditions during the initial times. With the passage of time, as the concentration of oxygen increased due to photosynthetic prokaryotes, situations became favourable for eukaryotic organisms to arise.
Answer:
"A model that shows global systems, the processes that operate within each system and the ways those systems and processes interact."
Explanation:
In the global system mainly four types of models interact or co-ordinate between each other. When we take an example of the ecosystem, these four models can be predation, parasitism and herbivore. Interaction takes place in such a way that one model gets the benefits while the other one gets affected. But when talk about mutualism, both of them gets benefited from the interaction. The basis of the global system property is firstly made by the species interaction.
Chemoreceptor is a specialized sensory receptor cell, which responds to a chemical substance and generates a biological signal.
The type of chemoreceptor responsible for our sense of smell is called olfactory receptor. It is also known as odorant receptor, these are found in a small patch of tissue high inside the nose. These cells directly connected to the brain.
The correct option is D. There are four different nitrogenous bases in DNA molecules; these bases are joined together by different forces including hydrogen bonds. In DNA molecules, there are two hydrogen bonds between adenine and thymine while there are three hydrogen bonds between cytosine and guanine. Thus, the hydrogen bonds between cytosine and guanine is the stronger.
Answer:
probably not organic, unhealthy