I'm not sure if I will answer the question you asked, as I many have interpreted it incorrectly. In natural selection, there must be variance in the gene pool, the total frequency of alleles in a population. Now, one of the organisms may have a gene that somehow helps them survive from the selective force much better compared to the others. If this does happen, over time the gene pool will narrow down to become just the genes of that organism that survived better in the first place because the rest would be taken care of by the selective force. So, the alleles and trait come from the first organisms that had the advantage over the others of its species.
Hello!
They are called producers because they're able to produce their own food by the process of photosyntessis.
Answer:
Explanation:
Prokaryotic cells are very simple so they have:
circular chromosome
smaller than eukaryotic cells
lack nuclei
have cell walls
Answer: B) are excited by light that falls in the center of their receptive field.
Explanation:
There are two types of bipolar cells present in the retina which are differentiated on the way the centres of their receptive fields respond to light. The names of bipolar cells are ON-centre and OFF-centre.
If a light fall at the centre of the receptive field of a bipolar cell, it will experience an exciting effect on that cell, resulting in it being depolarized, it is an ON-center cell.
Hence, the correct option is B.
Answer:
D. Particle A orbits the nucleus, and Particle B is located in the nucleus
Explanation:
Here since both particles are of the same atom and particle A is much lighter we can infer that Particle A is electron because electrons are much lighter than protons which are Particle B in this case. Thus, particle A orbits nucleus as an electron does and particle B is in nucleus where protons are.
