The answer is <span>They both suggest that snakes evolved from an ancestor with legs.
The second choice is not correct since we have no information about pythons and other snakes. We only have the relationship between geckos, snakes and legless eels. So, it is said that </span><span>snakes in general have more DNA sequences in common with four-legged geckos than they do with legless eels. This means that snakes are closer to geckos than the legless eels. We cannot conclude from this information which evolved from which, but we can say that </span><span>snakes evolved from an ancestor with legs.
In different case, if the snakes had more DNA sequence in common with legless eels, we would conclude that the snakes evolved from an ancestor without legs.</span>
The question is incomplete as it does not have the options which are:
- there was no sulfur compound added to the medium, that could be used as an electron donor.
- no oxygen was added to the medium so the organism died.
- there is some inhibitory chemical that is preventing the growth of the bacterium.
- you were using the wrong type of sunlight as the energy source for the bacterium.
Answer:
There was no sulfur compound added to the medium, that could be used as an electron donor.
Explanation:
In the given question, the bacteria which are found in the pond uses light energy to use carbon dioxide and form the glucose molecule. These bacteria are known as phototrophic bacteria.
The process of photosynthesis requires an electron donor and an electron acceptor to use molecule.
The organism when provided the light and carbon dioxide artificially in a culture, the bacteria were not able to grow. The reason for this could be accounted as that there was no electron donor found in the media like sulfur which could donate the electron during the chain reaction.
Thus, the selected option is correct.
Answer:
macrophages
Explanation:
Macrophages are a type of immune cells that function as phagocyte. They are produced by white cells called the monocytes. Upon ingestion of bacterial cells, cytotoxic compounds e.g cytokines are produced that digest the bacteria.
The macrophages are activated by the presence of microbes in the blood. They activate antigen T presenting cells to produce cytokines that further destroy the engulfed bacteria.
<span>endocrine system.............</span>
