A) a common ancestor
Homologous structures are structures that are similar in related organisms. There is a basic pattern of bones which can be inherited from a common ancestor
<u>Answer:</u>
<em>There are innermost serious membranes that cover the heart is Parietal Pericardium.</em>
<u>Explanation:</u>
Heart is <em>covered by pericardium</em> in two sides, inner and outer sides. The inner membrane is parietal pericardium and the outer one is visceral pericardium. Pericardium is made up of <em>fiber tissues</em> that strongly protect the heart from all around.
The<em> main function of pericardium</em> is to protect the heart from any injuries and prevent the infections. The serious pericardium helps in<em> lubricating the heart. </em>
Most bacteria are heterotrophic decomposers, which means they depend on other organisms for food and feed on dead matter.
Answer:
Energy in an ecosystem is mainly made by the producers of an ecosystem. The net primary productivity in an ecosystem depends on many factors. Some of them are:
- Amount of sunlight: The amount of sunlight that the plants and trees might be has basic influence on the primary productivity. Plants and trees receiving enough sun light will be able to make more food for organisms living in that area as compared to the producers which do not receive enough sun light.
- Soil texture: The soil texture and the availability of nutrients heavily influence the primary productivity of an ecosystem. An area having a soil texture with not enough nutrients will not be able to grow more plants. As a result, the productivity would decrease.
