Pectinate muscles are parallel ridges in the walls of the atria of the heart. The name is due to their resemblance to the teeth of a comb (pecten). The heart is the organ pumps blood to all parts of the body. It is made up of four chambers, that is, right and left ventricles, left and right atria, and the blood vessels, Pulmonary artery, pulmonary vein, aorta, and venacava. An auricles are pouch like structure that increase the total filling capacity of the atrium and also increase the volume of blood that an atrium is able to contain.
Answer:
<em>The correct option is D) immigration</em>
Explanation:
Immigration can be described as the movement of an organism to another place for living. As the scenario in the question tells, the population of the endangered Philippine eagle could be seen only in one place hence we can say that the immigration rate of these organisms was zero because they could not be seen in any other place.
Other option, like option B, cannot be correct because mortality refers to the death rate and obviously many organisms of the species died due to which it became endangered.
