Answer:
Survey
Explanation:
Because if you think about it carefully you really cant observe it. Your main goal is to compare them and with that we need a survey to get the data from both sides. Leaving us with the Survey
The more numbers of the homologous structure, the more likely they have recently shared a common ancestor.
Explanation:
Homologous organs are defined as those organs which do have different functions but a similar basic structure which denotes the divergent evolution. Homologous organs are seen in species that are very close to each other which are more related with each other in terms of evolution. For example, a bird is more close to each man than a fish, so do share more homologous organs common to man than fishes do. Examples of the homologous organs are hands of human and wings of birds. They have same basic structure like skeletal structure which is humerus, radius, ulna, carpals, metacarpals and phalanges. They are similar in structure but have different functions like flying in birds and gathering food in humans.
Answer:Valves stop blood flowing backwards
Explanation: Valve are flags of tissue that control the direction of the blood in our heart.,it prevent the backwards flow of blood. valves regulate blood from flowing back into the atria.The right and left atrio-ventricular valves prevent blood from flowing backwards into atria. When the ventricle is full,the valve prevent backwards flow of blood.
It suggest that any living abject has DNA. Even if the organ is not living it still consist of DNA because it doesn’t disappear after it dies