Well I do know the answer to question #5 is temperature
Answer:
The correct answer will be option A.
Explanation:
The electrical impulses are generated in the sino-atrial node or SA node, a mass of cells which generates impulse in the upper atrium.
This electrical impulse transmits from the sino-atrial node to the atrio-ventricular node in the lower portion of the upper atrium through the internodal pathway- the pathway composed of atrial cells.
Once the impulse reaches the AV node, it is transferred to the ventricular portion of the heart through Bundle of His presence in the ventricular septum. This bundle of his divides into left and right ventricles through bundle branches and stimulates both the ventricles.
Thus, option-A is the correct answer.
The hypothesis that all modern humans descended from an African lineage is supported by the mitochondrial DNA evidence. The Eve hypothesis is the hypothesis that is based on the study of mirtochodrial DNA; that modern humans have a common female ancestor who lived in Africa around 200,000 years ago. It is also called African Eve hypothesis.
Answer:
An oil spill, fertilizer run off, and another thing i could think of is a flood hope this helped :)
Explanation: