Answer:
) a delay of the action potential at the atrioventricular node
Explanation:
The reason for the short delay of 0.9s. is to ensure maximum contractions of the atrial to eject blood into the relaxed ventricles.(ventricular filing).
Thus when the atrial is contracting,the ventricles relax and vice versa.The short duration for the artrial contraction to occur for blood ejection into the relax ventricles guarantee that artial systole can not overlap the ventricle systole.
The artial must contract first for the ventricle fillings,and when this is completed,the atrioventricular valves closes,and blood flow through the aorta to the systemic circulation from the left ventricle and into the pulmonary circulation through the pulmonary vein.
This occurs simultaneously with both the R and L Artrial,and right and left Ventricles.
Answer:
1) About 8.7 million.
2) They are being found everywhere.
Answer
:Photosynthesis can be explained in four simple steps, as follows.
Step 1:
The plant gathers sunlight from the chlorophyll in the cells to convert into energy.
Step 2:
The light energy then reactions and forms hydrogen and oxygen.
Step 3:
The hydrogen joins with carbon dioxide and create sugars.
Step 4:
The sugar is then separated, some to be used as the structure in the cell wall, and some stored in the ATP for later use.
Explanation:
Answer:
Fred Hoyle
Explanation:
Sir Fred Hoyle FRS was an English astronomer who formulated the theory of stellar nucleosynthesis. He also held controversial stances on other scientific matters—in particular his rejection of the "Big Bang" theory, a term coined by him on BBC radio, and his promotion of panspermia as the origin of life on Earth
Aorta!
Hope this helps! :)