The main responsible for the delay among the atrial and
ventricular contractions is the action potential conduction velocity of the AV
node cells. If the atria and ventricles contract simultaneously, atria cannot
give any help in filling the ventricles, which is needed, especially in those
with stiff ventricles as in the elderly. Hence atria have to contract first and
then the ventricles.
Carbon dioxide
this is the answer
Answer:
For many centuries, smallpox devastated mankind. In modern times we do not have to worry about it thanks to the remarkable work of Edward Jenner and later developments from his endeavors. With the rapid pace of vaccine development in recent decades, the historic origins of immunization are often forgotten. Unfortunately, since the attack on the World Trade Center on September 11, 2001, the threat of biological warfare and bioterrorism has reemerged. Smallpox has been identified as a possible agent of bioterrorism (1). It seems prudent to review the history of a disease known to few people in the 21st century.
Edward Jenner is well known around the world for his innovative contribution to immunization and the ultimate eradication of smallpox (2). Jenner's work is widely regarded as the foundation of immunology—despite the fact that he was neither the first to suggest that infection with cowpox conferred specific immunity to smallpox nor the first to attempt cowpox inoculation for this purpose.
Explanation:
The answer is D. Transports fluids throughout the plant.:)<span>
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Answer:
The article is not reflecting current knowledge.
Explanation:
Rick Potts had explained some thing which has already been established and published several years back by various scientist, researchers, biologist, ecologists and geologist.
Re publishing something again will not bring laurel to Pott, instead his article would not be considered a suitable article for reference.
Also , if Pott would have published any thing that talks of a way ahead of those previous publication, even then his article could be referred.