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.
Answer:
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First one, disease causing microorganisms
1. penicillin 2. lovastatin
Hope this helps don't forget to hit that heart :)
Klinglers iron agar medium is used to find the enterobacteria which can ferment glucose , lactose and hydrogen Sulphide . They are H₂S producing bacteria .
This media have phenol red as an indicator. When the glucose is fermented to acid , the production of acid turn the indicator from red to yellow, but it is then reoxidised and turns red again . When lactose is fermented it produce large amount of acid , and turn indicator yellow . Hence the slant will become yellow.And combination of ferrous sulphate and sodium thiosulphate helps in detection of H₂S which produce black color at the butt .
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