Answer:
The correct answer will be option-C
Explanation:
The rhythm of the heartbeat is controlled by the pacemaker of the heart called the sino-atrial node.
The SA node generates action potentials which trigger the contraction and relaxation of the atrium and ventricles. The membrane potential generation initiates by the depolarization of the cell membrane when the L type of Ca⁺² ions opens up and calcium ions enter the cell.
This depolarizes the cell until the potential threshold is reached which lies between the -40 and -30 mV.
Thus, Option-C is the correct answer.
Answer:
The pulmonary vein and the jugular vein.
Explanation:
The greatest difference between the pulmonary vein and the jugular vein is that pulmonary vein takes oxygenated blood from both lungs towards the left atrium of heart while jugular vein takes the deoxygenated blood from head back towards right atrium of heart through superior vena cava.
So, the main difference is oxygenated and deoxygenated blood in the above mentioned veins.
Answer:
The influenza virus has a negative sense RNA genome. In order to replicate, this means that the virus must first produce positive sense mRNA in order to produce necessary enzymes. Once the enzymes are translated, replication can take place. Positive sense cRNA is then made from the original negative sense RNA, using the enzymes. Negative sense RNA progeny are then made from the positive sense cRNA. The final viral progeny eventually bud from the host cell, ready to infect other cells.
Explanation:
Answer: The carbon that plants need for photosynthesis comes from carbon dioxide, or CO2 that's present in our atmosphere.
Explanation: Carbon dioxide is released into the air by organisms, such as animals that undergo cellular respiration. In other words, we breathe out CO2 as a waste product.
