True true true true true true
For giving you understanding ; we need Free O2 but Oxygen is also available in H20 right why dont we use it !!
As the early atmosphere was reducing as there was no free oxygen but it was later produced by chemoautotrophic bacteria !! Living thing release O2 in atmosphere thus making it oxidising in nature and then life evolves !!
A. To remove excess Heat from the body
The first heart chamber that the dye would enter is right atrium.
This will be followed by
left ventricle
right ventricle
left atrium
coronary valve
the autonomic (involuntary) nervous system controls the rate at which the heartbeats. sympathetic (fight or flight) signals speed up the heart’s rate while parasympathetic (rest and digest) signals slow it down. The part or parts of the heart that forms sympathetic and parasympathetic neurons form synapses is called cardiac plexus.
Cardiac plexus is a plexus of the nerves that are present at the base of the heart and is divided into superficial and deep part. The sympathetic and the parasympathetic nerves form synapses with heart in the form of cardiac plexus.
The sympathetic nerves are responsible for activating flight or fight mode while parasympathetic nerves are responsible for restoring the normal body state.
To learn more about sympathetic nerves here
brainly.com/question/7495218
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