The answer is external stimulus
<span>A(n)PRIMITIVE CHARACTER is one present in the common ancestor and all members of the group
Primitive character is also known as ancestral character in phylogenetics. It is defined as a characteristic that has undergone little change since time immemorial and is inherited from a common ancestor of a clad.
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Several things; don't use multiple patches, never take an ED medication (Erectile Dysfunction), if sign and symptoms including those of hypotensive reading, go to the emergency room.
When a cell needs energy it gets from the food that we eat and works like as usual.
The serous fluid within the pericardial cavity works to lubricate the membranes of the serous pericardium. It is the space between the layers of the pericardium.
<h3>What is the pericardial cavity?</h3>
The pericardial cavity refers to the space between different layers of the pericardium in the heart.
The pericardium is one of the three tissues that form the heart (i.e., pericardium, myocardium, and endocardium).
The pericardial cavity is composed of a serous fluid capable of reducing surface tension and lubricating this layer.
Learn more about the pericardial cavity here:
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