Answer;
-Atrial contraction;
Explanation:
-The cardiac cycle comprises all of the physiological events associated with a single heartbeat, including electrical events, mechanical events (pressures and volumes), and heart sounds.The atria and ventricles alternately contract in each cardiac cycle. The pressures in the chambers change greatly over the course of the cardiac cycle.
-During atrial contraction, blood flows from atria (high pressure) to ventricles (low pressure). Similarly, this same pressure gradient exists during ventricular filling.
Answer:Estuaries
Explanation:
Estuaries are areas where freshwater streams or rivers merge with the ocean. This mixing of waters with such different salt concentrations creates a very interesting and unique ecosystem
Answer:
I'm not sure I could say the sun because that's where the grass gets its energy but some people also would just say the grass but it's down to those two
Answer:
Variables are given a special name that only applies to experimental investigations. One is called the dependent variable and the other the independent variable. The independent variable is the variable the experimenter manipulates or changes, and is assumed to have a direct effect on the dependent variable.
___________________________________
<h3>Please mark me as Brainlist</h3>
That is true because that’s where it’s mostly are
