I found a similar question. If the attached document is the same as your supposed question, then my answer are below.
AV valves open - atrial pressure is greater than ventricular pressure
AV valves closed - Ventricular pressure rises above atrial pressure
Semilunar valves closed - ventricular pressure is lower than arterial pressure
Semilunar valves open - pressure in the ventricles is greater than the pressure in the great arteries
Answer:
A system that uses the sun's energy without requiring mechanical devices (pumps or fans) to distribute the collected heat are called solar system while radiator system uses fuel to heat the water. in active solar heating system, the SUN's energy used to heat water.
The sympathetic nervous system releases hormones known as catecholamines which increase the heart rate.
<h3>What is a heart rate? </h3>
it is the number of contractions of the heart per minute.
<h3>What are catecholamines?</h3>
These are the neurotransmitters that have a catechol and a side chain that is an amine.
<h3>Which catecholamines are released by the sympathetic nervous system?</h3>
Epinephrine and norepinephrine are the catecholamines that are released by the sympathetic nervous system to increase the heart rate.
<h3>Where are these hormones released?</h3>
These hormones are released in the blood.
<h3>How does this hormone increase the heart rate?</h3>
- "These hormones are released at the neuromuscular junction of the cardiac nerves."
- "They shorten the repolarization period."
- This speeds up the rate of depolarization and contraction and thus the heart rate is increased.
To learn more about sympathetic nervous system, hormones and heart rate here,
brainly.com/question/1155838
#SPJ2
Simple: The bone fracture does not break the skin
Compound: when the bone punctures the skin
Incomplete: the bone does not break completely
Impact: The bone fracture impacts another bone
Comminuted: The bone breaks into 3 or more pieces