Answer:
Your heart changes its rate depending on the activity, so that it can carry blood to your muscles, and therefore it needs to beat stronger if you are performing some exercise, or not so strong if you are sleeping, for example.
Explanation:
Your heart is continuously beating to keep blood circulating throughout your body.
So, here it is why your heart changes its rate: Its rate changes depending on your activity level; it is lower while you are asleep and at rest and higher while you exercise to supply your muscles with enough freshly oxygenated blood to keep the functioning at a high level.
And how: depending on your activity level, your heart has to pump enough blood to your muscles. Blood carries needed oxygen and other nutrients. Muscles need more blood sugar than any other tissue especially when working hard. To supply your muscles with oxygen your heart needs to beat faster, and this builds up your heart muscles.
Planting vegetation and installing drainage pipes will help reduce erosion.
Answer:
Explanation:
Electricity is a flow of tiny particles called electrons which can travel through wires. This flow is often called an 'electric current'. Just like water, which can only flow down a hill, an electric current can only flow if there's something to give it a 'push'.
sorry if im incorrect
A- valve replacement
b- stents
x- heart transplant