Cellular injury is important because it can lead to diseases by interrupting how cells normally work. This can cause damage to tissues in our body. Several different things can cause cellular injury, including:

• Ischemia: This means there isn't enough blood reaching a part of the body. Without blood, cells don’t get enough oxygen, which can lead to cell death. An example of this is during heart attacks.

• Toxins: These are harmful substances. When our bodies come into contact with things like heavy metals, it can cause stress to the cells and even kill them.

• Infections: When germs (like bacteria or viruses) invade our body, they can harm cells directly or cause inflammation. This can also lead to tissue damage.

When cells get hurt, they can die in one of two ways:

• Apoptosis: This is a planned way for cells to die when they are no longer needed.
• Necrosis: This is when cells die unexpectedly because of injury.

Both of these processes can cause inflammation, which can lead to even more damage to the tissues. Over time, this ongoing damage can lead to long-lasting diseases or organ failure.

For example, if someone drinks a lot of alcohol for a long time, it can hurt the liver cells. This injury can eventually cause a serious condition called cirrhosis.