1单元 - 1F

The wrist is a complex joint located between the hand and the forearm, allowing for movement and flexibility. It consists of multiple small bones called carpal bones, along with ligaments, tendons, and nerves. The wrist enables various motions such as flexion, extension, abduction, and adduction, facilitating activities like grasping, gripping, and manipulating objects. It plays a crucial role in fine motor skills and is essential for many daily tasks. Understanding the anatomy and function of the wrist is important for maintaining its stability, preventing injuries, and ensuring optimal hand and arm functionality.

Blood is a vital fluid in the human body that circulates through a network of blood vessels, delivering oxygen, nutrients, and hormones to cells while removing waste products. It consists of red blood cells, white blood cells, platelets, and plasma, and plays a crucial role in maintaining homeostasis, defending against infections, and transporting essential substances throughout the body.

A cut is a break or opening in the skin caused by something sharp, like a knife or glass. Cuts can vary in depth and seriousness, from small superficial ones that only affect the surface to deeper ones that may penetrate layers of tissue. They often result in bleeding, pain, and sometimes swelling around the affected area. Treatment for cuts involves cleaning the wound with soap and water to prevent infection, applying pressure to stop bleeding, and covering it with a clean bandage. In some cases, medical attention may be necessary, especially for deep cuts that may require stitches to close properly.

A sprain is an injury to a ligament, which is the tissue that connects bones to each other in joints. It typically happens when a joint is forced beyond its normal range of motion, causing the ligament to stretch or tear. Sprains commonly occur in the ankles, wrists, or knees and can result in pain, swelling, and difficulty moving the injured joint. Depending on the seriousness, sprains may require rest, ice, compression, and elevation or medical attention such as physical therapy to fully recover.

A bruise is a mark on the skin caused by injury, where blood vessels underneath the skin break and leak blood into the surrounding tissue. Typically, bruises appear as discolored patches ranging from blue and purple to yellow or green as they heal. They are often tender to the touch but usually fade away over time as the body reabsorbs the leaked blood and repairs the damaged tissue.