Internal hemorrhoids are sometimes painful if they extend outside the anus, or if the blood vessels are clotted (called thrombosed hemorrhoids). 1  First degree: the hemorrhoids remain inside at all times. 2  Second degree: the hemorrhoids extend out of the rectum during a bowel movement but return on their own.
Answers. Best Answer: Rocks can be broken down by physical or chemical weathering. Physical weathering is the cracking, breaking up, and grinding down of rocks into smaller pieces while maintaining the same mineral composition. This type of weathering is caused by a number of different factors. Changing temperatures cause rocks to crack and flake, ice splits rocks open, living things dig or pry open rocks, gravity causes rocks to fall and shatter, and abrasion breaks down rocks with solid particles like sand.
building and volcanic activity. At the same time, external processes continually break rock apart and move the debris to lower elevations, as shown in Figure 1. The breaking down and changing of rocks at or near Earthâs surface is called weathering. Weathering is a basic part of the rock cycle and a key process in the Earth system. There are two types of weatheringâmechanical and chemical. Though these processes are different, they are at. work at the same time. Figure 1 Weathering Ice, rain, and wind are slowly breaking down the rock in this mountain.