Glossary of Terms. Bronchus / Bronchi / Bronchioles. The airways of the lungs. When a person takes in a breath of air, the air travels through the nose or mouth, into the larynx, then into the trachea, which is the main passageway into the lungs. The trachea divides into a right and left main bronchus.
Plant and animal life, atmosphere and water are the major causes of weathering. Weathering breaks down and loosens the surface minerals of rock so they can be transported away by agents of erosion such as water, wind and ice. There are two types of weathering: mechanical and chemical.
When physical agents cause the rocks to break into smaller pieces or fragments, it is called mechanical weathering. There are different causes of mechanical weathering that includes plants and animal activity (biological), fracturing and abrasion.echanical weathering involves physical activities leading to break down of rocks and chemical weathering involves natural chemical reactions leading to decomposition of the rocks.