A lymphocyte is a type of white blood cell. White blood cells are part of your immune system and help your body fight off diseases, including infections and cancer. There are two main types of lymphocytes â B cells and T cells. B cells make antibodies that attack bacteria and toxins in the body.
- Mud, sand, and volcanic ash can make sedimentary rocks. bones leaves, stems, and other remains of living things. - Geologists classify metamorphic rocks according to the arrangement of the grains that make up the rock. - Metamorphic that have their grains arranged in parallel layers or bands are said to be foliated.
Sand dune cross-beds can be large, such as in the Jurassic-age erg deposits of the Navajo Sandstone in Canyonlands National Park. In geology, the sedimentary structures known as cross-bedding are the (near-) horizontal units that are internally composed of inclined layers. This is a case in geology in which the original depositional layering is tilted, and the tilting is not a result of post-depositional deformation.