Gas exchange happens in the spongy mesophyll tissue of the leaf. Spongy mesophyll cells are covered by a thin layer of water and loosely packed. When the plant is photosynthesising during the day, these features allow carbon dioxide to diffuse into the spongy mesophyll cells, and oxygen to diffuse out of it.pongy mesophyll cells are covered by a thin layer of water and loosely packed. When the plant is photosynthesising during the day, these features allow carbon dioxide to diffuse into the spongy mesophyll cells, and oxygen to diffuse out of it.
In biometrics and forensic science, minutiae are major features of a fingerprint, using which comparisons of one print with another can be made. Minutiae include: 1  Ridge ending â the abrupt end of a ridge. 2  Ridge bifurcation â a single ridge that divides into two ridges. 3  Short ridge, or independent ridge â a ridge that commences, travels a short distance and then ends.
Petechiae are pinpoint-sized hemorrhages of small capillaries in the skin or mucous membranes. Petechiae result from tiny areas of superficial bleeding into the skin.They appear as round, pinpoint-sized dots that are not raised. The color varies from red to blue or purple as they age and gradually disappear. Petechiae commonly appear on the lower legs, but may be distributed all over the body.etechiae are pinpoint-sized hemorrhages of small capillaries in the skin or mucous membranes. Petechiae result from tiny areas of superficial bleeding into the skin.