These genetic variants are believed to cause changes in the way the bodyâs T cells behave. T cells are immune system cells that normally fight off harmful invaders, such as viruses and bacteria. In people with psoriasis, however, T cells also attack healthy skin cells by mistake. This immune system response results in a range of reactions, including: 1  enlargement of blood vessels in the skin.  increase in white blood cells that stimulate the skin to produce new cells more quickly than usual.
Teeth. Zebra have several types of teeth that help them survive in their habitats. In the front of their mouths, zebra use their strong incisors for biting off grass and other vegetation. In the rear of their mouths, zebra have molars and premolars to grind down their food.
Food is scarce, so a zebra (and everything else) has to eat what they can find. Due to the climate, most of the available grass is very dehydrated, withered, sometimes dead, and a lot less substantial than green grass, but itâs better than nothing, especially if they have not eaten in a while or have been on the move. A zebra would much rather eat moist, healthy, thick grass.