Metamorphic grade is a general term for describing the relative temperature and pressure conditions under which metamorphic rocks form. As the temperature and/or pressure increases on a body of rock we say that the rock undergoes prograde metamorphism or that the grade of metamorphism increases.he original rock that has undergone metamorphism is called the protolith. Protolith can be any type of rock and sometimes the changes in texture and mineralogy are so dramatic that is difficult to distinguish what the protolith was. 1  Note that diagenesis and weathering are also a changes in form that occur in rocks.
Within the nephron (the functional unit of the kidneys), filtration occurs in the glomerolus. The filtered fluid is called filtrate. Reabsorption of filtrate occurs in a few places within the nephron, however, the majority of reabsorption takes place in the proximal convoluted tube.
The nephron has three major parts: the glomerulus, the Bowman's Capsule, and the tubule (which is further divided into the promimal and distal tubule and the Loop of Henle). Blood enters the kidney from the renal artery and moves into the glomerulus, where filtration occurs.he collecting duct prepares the urine for transport out of the body, it is collected in the renal pelvis where it eventually enters the ureter. From there it goes to the bladder. Colouring Instructions 1. Colour the renal artery red, and continue the flow of blood through the capillaries.