(4) The attachment of the pyrimidine base to the ribose phosphate ring is catalyzed by orotate phosphoribosyl transferase (OPRT) and PRPP provides the ribose-5-phosphate moeity. Hydrolysis of the PP i that is split off of the PRPP makes this reaction irreversible.
Red Squirrels shed their coats twice a year, switching between a thinner coat in summer and a darker, thicker winter coat. 6. Males may live in an area of up to 17 hectares of woodland... thatâs about the same size as 34 football pitches! 7.
How do you keep baby squirrels warm? Use cotton, like old t-shirts, towels, or old sheets). Cut them up  in smaller squares and change them daily or when soiled. Put enough  fabric int he cage so that the squirâ¦rel can cuddle up inside to  stay warm. Get a heating pad/lamp. Make sure to leave room in the  cage for the squirrel to move around if they get too warm.