Referigerator Vent Pipe?

[Steppy]

I opened the external access panels top the back of the refrigerator today on the TM I just bought and I observed what appears to be a plastic dryer vent pipe and assume it's to vent hot air from the refrigerator. The plastic is very brittle and this needs to be replaced. Could I use a metal vent pipe? Is there a fan at the bottom?

Thanks. I appreciate the good advice I get here.

I know the picture is upside down, the original is not and I cannot figure how to correct this. I even reversed the original picture hoping it would be reversed again on here and be correct. Any suggestions?