The function of the collar cells of sponges function is to:
a. secrete a matrix that supports the body of the sponge
b. filter and engulf food
c. digest food
d. produce eggs and sperm
e. attach the sponge to a solid surface
b
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Active -galactosidase enzyme is observed only in E. coli growing in the presence of lactose. One hypothesis is that the enzyme is always being produced, but is produced in an unstable form that breaks down rapidly in the absence of lactose (hypothesis 1)
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