2. Which of the following is NOT a characteristic of a Eurkaryotic Cell?

A. has a nucleus

B. has membrane bound organelles

C. has DNA floating in the cytoplasm

D. has a cell membrane

C

Explanation: Eukaryota cells have a nucleus surrounded by a nuclear envelope that consists of two lipid membranes, The nucleus holds the Eukaryota cell's DNA. Prokaryotic cells do not have a nucleus; rather, they have a membrane-less nucleoid region (open part of the cell) that holds free-floating DNA.

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products