The cytoplasm of adjacent sieve tube members extend from cell to cell through regions filled with small pores called plates.

➢ The cytoplasm of adjacent sieve tube members extend from cell to cell through regions filled with small pores called sieve plates.

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