Heartwood differs from sapwood in
In perennial woody trees, the region which consists of dead elements and do not conduct water but provides mechanical support is called heartwood.
The peripheral region, which is soft and lighter in color and consists of living cells is known as the sapwood. It is involved in the conduction of water and minerals.
Both heartwood and softwood have rays, fibres, vessels and parenchyma. Both heartwood and sapwood are susceptible to pests and pathogens, but sapwood has living cells making it more susceptible. Hence, the answer will be: having dead and non-conducting elements.