What is the purpose of the glycoprotein spikes found on some enveliped viruses

Which of the following statements is true of enzymes? a)they dont provide an active site for substrates to bind in a reaction b)they act on a specific type of substrate in a reaction c)they unusable after a reaction d)they change shape after a reaction

Below are the three main organs that make up the plant body. what is the main function of the structure that is identified as b in the picture above? it anchors the plant.it produces food.it absorbs nutrients.it supports the plan

What are the characteristics of subsystem