Not familiar with that quince but it seems to have a pattern of leves on opposite sides of the stem but one side may have been broken off and replacement leaves have started from the collar cells where it was broken off
Those remind me of the smaller shoots on many plants that will form into complete branches when there's enough distance (through pruning or natural growth) from the main growing tip. Apparently the growing tips of many plants excrete a hormone that keeps potentially competitive branches from developing too close together.
Poop goes in a willow feeder. Wipe with this tiny ad: