The puppies heads are often to big to fit through their mothers birth canal. They may get birth defects like flat chests, if their face are wrinkly they get acne and eye problems, and they are prone to skeletal disorders like hip dysplasia.
A branch or leaf and here is a link to some flash cards i found
https://quizlet.com/45759526/developmental-anatomy-flash-cards/
The answer is written on the pic I sent you with this