Type your answer here... i dont know
the yock sac supplies nutrients
its the ovary
Type your answer here... i dont know
The yolk sac is initially what gives the baby nutrients before the umbilical cord is formed
The appendix.
The appendix.
There isn't an air sac in the lungs, They're alveolis that take in the air and expand to improve their surface area, causing your diaphragm to expand and shrink when you breathe, but the function is to allow you to respire.
The appendix.
To lower their body density, making it easier to fly.
the function of the pollen sac is to produce pollen (pollen grains). The pollen sac is the microsporangium of a seed plant in which pollen is produced. Most plants except coniferous plants contain four (4) pollen sacs.
The pericardial sac (or pericardium) is a dual-walled sac that contains the heart and the roots of the great vessels (vena cavae, pulmonary arteries, pulmonary veins, aorta, brachiocephalic arteries and veins, carotid artery and subclavian artery).
Friction around the heart and possible damage.