Chemical factors: This is due to internal stimuli. Changes in the blood such as decrease in O2, increase in CO2 and decrease in PH cause impulse in the carotid artery which stimulates the respiratory centers in the medulla and cause breathing.
Mechanical factors: also called external stimuli. Compression of the fetal chest during delivery forces small amount of lung fluid out of the lungs. This increase in pressure in the chest draws air into the lungs.
Bonds issued by the U.S. treasury are back by the federal reserve and claim to have no credit risk. Agency bonds also usually have low credit risk. otherwise you just have to look at the bond before you invest and find out what dink of credit risks are involved.
Answer:
photosynthesis
Explanation:
it takes carbon into the biosphere
Answer:
New virgin queens develop in enlarged cells through differential feeding of royal jelly by workers. When the existing queen ages or dies or the colony becomes very large, a new queen is raised by the worker bees. When the hive is too large, the old queen will take half the colony with her in a swarm.
Explanation:
