A mule is the result of a horse that has been bred with a donkey. Mules are generally sterile, meaning that they cannot be bred with each other in most cases. They also have 63 chromosomes. In appearance, mules may look very similar to donkeys. They also have stiff hair. Much like donkeys, mules are strong animals and tend to have calmer personalities.
Air Embolism. An air embolism is an obstruction in a vein or artery caused by a bubble of gas. Air enters the circulatory system when the pressure gradient favors movement of air or gas from the environment into the blood. A venous air embolism is the most common form of air embolism.
In rare instances, blowing air into the vagina during oral sex can cause an air embolism. In this case, the air embolism can occur if thereâs a tear or injury in the vagina or uterus. The risk is higher in pregnant women, who may have a tear in their placenta.