<span>Flexible joints are A. important to prevent athletic injury. It is quite important to stretch and warm up before exercising so as not to hurt yourself and your body and muscles. Flexibility is relevant for everyone, not just cross-training athletes. It doesn't occur naturally, you have to train to get there. It is important for everything, not just running. </span>
Natural active immunity arises from an exposure to antigens, while natural passive immunity <span>arises from the passage of antibodies across the placenta or breast milk. </span>A mother breastfeeding her baby is an example of passive natural immunity.
Passive natural immunity is type of immunity in which antibodies are passed from the mother to fetus or child. In case of breastfeeding antibodies are passes through the breast milk.