How does the body create a difference between atmospheric and intrapulmonary pressures to cause air flow to and from the lungs

Pink fur (p) is dominant to purple fur (p) in hamsters. two heterozygous pink hamsters are crossed. what is the probability that these two parents will have an offspring with purple fur? 2/4, 1/2 or 50% 1/4 or 25% 3/4 or 75% 4/4 or 100% there is no chance for this type of offspring

Crossing over is a method of (blank)?

In a leaf, dermal tissue a) stores food b) stores carbon dioxide c) releases oxygen into the air d) transports water from the roots