Based on DNA's structure and function, why did Meselson and Stahl choose to grow E. coli in broths of nitrogen isotopes?
A The bacteria's phosphate groups would be replaced by the
nitrogen
OB. The nitrogen would be incorporated into deoxyribose.
a
C. The nitrogen would influence bonding between base pairs.
D. The nitrogen would be incorporated into the DNA
nucleotides.

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.

the answer would be..

b. sucking

here is the answer

water, ice, acids, salts, plants, animals, and changes in temperature are all agents of weathering. weathering is the breaking down or dissolving of rocks and minerals on earths surface. once a rock has been broken down, a process called erosion transports the bits of rock and minerals away.