Which of the following statements about muscles and the muscular system is true?
O The three types of muscle tissue are skeletal muscle, smooth muscle, and involuntary
muscle.
O Muscles always work independently to move parts of the body.
All muscle action is voluntary, or able to be consciously controlled.
OSmooth muscle moves food through the digestive system.

b. read the phase at the intersection of any given temperature and pressure.

step 1: nitrogen fixation- conversion of atmospheric no₂ into forms useful to plants by lightning, bacteria, and cyanobacteria.

step 2: nitrification-process of converting ammonia to nitrite or nitrate.

step 3: assimilation-plant roots absorb new form of nitrogen.

step 4: ammonification-conversion of organic nitrogen to ammonia by bacteria involved in decomposition.

step 5: denitrification-bacteria turns the decomposed matter back into n₂o, which is released into atmosphere; repeat cycle.