Subunits of skeletal muscle fibers that are composed of sarcomeres are called . Subunits of skeletal muscle fibers that are composed of sarcomeres are called . myofibrils transverse tubules sarcolemmas myofilaments

The correct answer is myofibrils

Explanation:

The fundamental part of the muscle cytoskeleton is made up of myofibrils that are the contractile elements of skeletal muscle cells.Muscle fibers are made up of myofibrils, membranes, and cytoskeletal networks that anchor contractile fibrils to the sarcolemma. Myofibrils are composed of repeating contractile units known as sarcomeres and are perhaps the most ordered macromolecular structures in eukaryotic cells. Myofibrils are made up of actin and myosin filaments that are large polymerized protein molecules responsible for actual muscle contraction.

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.

both male and female gametes are produced by meiosis of the germ cells. therefore, both male and female gametes are haploid. one male and one female gamete unite during the fertilization to form the diploid zygote. in seed bearing plants, pollen grain is the male gametophyte, which produces sperm cells.