In order for plants and animals to be able to use nitrogen, N2 gas must first be converted to more a chemically available form. Review the picture of the nitrogen cycle. One type of organism is responsible for "fixing" nitrogen so other organisms can use the element. What organism is this?

Nitrogen fixing bacteria is the organism which is responsible for the fixing of atmospheric nitrogen into usable form for the plant.

Explanation:

Nitrogen fixing bacteria is a type of bacteria which fixes atmospheric nitrogen into ammonium and nitrates form. Plants are unable to take atmospheric nitrogen so it must be converted into available form i. e. nitrates and ammonium. Examples of nitrogen fixing bacteria are Cyanobacteria and Azotobactor etc. These nitrogen fixing bacteria lives in the root of the plant and makes symbiotic association.

answer; blending inheritnace;

the answer is: the „power stroke“ step.

muscle contraction can be divided into a few steps:

1. the release of ach (acetylcholine) in the synaptic cleft, binding of ach for its receptor and consequently opening of the ca channels.

2. the release of ca, binding of ca for the troponin

3. troponin shifting the tropomyosin, which was blocking the active site on the actin

4. myosin heads attaching to actin by breaking down atp to adp+ pi

5.   formation of the ‘cross-bridge’ on the active site of the actin filament by myosin head

6. “power stroke” -the cross bridge pulls actin, which slides over the myosin

9.     7. the release of adp completes the cross-bridge movement and atp attaches to myosin, breaking the actin-myosin cross bridge.