When you want to move a part of your body, your brain sends a signal to the muscles

The muscles Contract and relax randomly

Contract and pull on bones directly

Contract and pull on tendons, which pull on the bones

Contract and pull on tendons, which pull on bones

Explanation:

Muscles don't attach directly to bones. The tendons throughout our body serve as a connective tissue, connecting the two. Skeletal muscles, which seem to be attached to bones, are still only held there with the help of muscles.

step 1 ammonium can be absorbed by plants, but some is converted into nitrates which are better for plants to absorb. this is called nitrification. 2. step 2 the deer eats the plants and uses the nitrogen-containing proteins for cell growth. 3. step 3 bacteria in the soil conduct nitrogen fixation to convert nitrogen gas from the atmosphere into ammonium. 4. step 4 some of the nitrates are absorbed back into plants, but denitrification breaks down the nitrates into nitrogen gas released back into the atmosphere. 5. step 5 nitrogen is found in the urine, which gets broken down into ammonium through the process of ammonification. 6. step 6 plants absorb the ammonium and begin assimilation, the process to add the nitrogen to protein.