Answer:
The <em>brain stem</em> is a bundle of nervous tissue at the base of the brain that connects the cerebrum to the spinal cord and sends messages between different parts of the body and the brain
Explanation:
Answer:
I would say Hydrogen because it makes 51% of the cell constituents.
A. bundles of microtubules that separate to opposite poles of a cell - CENTRIOLESB. prepares protein-packed vesicles for release outside of the cell - VESICLESC. small storage sacs containing water, food, and waste - VACUOLESD. rough and smooth organelle that produces protein, steroids, and lipids - ENDOPLASMIC RETICULUME. tiny sacs at the end of the ER which contain protein - GOLGI COMPLEXF. chains of protein fibers that provide support and shape - CYTOSKELETONG. powerful enzymes used to process cellular activity - LYSOSOMES & PEROXISOMESH. whip-like structures on cells that are used for movement - FLAGELLAI. produces and assembles proteins - RIBOSOMES im not really sure but hope this help
Metamorphic rocks can be formed by D) <span>all three types of rocks, igneous, sedimentary, and metamorphic</span>
Answer:
<h2>
Calcium ions</h2>
Explanation:
The actin and myosin are the myofilaments which are involved in the contraction and relaxation of the muscle. The actin is thin filaments and contains the attachment site for the myosin but the site is blocked by the tropomyosin and troponin proteins.
When calcium ions present in the muscle binds to the troponin molecules, it changes the conformation of the tropomyosin. This change exposes the attachment site of the myosin and then the myosin binds the troponin and causes Powerstroke and leads to contraction of a muscle.
Thus, Calcium ions is correct.