Bivalves are protostomes, as they belong the to phyla Protostomia. They are freshwater/marine molluscs, whose body is covered by a protecting shell. They do not have a head, and some of their examples include oysters, clams, mussels etc.
Answer:
through a tiny hole or slit in a metal plate to isolate light from a single area or object.
Answer:
b. the contractile unit between two Z discs
Explanation:
A sarcomere is the functional and mechanical unit of striated muscle structure, is formed of thin filaments (two strands of actin and one strand of regulatory protein) and thick filaments (myosin). <em>They have the ability to contract in unison coordinating the muscles’ contractions. As you can see in the image added these units are located between Z discs. </em>
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oxygen
Your cells need oxygen to convert the nutrients you eat into energy for your body. In the process of making that energy, some waste products are produced. One of the main waste products is a gas called carbon dioxide.