I think the presence of a signal affect the expression of the structural enzymes in that it stops the production of the structural enzymes. Without the signals, the structural enzymes are produced. Genomic DNA contains both the structural genes that encodes products that serve as cellular structures or enzymes, and regulatory genes, which encode products that regulate the expression. In multicellular organisms allows for cellular differentiation while in single celled organisms like prokaryotes , regulation ensures that a cell's resources are not wasted making proteins that the cell does not need at that time.
The nucleus is considered to be the boss of the cell because of these two reasons:
1. The nucleus contains the hereditary material or also known as the DNA.
2. It is responsible in the coordination of the activities of the cells, such as growth, metabolism, protein synthesis, and cell reproduction or division.
Answer:
A) fish, snail, and plants
Explanation:
Answer: [B]: " a muscular foot ".
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"Every mollusk has a head, body, and <u> muscular foot </u> . "
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Hope this helps!
Best wishes!
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