C Because Limestones are Formed In shells and corals so it is subjected to intense heat and any times of pressure
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Answer:
The soil could kill the plants in the area and the consumers will lose there food and the organisms will die off or go extinct.
Explanation:
The correct answer is B) Treaties expanding International Trade
After the second world war, the world has gradually opened up to one another for trade and opportunities.
We see that in the development of the World Trade Organization, as well as the NAFTA (North American Free Trade Agreement) between Canada, US, and Mexico and probably the most successful example in the European Economic Zone.
Answer:
<u>d. Transport proteins within the membrane serve as a tunnel for molecules to enter the cell.
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Explanation:
Solutes are typically moved across the cell through either passive or active transport. The cells, surrounded by a bilipid layer or plasma membrane is amphiphlic- its polar, hydrophilic lipid heads face outwards, while their non-polar hydrophobic lipid tails face inwards towards each other.
While lipid-soluble molecules move across the layer easily, it is also difficult for charged and also large molecules to move across its surface, into the cell. Transmembrane channels, <u>embedded within the membrane</u>, help to maintain selective permeability as transport proteins, pores and gated channels. Simple diffusion happens as a method of passive transport in cells through plasma membranes.
The solutes travel through the plasma membrane in the process of diffusion from regions of high concentration to regions of low concentration; this occurs without the use of energy. <u>Molecules moving against their concentration require active transport mechanism to cross the membrane</u>.
