Answer:
B. The membrane lets certain substances move across it freely, while others must move through a “gate”.
Explanation:
Selective permeability is a property of cellular membranes that only allows certain molecules to enter or exit the cell. This is important for the cell to maintain its internal order irrespective of the changes to the environment. For example, water, ions, glucose and carbon dioxide may need to be imported or exported from the cell depending on its metabolic activity. Similarly, signaling molecules may need to enter the cell and proteins may need to be released into the extracellular matrix. The presence of a selectively permeable membrane allows the cell to exercise control over the quantum, timing and rate of movement of these molecules.
B because the diploids always line up in the middle on chromosomes
This illustrates <span>absolute threshold. The correct option among all the options that are given in the question is the second option or option "B".
</span><span>A spot in the middle of the retina that only contains cones is called the fovea. The correct option among all the options that are given in the question is the third option or option "C".</span>
A) 12 chromosomes in a gamete
B) 46 chromosomes in prophase 1!
Perspiration
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