Answer:

Explanation:
The phospholipid bilayer is also known as the cell membrane. It covers cells and regulates the transport of substances. Certain ones can pass and others cannot, depending on certain factors like size and polarity.
Smaller substances tend to diffuse or move across the membrane quite easily. However, larger molecules have a much harder time. Many depend on special proteins embedded in the membrane. These are called transport proteins and they form a channel so large molecules can still move in or out of the cell.
So, salt, water, and fats do not contribute to the movement of larger molecules, but <u>channel or transport proteins do and choice A is correct. </u>
<span>Basically, the breeder selects individuals with desired traits (high milk yields, lots of wool etc) and keeps breeding then until the descendants display a very exaggerated set of traits.
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The <u>urethra</u> is an organ which communicates with the lower bladder in order to enable excretion of urine from the body of a living organism.
<h3>What is an excretory system?</h3>
An excretory system refers to a living system that is saddled with the responsibility of removing waste products from the body of a living organism, so as to prevent damage to the body and help maintain homeostasis.
Based on scientific information, the <u>urethra</u> is an organ which communicates with the lower bladder in order to enable excretion of urine from the body of a living organism.
Read more on urethra here: brainly.com/question/877660
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