Someone please help I took the picture this is my last question on my homework

According to the image that represents a cell in the human body, the true statement is that structure 4 is the cell membrane that provides exchange of O₂ & CO₂.

Explanation:

In cells, the cell membrane acts as a semi-permeable barrier to the passage of substances, including nutrients and oxygen (O₂).

One of the functions of the cell membrane is to allow the exchange of O₂ —necessary for the cell— and carbon dioxide (CO₂), a product of cell metabolism that must be removed.

In the image, the structure identified with the number 4 corresponds to a cell membrane of human cells that provides this gas exchange.

The other options are not correct because:

a researcher conducts an experiment on the secretion of a particular hormone in mice. scientists inject mice with a substance that stimulates the production of the hormone. the scientists then test the levels of hormones produced by the mice. the tool used to measure the hormones consistently detects the levels at 10 points lower than the actual hormone levels in the mice. this tool makes measurements, but the measurements aren't .

explanation:

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