In Each of the Following Sentences, a Blank Space Appears

question 22

Multiple Choice

In each of the following sentences, a blank space appears where a verb should be. Select the letter of the correct helping verb and past participle form. Only after he moved did he realize that he ____ away his favorite photos.

• A) has throwed
• B) has thrown
• C) had thrown

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Definitions:

Root Hairs

Thin, hair-like extensions from a plant's root system that increase surface area for water and nutrient absorption from the soil.

Endodermal Cells

Cells that make up the endoderm, the innermost layer of cells in early animal embryos, which eventually forms the lining of the digestive and respiratory systems.

Aquaporins

Protein channels in cell membranes that facilitate the transport of water and, in some cases, small solutes across the membrane.

Active Transport

The movement of molecules across a cell membrane from a region of lower concentration to a region of higher concentration, requiring energy input usually in the form of ATP.