Which of the following movement structures help cells "crawl" using extensions of the cytoplasm?

They are hollow structures made up of proteins known as the tubulins.

Explanation:

Filopodia -Cells in your body can send out extensions from the cytoplasm like tentacles, called filopodia. They use these to help feel their way around as they move, gather nutrients and communicate with each other.

Pseudopodia -Some small single-celled organisms such as amoeba use cytoplasmic extensions to crawl around to scavenge for food. These extensions are sometimes referred to as false feet; the more technical term for these false feet is pseudopodia.

Dendrites and Axons -Nerve cells have two types of cytoplasmic extensions that are used for receiving signals from nearby cells and for passing information on to other cells. A nerve cell or neuron has a large cell body with small cytoplasmic extensions branching off from it called dendrites.

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this protocol provides a detailed procedure for chromatin immunoprecipitation (chip) to study the dna-protein interactions.

then that particular organisms become extinct.