Question

timed test this test has a time limit of 1 hour. this test will save and submit automatically when the time expires. warnings appear when half the time, 5 minutes, 1 minute, and 30 seconds remain. multiple attempts not allowed. this test can only be taken once. force completion once started, this test must be completed in one sitting. do not leave the test before clicking save and subm this test does not allow backtracking. changes to the answer after submission are prohibited. your answers are saved automatically. remaining time: 57 minutes, 47 seconds. question completion status: question numbers from 1 - 46 moving to the next question prevents changes to this answer. question 4 the framework inside a cell that supports its shape and is made of 3 different types of protein a. endoplasmic reticulum b. cytoskeleton c. envelope d. mitochondria e. vesicle

Explanation:

The cytoskeleton is a network of protein filaments inside the cell that provides structural support and is composed of three main types of proteins: microfilaments, intermediate filaments, and microtubules. The endoplasmic reticulum is involved in protein and lipid synthesis, the envelope is related to viruses or cell - membrane structures in some cases, mitochondria are the power - houses of the cell for energy production, and vesicles are small membrane - bound sacs for transport.

Answer:

B. cytoskeleton