Which one of the following statements about the cytoskeleton is correct? a. the width of a cytoskeletal element is directly proportional to its length. b. intermediate filaments are wider than microtubules. c. a cell can adjust the lengths of most of its cytoskeletal elements as needed. d. cytoskeletal elements have a common diameter, but differ in type by their lengths. e. actin filaments are always longer than microtubules.

The dna in a cell’s nucleus encodes proteins that are eventually targeted to every membrane and compartment in the cell, as well as proteins that are targeted for secretion from the cell. for example, consider these two proteins: phosphofructokinase (pfk) is an enzyme that functions in the cytoplasm during glycolysis. insulin, a protein that regulates blood sugar levels, is secreted from specialized pancreatic cells. assume that you can track the cellular locations of these two proteins from the time that translation is complete until the proteins reach their final destinations. for each protein, identify its targeting pathway: the sequence of cellular locations in which the protein is found from when translation is complete until it reaches its final (functional) destination. (note that if an organelle is listed in a pathway, the location implied is inside the organelle, not in the membrane that surrounds the organelle.)

Below, the levels of organization in a multicellular organism are shown from least to most complex. which level of organization can be described as several different types of tissues working together to perform a common task?

What is one way intensive agriculture can contribute to climate change? a. tree loss to agriculture increases earth's albedo b. livestock manure absorbs greenhouse gases c. large herds of livestock release greenhouse gases d. fewer trees are available to replenish petroleum stores appex