Nonpolar molecules can pass through the plasma membrane with relative ease. Even larger nonpolar molecules, such as steroid hormones, can pass through the plasma membrane easily. Passing through the membrane without the need for assisting proteins is known as passive diffusion.

Facilitated diffusion involves the use of membrane channel proteins to allow molecules to pass (example: potassium leak channels). Active transport requires the metabolism of ATP to pump a molecule against its concentration gradient (example: sodium-potassium pump). Secondary active transport uses ATP to generate an electrochemical gradient, then uses the gradient to transport molecules and perform work (example: ATPase).

Actin is what makes up microfilaments. Chitin is indeed in cell walls of fungi. Cellulose is the main ingredient to plant cell walls and peptidoglycan are found in the cell walls of cyanobacteria and bacteria. Also, cellulose is made of polysaccharides, therefore, this is also an incorrect answer because it is a component of the cell wall.

The fluid mosaic model says that proteins can extend all the way through the phospholipid bilayer of the membrane. There are peripherial, integral, and transitional proteins. Therefore, these proteins are various sizes and lengths. 

Lipids can diffuse freely across the cell membrane, because the cell membrane is made up of lipids. Ions will not be able to pass through the hydrophobic section of the membrane, because it is polar. Chloride is an ion. Water is polar and also won't be able to pass through the hydrophobic section of the membrane. Sucrose is too big to freely diffuse into the cell. 

A cell must exchange molecules and ions with its surroundings.  This process is controlled by the selective permeability of the plasma membrane.  Passive transport requires no energy from the cell; molecules like water can diffuse into and out of the cell through the phospholipid bilayer freely by way of osmosis.  Other molecules and ions, like sodium, are actively transported across the phospholipid bilayer.  This requires ATP created by the cell.  Active transport moves solutes against their concentration gradients, which is why it requires energy. 

Tonofibrils are groups of keratin tonofilaments (intermediate filaments) most commonly found in the epithelial tissues, not endocrine tissues, and which play an important structural role in cell makeup.

Glycolysis happens in the cytosol (the fluid containing the organelles) of the cell. The next step in cellular respiration, the citric acid cycle, occurs in the mitochondria.

Fermentation oxidizes molecules of NADH to NAD⁺ so the cell can have oxidizing agents for any subsequent glycolysis reactions. It does not, however, produce any usable energy in the process.

Fermentation leads to the production of ethanol in yeast cells and lactic acid in muscle cells.

Glycolysis occurs in the cytosol of cells. Once finished, the two pyruvate products are transported into the mitochondria to go through the citric acid cycle, at a cost of 1 ATP per pyruvate. Neither the nucleus, nor the endoplasmic reticulum have any function in glycolysis or the citric acid cycle.

The conversion of glucose to two pyruvate molecules in glycolysis produces a net total of two direct ATP. When fructose-1,6-bisphosphate enters glycolysis, it bypasses the two steps involved that normally cost one ATP each, therefore, there is no required input and the net total is four produced ATP.

We have to remember that each step beyond the conversion of fructose-1,6-bisphosphate to glyceraldehyde-3-phosphate and dihydroxyacetone phosphate happens twice, or we would come up with two ATP created.