Basic Bio, I will rate you, What are the two components of the cytoplasm? What i

ID: 87669 • Letter: B

Question

Basic Bio, I will rate you,

What are the two components of the cytoplasm? What is the difference between intracellular fluid and extracellular fluid? What is the difference between extracellular fluid and interstitial fluid?

What are the three components of the cytoskeleton? What are the subunits that comprise each? Which cytoskeletal filaments support microvilli? Cilia? Which are responsible for mediating pseudopodial movement?

What is a brush border? Where would you expect to see a brush border in the body? What is a brush border enzyme?

How are intermediate filaments involved in cell-cell attachment?

What are the two main types of microtubule-associated proteins (MAPs)? If a cell makes a protein near the nuclear membrane and needs to transport this protein towards the plasma membrane, which of these two MAPs would mediate this transport?

Taxol is a long-standing treatment for cancer. How does it work? What are its drawbacks? What would be a better way to treat cancer?

Cigarette smoking can decrease the motility of cilia in the respiratory tract. What complications could this cause?

Explanation / Answer

1. Cytoplasm is a jelly-like substance and it is made up of eighty percent water and is usually clear and colorless. Cellular organelles are suspended in the cytoplasmic fluid. The major components of cytoplasm are cytosol, organelles and cytoplasmic inclusions.

Cytosol

Cytosol makes up about 70% of the volume of the cell. It is composed of water, salts and organic molecules, mixture of cytoskeleton filaments, organic and inorganic molecules and water. It also contains protein filaments that make up the cytoskeleton, and also soluble proteins and structures like ribosomes, proteasomes are also present.

Organelles

Organelles mean "little organs", that are membrane bound. They are present inside the cell and perform specific functions that are necessary for the survival of the cell. Cellular organelles like mitochondria, endoplasmic reticulum, Golgi apparatus, vacuoles, lysosomes and chloroplasts in plant cells.

Cytoplasmic Inclusions

The cytoplasmic inclusions are tiny particles suspended in the cytosol. A vast range of inclusion are present in different cell types. Lipid droplets are best example of inclusions,

Intracellular fluid

Extracellular fluid

Within the body cells - cytosol

Situated outside the cells

Contains proteins and amino acids and has a concentration gradient

Presents with more ions

3. Interstitial fluid is one of the components of the Extracellular fluid. Interstitial fluid situates within the spaces or gaps of body tissues, interstitial fluid bathes the cells of the tissues. This provides the cells of the body with nutrients i.e delivering materials to the cells, intercellular communication, as well as removal of metabolic waste.

4. The cytoskeleton is responsible for cell shape and motility of organelles within the cell. There are 3 main structural components of cytoskeleton are – microtubules, microfilaments and intermediate filaments.

Microfilaments: microfilaments are fine, thread-like protein fibers, 3-6nm in diameter. They are composed predominantly of a contractile protein called actin.

Microtubules: microtubules are cylindrical tubes, 20 – 25nm in diameter. They are composed of tubulin subunits. They determine the cell shape.

Intermediate filaments: Intermediate filaments are about 10nm in diameter and provides tensile strength for the cell.

5. Microfilaments are support microvilli, intestinal epithelial cells have protrusions from their surface called microvilli. They increase the surface area of the intestinal cells to maximize their ability to absorb nutrients. Microtubules help in movement of substances within the cell and involved in powering whole-cell movement by cilia and flagella.

6. Inside of the cells, actin exists in two states, the monomeric protein, called globular actin (G-actin) and the 6 nm filament, called F-actin (for filamentous actin). Each microfilament has a fast-growing and slow-growing ends. Microfilaments can produce protrusions on the cell surface called pseudopods by the rapid polymerization of actin monomers.