case study; Evolution does not always lead to more advanced species. Evolution is simply a description of the way change occurs in biological creatures over many generations in order to better exploit a certain environment. Evolution sometimes leads to progress, but it sometimes leads in the opposite direction. For instance, the Texas blind salamander has lost his eyes after many generations of evolution due to the uselessness of eyes in the dark caves where he dwells

.questions;

from the case study; answer the following questions appropriately

1. Following internalization, vesicle-bound materials are transported to?

2.justify accordingly why; Receptor down regulation leads to a decrease in the sensitivity of the cell towards further stimulation.

3what is the interesting component do you know about Dynamin?

4)interelate the roles of the AP2 and the clathrin-mediated endocytosis

5) A molecule of clathrin has a ______________ structure;demonstrate

6)how do the roles of the clathrin and Receptor-mediated endocytosis (RME) overlap?

7)propse and explain the nature of the operations of the receptor-mediated endocytosis in regard to the cell uptakes extracellular material

8)after travelling through the late endosome,what is the fate for materials ingested by endocytosis?explain

9)explain the feature of the Transformation from an early to a late endosome in the pH

10)position the Late endosome in the nucleus

endosomes; Following the internalization of materials from the extracellular environment to the intracellular environment, the vesicle bound materials are transported to endosomes.

There are two different types of receptors involved in the endocytosis. The endocytosis mediated by the second group of receptors leads to their destruction, called the receptor down regulation. This decreases the sensitivity of the cell towards further stimulation.

possession of accessory protein; Dynamin is a large GTP^-binding accessory protein that aids in the release of clathrin^-coated vesicle from the membrane on which it is formed.

Step-by-step explanation

1. endosomes; Following the internalization of materials from the extracellular environment to the intracellular environment, the vesicle bound materials are transported to endosomes.

2. There are two different types of receptors involved in the endocytosis. The endocytosis mediated by the second group of receptors leads to their destruction, called the receptor down regulation. This decreases the sensitivity of the cell towards further stimulation.

3.possession of accessory protein; Dynamin is a large GTP^-binding accessory protein that aids in the release of clathrin^-coated vesicle from the membrane on which it is formed.

4. AP2 adaptor molecules are associated with clathrin coated pits formed in the plasma membranes as a result of receptor^-mediated endocytosis.

5. triskelion; A molecule of clathrin has three heavy and three light chains joined at the center, forming a three^-legged structure called triskelion.

6. Substances bound to receptors enter a cell by receptor^-mediated endocytosis and collect in specialized domains of the plasma membrane called the 'coated pits'. Clathrin is present on the electron^-dense coat of these pits.

7. The specific uptake of extracellular materials in which they are bound to external surface of the plasma membrane, is known as receptor^-mediated endocytosis.

8. lysosome; After endocytosis materials reach the late endosome, where the bound ligands are concentrated. After late endosome the materials reach lysosome for further processing.

9. Transformation from an early endosome to a late endosome is characterized by a decrease in the pH and a major change in the internal morphology of the structure.

10. The complex network of tubules and vesicles is collectively known as endosomes. There are two classes of endosomes: early endosomes, located near the cell periphery, and late endosomes, located near the nucleus.