Endocytosis is the process where a cell imports large things into the cell. All forms of endocytosis are active, meaning the cell expends ATP while performing this process. Specifically, a style of endocytosis called phagocytosis involves a cell surrounding the target material with its cell membrane and encloses it while bringing it into the cell. This enclosed membrane bound material then pinches off into a spherical 'vesicle'. An example of this can be a cell importing a protein into its cellular space.
Change in the external Environment may resulted in the changing in the population of beetles.
The reproductive system is a group of sex organs that work together for the purpose of sexual reproduction. Hope this helped!