Describe the structural compartmentation of mammalian cells and the differing functions of these compartments
Cells with a membrane-bound nucleus are categorised in the eukaryote super kingdom . Mammalian cells are one of four eukaryotic kingdoms, alongside Plantae, Fungi and Protista. Eukaryotes differ from prokaryotes in several ways, including their larger size, multicellular properties, the presence of a nucleus and membrane-bound organelles. Yet, it seems probable that eukaryotic cells evolved from prokaryotes, with the most likely explanation being the endosymbiotic theory.
When looking under a powerful microscope at the ultrastructure of a mammalian cell we can see that it is compromised of several components. These subunits work together to form effective cell structures, which assemble into a tissue, which in turn construct an organism.
Figure 1. The anatomy of an animal cell Source:
Mammalian cells differ in structure depending on the ways in which they have specialised to carry out particular functions. The typical eukaryotic cell includes the features illustrated by figure 1.
The plasmalemma is a partially permeable boundary which encloses the cytoplasm within the cell, separating it from the extracellular fluid outside. The cytoplasm is the ‘jelly-like’ region of the cell which consists of around 80% water . It embodies a variety of different organelles which each perform specific tasks. Also within the cytoplasm is cytosol, where several chemical reactions of metabolism occur. The cytoplasm is the site of glycolysis, in which glycogen stores are broken down to form glucose; this is the initial stage of respiration.
The cell membranes structure is explained through the fluid mosaic model
Figure 2. The structure of the cell membrane Source: