E-Portfolio BMY3101 - Week 6

Greetings!

So for this week we learned on the external structures of prokaryotes. Basically there are several parts of external structures in prokaryotes which are :

1. Glycocalyx - highly-hydrated fibrous meshwork of carbohydrates that projects out and covers the membrane of endothelial cells to mediatescell attachment, retains humidity during exposure to dry environments, protects against molecular and cellular antibacterial agents (antibiotics, surfactants, bacteriophages, phagocytes) and other vital functions

2. Flagella -  long, hairlike organelles that extend from the cell, permitting it to move. In prokaryotic cells, such as bacteria, the flagella rotate like the propeller of a motorboat

3. Axial filaments - a filament that wraps around the cell and makes the cell move in a cork screw movement. It composed of endoflagella that spiral around the cells instead of towards the surrounding meduim

4. Cell wall - Bacteria are divided into two major groups: gram-positive and gram-negative, based on their reaction to gram staining. Note that all gram-positive bacteria belong to one phylum; bacteria in the other phyla (Proteobacteria, Chlamydias, Spirochetes, Cyanobacteria, and others) are gram-negative. The gram-staining method is named after its inventor, Danish scientist Hans Christian Gram (1853–1938). The different bacterial responses to the staining procedure are ultimately due to cell wall structure. Gram-positive organisms typically lack the outer membrane found in gram-negative organisms.