<< Chapter < Page Chapter >> Page >
a) A small diagram of the cell highlighting the nucleus and endoplasmic reticulum. The nucleus is a large sphere in the cell and the endoplasmic reticulum is a series of webbed membranes just outside the nucleus. B) A micrograph showing these same structures. Outside the nuclear envelope are many lines labeled rough endoplasmic reticulum. A smaller set of lines is labeled mitochondrion overlaying part of the RER.
The rough endoplasmic reticulum is studded with ribosomes for the synthesis of membrane proteins (which give it its rough appearance).

Golgi apparatus

The Golgi apparatus was discovered within the endomembrane system in 1898 by Italian scientist Camillo Golgi (1843–1926), who developed a novel staining technique that showed stacked membrane structures within the cells of Plasmodium , the causative agent of malaria. The Golgi apparatus is composed of a series of membranous disks called dictyosomes, each having a single lipid bilayer, that are stacked together ( [link] ).

Enzymes in the Golgi apparatus modify lipids and proteins transported from the ER to the Golgi, often adding carbohydrate components to them, producing glycolipids, glycoproteins, or proteoglycans. Glycolipids and glycoproteins are often inserted into the plasma membrane and are important for signal recognition by other cells or infectious particles. Different types of cells can be distinguished from one another by the structure and arrangement of the glycolipids and glycoproteins contained in their plasma membranes. These glycolipids and glycoproteins commonly also serve as cell surface receptors.

Transport vesicles leaving the ER fuse with a Golgi apparatus on its receiving, or cis , face. The proteins are processed within the Golgi apparatus, and then additional transport vesicles containing the modified proteins and lipids pinch off from the Golgi apparatus on its outgoing, or trans , face. These outgoing vesicles move to and fuse with the plasma membrane or the membrane of other organelles.

Exocytosis is the process by which secretory vesicles (spherical membranous sacs) release their contents to the cell’s exterior ( [link] ). All cells have constitutive secretory pathways in which secretory vesicles transport soluble proteins that are released from the cell continually (constitutively). Certain specialized cells also have regulated secretory pathways , which are used to store soluble proteins in secretory vesicles. Regulated secretion involves substances that are only released in response to certain events or signals. For example, certain cells of the human immune system (e.g., mast cells) secrete histamine in response to the presence of foreign objects or pathogens in the body. Histamine is a compound that triggers various mechanisms used by the immune system to eliminate pathogens.

A small diagram of the cell outlining the Golgi complex which is a series of stacked membranes in the cell. A more detailed diagram shows the stacked membranes labeled cisternae and the inner regions of the stacks labeled lumen. Small spheres on the top are show transport vesicles from ER fuse with the cis face of the golgi. Small spheres on the bottom show newly formed secretory vesicles emerging from the trans face of the golgi. A micrograph shows the golgi in the cell as a stack of lines forming a semi-circle.
A transmission electron micrograph (left) of a Golgi apparatus in a white blood cell. The illustration (right) shows the cup-shaped, stacked disks and several transport vesicles. The Golgi apparatus modifies lipids and proteins, producing glycolipids and glycoproteins, respectively, which are commonly inserted into the plasma membrane.

Lysosomes

In the 1960s, Belgian scientist Christian de Duve (1917–2013) discovered lysosomes , membrane-bound organelles of the endomembrane system that contain digestive enzymes. Certain types of eukaryotic cells use lysosomes to break down various particles, such as food, damaged organelles or cellular debris, microorganisms, or immune complexes. Compartmentalization of the digestive enzymes within the lysosome allows the cell to efficiently digest matter without harming the cytoplasmic components of the cell.

Questions & Answers

please what is the topic today.
Anafure Reply
I hope u are doing good
Anafure
Yes ooo u
Daniel
what is immunoglobulin specifications
hop Reply
what if she is having stomach pain ND also running temprature
Samuel Reply
i wante to study medicine in university so how i should prepare my self
Lissa Reply
microorganism functions
NUHU Reply
how does the helicobacteri pylori affect the stomach walls?
Erick Reply
hi
Allan
Hlo
SUMIT
hi
Umar
hi
Umar
when the stomach is been affected with helicobacteria what are the preventive measure to be considered to ensure specific outcome?
Umar
yeah
Ayan
proper alimentation( feed properly),avoid eating lot of pepper but the main point is nutrition if you feed well the bacteria won't cause digestion of the stomach wall and thus you will be fine
Nanjoh
what is microbiology
vijay Reply
microbiology is the scientific study of microorganisms .microorganisms are those organisms that are too small to see with the naked eye ex-bacteria fungi
Yashkin
a branch of biological science concerned with organisms that can not be observed with a naked eye
Mooya
what are the types of granulocytes and explain
lord
polymorpho nuclear leukocyte, known as granulocyte are divide into three,1-polymorpho eosinophil 2-polymorpho basophil 3-polymorpho neutrophil
Musa
microbiology is scientific study of microorganism which can nt be seen by naked eye,for example bacteria,viruses, protozoa ad fungi.
Emma
microbiology is the scientific study of microorganisms
Atia
good
Samuel
microbiology is the study of micro organisms by the use of microscope to know how they react and respire to it environments
Daniel
microbiology is a branch of science which studies microbe
Ivy
microbiology is the study of microoganism
paul
microbiology is the study of tiny organisms which are difficult to be seen by naked eyes
hop
I want to know more about sample collection on the field
Ama Reply
blood collection and urinarysis
Lizzy
2143
Lizzy
yes
Lizzy
In the periodic table the number on the upper left hand side is what
Aurelia Reply
Hydrogen
Tob
am not talking about the elements
Aurelia
Is it the atomic number or the mass number
Aurelia
hologen
Usman
differences between acid fast and non acid fast bacilli
ANTHONY Reply
acid fast have cell wall that holds to carbol fuschin stain while non acid fast doesn't have. it readily releases out the primary stain the carbol fuschin.
LAFIA
where do I post a question that isn't related to that topic
eklectc
hi everyone
kennedy
hello
Olivia
for sure, this question is not related to the topic.
LAFIA
can someone explain the process of glycolysis and the electron transport chain? I'm so freakin lost. it loses carbons, gains hydroxyls, gains, loses Hydrogens....ugh it's like a foreign language to me! or direct me to a youTube video or something that will make this seem easier to concept?
eklectc
it's a loaded question, sorry!
eklectc
why is DNA a genetic material
Mcbeth Reply
DNA is genetic material because it contains chromosome contains the traits which includes characters and behavioral characteristics
chima
why is it difficulty to classfy protista
Tanaka
Good
Eddy
what is infection prevention
Muhammed Reply
good hygiene
Dhaqan
way of preventing disease causing germs
henry
maintenance of sterilization
Pooja
h
Faustina
describe the components of the epidemiology triangle
Muhammed Reply
Hai
Nantongo
hii
Md
where from you
Md
i am Indian
Md
you
Md
Hello friend
effiong
How are you people doing
effiong
أ‌) Host factor ب) pathogen ج) environment
Widad
Hello
Kofi
Hi
Widad
hey hi
kalai
The epidemiologic triangle is made up of three parts: agent, host and environment
Princess
please can a microbiologist will work at hospital
Usman
yes but some state whose have deficiency of medical laboratories practictioners
jamilu
yes, as a lab scientists
kehinde
what are the fluids used in biochemistry Lab used to diagnose diseases
Jb Reply
fadumo qule a gemil3
fadumo Reply
Faadum mahamud disease micro biology
fadumo
makuway diinkaraan suaalo
fadumo

Get the best Microbiology course in your pocket!





Source:  OpenStax, Microbiology. OpenStax CNX. Nov 01, 2016 Download for free at http://cnx.org/content/col12087/1.4
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Microbiology' conversation and receive update notifications?

Ask