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Figure a is an electron micrograph showing a virus on the surface of a bacterial cell. The virus has a large head region, a thick neck and thin spider-like legs attached to the bacterium. Figure b is a drawing that labels the outside of the head as the capsid with the viral genome inside. The neck as the sheath and the legs as tail fibers.
A diagram of a large cell. The outside of the cell is a thin line labeled plasma membrane. A long projection outside of the plasma membrane is labeled flagellum. Shorter projections outside the membrane are labeled cilia. Just under the plasma membrane are lines labeled microtubules and microfilaments. The fluid inside the plasma membrane is labeled cytoplasm. In the cytoplasm are small dots labeled ribosomes. These dots are either floating in the cytoplasm or attached to a webbed membrane labeled rough endoplasmic reticulum. Some regions of the webbed membrane do not have dots; these regions of the membrane are called smooth endoplasmic reticulum. Other structures in the cytoplasm include an oval with a webbed line inside of it; this is labeled the mitochondrion. Spheres in the cytoplasm are labeled peroxisome and lysosome. A pancake stack of membranes is labeled golgi complex. Two short tubes are labeled centrosomes. A large sphere in the cell is labeled nucleus. The outer membrane of this sphere is the nuclear envelope. Holes in the nuclear envelope are called nuclear pores. A smaller sphere in the nucleus is labeled nucleolus.
Table of electron microscopes which use electron beams focused with magnets to produce an image. Magnification: 20 – 100,00× or more. Transmission electron microscopes (TEM) use electron means that pass through a specimen to visual small images; useful to observe small, thin specimens such as tissue sections and subcellular structures. The sample image (Ebola virus) shows a tube shaped into a letter d at one end. Scanning electron microscopes (SEM) use electron beams to visualize surfaces; useful to observe the three-dimensional surface details of specimens. The sample image (Campylobactor jejuni) shows thick three-dimensional spirals.
A diagram of a rod-shaped prokaryotic cell. The thick outer layer is called the capsule, inside of that is a thinner cell wall and inside of that is an even thinner plasma membrane. Inside of the plasma membrane is a fluid called the cytoplasm, little dots called ribosomes, small spheres called inclusions, a small loop of DNA called a plasmid, and a large folded loo of DNA called the nucleoid. Long projections start at the plasma membrane and extend out of the capsule; these are called flagella (singular: flagellum). A shorter projection is labeled pilus. And many very short projections are labeled fimbriae.
A drawing of the plasma membrane. The top of the diagram is labeled outside of cell, the bottom is labeled cytoplasm. Separating these two regions is the membrane which is made of mostly a phospholipid bilayer. Each phospholipid is drawn as a sphere with 2 tails. There are two layers of phospholipids making up the bilayer; each phospholipid layer has the sphere towards the outside of the bilayer and the two tails towards the inside of the bilayer. Embedded within the phospholipid bilayer are a variety of large proteins. Glycolipids have long carbohydrate chains (shown as a chain of hexagons) attached to a single phospholipid; the carbohydrates are always on the outside of the membrane. Glycoproteins have a long carbohydrate chain attached to a protein; the carbohydrates are on the outside of the membrane. The cytoskeleton is shown as a thin layer of line just under the inside of the phospholipid bilayer.
Eggs or gravid proplottidis from an infected individual are passed into the environment; this is the diagnostic stage. Cattle (T. saginata) and pigs (T. solium) become infected by ingesting vegetation contaminated by eggs or gravid proglottids. Oncospheres hatch, penetrating intestinal wall and circulate to musculature. The oncospheres develop into cysticerci in muscles and become infective. Humans are infected by ingesting raw or undercooked infected meat. The scolex attaches to intestine and adults are found in the small intestine.

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About the authors

Senior contributing authors

Nina Parker (Content Lead), Shenandoah University
Dr. Nina Parker received her BS and MS from the University of Michigan, and her PhD in Immunology from Ohio University. She joined Shenandoah University's Department of Biology in 1995 and serves as Associate Professor, teaching general microbiology, medical microbiology, immunology, and epidemiology to biology majors and allied health students. Prior to her academic career, Dr. Parker was trained as a Medical Technologist and received ASCP certification, experiences that drive her ongoing passion for training health professionals and those preparing for clinical laboratory work. Her areas of specialization include infectious disease, immunology, microbial pathogenesis, and medical microbiology. Dr. Parker is also deeply interested in the history of medicine and science, and pursues information about diseases often associated with regional epidemics in Virginia.

Mark Schneegurt (Lead Writer), Wichita State University
Dr. Mark A. Schneegurt is a Professor of Biological Sciences at Wichita State University and maintains joint appointments in Curriculum and Instruction and Biomedical Engineering. Dr. Schneegurt holds degrees from Rensselaer Polytechnic Institute and a Ph.D. from Brown University. He was a postdoctoral fellow at Eli Lilly and has taught and researched at Purdue University and the University of Notre Dame. His research focuses on applied and environmental microbiology, resulting in 70+ scientific publications and 150+ presentations.

Questions & Answers

define metabolism of carbohydrates with example
Thavasi Reply
what is sterilization a
the process of keep equipment free from bacteria
is it only bacteria?
no undesirable fungi and contamination also.
what is streak plate method
what is the biofilm
metabolism is the sum of all the biochemical reaction required for energy generation and use of that energy to synthesize cell materials from small molecules in environment.
what are granulocytes
Shawnitta Reply
granulocytes are type of WBCs which contains granules in the cytoplasm
suitable example for prokaryotes
Suvetha Reply
one of the possible early sources of energy was
uv radiation and lighting
e coli is the example of prokaryotes
archaea too
which is the specific virus causing typhoid
Jeremiah Reply
it's caused by a virulent bacteria called Salmonella Typhi
write the life cycle of HIV
Firomsa Reply
describe the internal and external structure of prokaryotic cell in terms of there appearance and functions
Lenia Reply
compare and contrast similar structures found in prokaryotic and eukaryotic cells
control of microorganisms
what is sterilization
how can a doctor treat a person affected by endospore forming bacteria in his/her wound?
Mambo Reply
define disinfectant
the process of killing
the process of killing microorganisms
a 28 years old woman come to your clinic with complain of fever painful genital blisters which express clear fluid when ruptured burning sensation around the bristers what is the diagnosis?
Ramadhani Reply
genital herpes caused by a virus called herpe simplex virus
what is the reference between selective medium and differential medium?
Tony Reply
the micro flora of air is transient why
Hello.... Am new here
essien Reply
welcome essien
welcome essien
I'm new here
Welcome Macpue!😊
classification of gram positive
lissa Reply
classify gram positive
catalase test is done to differentiate between staph and strep. as staph is catalase positive while strep is catalase negative then staph is differentiate further on coagulase positive and coagulase negative. staph aureus is coagulase positive while staph epidermidis is coagulase negative.
gram positive staph is further differentiated on sensitivity test and manitol salt fermentation test while gram positive strep is differentiated on hemolysis pattern
more about gramm positive
am back any gist
can i use the graph of bacterial growth for my master's thesis?
Christoph Reply
facultative anaerobic bavteria gives uniform turdibity in nutrient broth why?
Princess Reply
oils and waxes are not sterilized in autoclave
what is the function of paraffin
@ MAHI because they can grow all over the media from surface to the bottom as they can utilize oxygen or conduct fermentation in its absence.
2.@MAHI Autoclave uses steam under pressure. The steam cannot penetrate through oil and wax. Thus, dry heat sterilization is preferred than autoclave .
how nutirent agar can converted into blood agar
thank you
take a nutrient agar ........and add 5ml blood and put in it ...........!
nutrient agar +blood 5ml+ distilled water =blood agar .
mixed wellllll
why agar is not a neutrient source?
because it's a general purpose agar only use for growing bacteria
way is antigen
what is antigen
antigen is a foreign body that cause activation of antibody?
Antigen is a toxin or other foreign substance which induces an immune response in the body, especially the production of antibodies.
thanks for that
what is pharmacology
a science that studies about the drug
hello ever one
Work hard
thanks alot
What is the major different between gram positive and gram negative bacteria.
bacteria kya hai
content of their cell wall
koi mujhse basic microbiology ki study k Lea book suggest kro .
Harley prescott
what are the five predisposing factors of opportunistic infections
Asher Reply
1. long term exposure to diseases, that the body immunity weakens.
2. Nature Of some diseases to weaken body immunity such as, AIDS.
3. Use of immuno-suppresive drugs.
anyone... need a hand here 🙋😞
Low immune is the major cause eg for kaposis sarcoma
suitable conditions e.g temp,

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