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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

Three charges q_{1}=+3\mu C, q_{2}=+6\mu C and q_{3}=+8\mu C are located at (2,0)m (0,0)m and (0,3) coordinates respectively. Find the magnitude and direction acted upon q_{2} by the two other charges.Draw the correct graphical illustration of the problem above showing the direction of all forces.
Kate Reply
To solve this problem, we need to first find the net force acting on charge q_{2}. The magnitude of the force exerted by q_{1} on q_{2} is given by F=\frac{kq_{1}q_{2}}{r^{2}} where k is the Coulomb constant, q_{1} and q_{2} are the charges of the particles, and r is the distance between them.
Muhammed
What is the direction and net electric force on q_{1}= 5µC located at (0,4)r due to charges q_{2}=7mu located at (0,0)m and q_{3}=3\mu C located at (4,0)m?
Kate Reply
what is the change in momentum of a body?
Eunice Reply
what is a capacitor?
Raymond Reply
Capacitor is a separation of opposite charges using an insulator of very small dimension between them. Capacitor is used for allowing an AC (alternating current) to pass while a DC (direct current) is blocked.
Gautam
A motor travelling at 72km/m on sighting a stop sign applying the breaks such that under constant deaccelerate in the meters of 50 metres what is the magnitude of the accelerate
Maria Reply
please solve
Sharon
8m/s²
Aishat
What is Thermodynamics
Muordit
velocity can be 72 km/h in question. 72 km/h=20 m/s, v^2=2.a.x , 20^2=2.a.50, a=4 m/s^2.
Mehmet
A boat travels due east at a speed of 40meter per seconds across a river flowing due south at 30meter per seconds. what is the resultant speed of the boat
Saheed Reply
50 m/s due south east
Someone
which has a higher temperature, 1cup of boiling water or 1teapot of boiling water which can transfer more heat 1cup of boiling water or 1 teapot of boiling water explain your . answer
Ramon Reply
I believe temperature being an intensive property does not change for any amount of boiling water whereas heat being an extensive property changes with amount/size of the system.
Someone
Scratch that
Someone
temperature for any amount of water to boil at ntp is 100⁰C (it is a state function and and intensive property) and it depends both will give same amount of heat because the surface available for heat transfer is greater in case of the kettle as well as the heat stored in it but if you talk.....
Someone
about the amount of heat stored in the system then in that case since the mass of water in the kettle is greater so more energy is required to raise the temperature b/c more molecules of water are present in the kettle
Someone
definitely of physics
Haryormhidey Reply
how many start and codon
Esrael Reply
what is field
Felix Reply
physics, biology and chemistry this is my Field
ALIYU
field is a region of space under the influence of some physical properties
Collete
what is ogarnic chemistry
WISDOM Reply
determine the slope giving that 3y+ 2x-14=0
WISDOM
Another formula for Acceleration
Belty Reply
a=v/t. a=f/m a
IHUMA
innocent
Adah
pratica A on solution of hydro chloric acid,B is a solution containing 0.5000 mole ofsodium chlorid per dm³,put A in the burret and titrate 20.00 or 25.00cm³ portion of B using melting orange as the indicator. record the deside of your burret tabulate the burret reading and calculate the average volume of acid used?
Nassze Reply
how do lnternal energy measures
Esrael
Two bodies attract each other electrically. Do they both have to be charged? Answer the same question if the bodies repel one another.
JALLAH Reply
No. According to Isac Newtons law. this two bodies maybe you and the wall beside you. Attracting depends on the mass och each body and distance between them.
Dlovan
Are you really asking if two bodies have to be charged to be influenced by Coulombs Law?
Robert
like charges repel while unlike charges atttact
Raymond
What is specific heat capacity
Destiny Reply
Specific heat capacity is a measure of the amount of energy required to raise the temperature of a substance by one degree Celsius (or Kelvin). It is measured in Joules per kilogram per degree Celsius (J/kg°C).
AI-Robot
specific heat capacity is the amount of energy needed to raise the temperature of a substance by one degree Celsius or kelvin
ROKEEB
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Source:  OpenStax, Microbiology. OpenStax CNX. Nov 01, 2016 Download for free at http://cnx.org/content/col12087/1.4
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