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In a process called transformation    , the cell takes in DNA found in its environment that is shed by other prokaryotes, alive or dead. A pathogen    is an organism that causes a disease. If a nonpathogenic bacterium takes up DNA from a pathogen and incorporates the new DNA in its own chromosome, it too may become pathogenic. In transduction    , bacteriophages, the viruses that infect bacteria, move DNA from one bacterium to another. Archaea have a different set of viruses that infect them and translocate genetic material from one individual to another. During conjugation    , DNA is transferred from one prokaryote to another by means of a pilus that brings the organisms into contact with one another. The DNA transferred is usually a plasmid, but parts of the chromosome can also be moved.

Cycles of binary fission can be very rapid, on the order of minutes for some species. This short generation time coupled with mechanisms of genetic recombination result in the rapid evolution of prokaryotes, allowing them to respond to environmental changes (such as the introduction of an antibiotic) very quickly.

How prokaryotes obtain energy and carbon

Prokaryotes are metabolically diverse organisms. Prokaryotes fill many niches on Earth, including being involved in nutrient cycles such as the nitrogen and carbon cycles, decomposing dead organisms, and growing and multiplying inside living organisms, including humans. Different prokaryotes can use different sources of energy to assemble macromolecules from smaller molecules. Phototrophs obtain their energy from sunlight. Chemotrophs obtain their energy from chemical compounds.

Bacterial diseases in humans

Devastating pathogen-borne diseases and plagues, both viral and bacterial in nature, have affected and continue to affect humans. It is worth noting that all pathogenic prokaryotes are Bacteria; there are no known pathogenic Archaea in humans or any other organism. Pathogenic organisms evolved alongside humans. In the past, the true cause of these diseases was not understood, and some cultures thought that diseases were a spiritual punishment or were mistaken about material causes. Over time, people came to realize that staying apart from afflicted persons, improving sanitation, and properly disposing of the corpses and personal belongings of victims of illness reduced their own chances of getting sick.

Historical perspective

There are records of infectious diseases as far back as 3,000 B.C. A number of significant pandemics caused by Bacteria have been documented over several hundred years. Some of the largest pandemics led to the decline of cities and cultures. Many were zoonoses that appeared with the domestication of animals, as in the case of tuberculosis. A zoonosis is a disease that infects animals but can be transmitted from animals to humans.

Infectious diseases remain among the leading causes of death worldwide. Their impact is less significant in many developed countries, but they are important determiners of mortality in developing countries. The development of antibiotics did much to lessen the mortality rates from bacterial infections, but access to antibiotics is not universal, and the overuse of antibiotics has led to the development of resistant strains of bacteria. Public sanitation efforts that dispose of sewage and provide clean drinking water have done as much or more than medical advances to prevent deaths caused by bacterial infections.

Questions & Answers

what are the characteristics of living things
Ruth Reply
Movement Respiration Nutrition/Feeding Irritability/Sensitivity Growth Excretion Reproduction Deat/Life span
Hashim
What makes children from the same father and mother sometimes don't look alike?
Hashim
identification of problems
Nana Reply
what happens in the process of raising the human arms
Nana
what is biology
Brandi Reply
first step in scientific method
Brandi
In an investigation the pancreatic duct of a mammal was blocked.It was found that the blood sugar regulation remained normal while food digestion was impaired.Explain
Mac Reply
To begin with, obstruction of pancreatic duct will alter the blood sugar level as the juices responsible for glucose regulation will be rendered inconsequential. This will in turn affect the rate of digestion and absorbtion of digested food substances by the Villus .
Muktar
characteristics of algae
OMIME Reply
Algae are eukaryotic organisms. Algae do not have roots and stems. Algae have chlorophyll and helps in carrying out photosynthesis.
Aditi
Cell wall is the rigid layer enclosed by membranes of plants and prokayortic cell, it maintains the shape of the cell and serve as a protective barrier.
chizoba Reply
ECOLOGY: is a branch of biology that studies the interactions among organisms and their biophysical environment, which includes both biotic and abiotic components. 
chizoba
via nutrient cycles and energy flows. For instance, the energy from the sun is captured by plants through photosynthesis. Photosynthesis is a biological process through which plants manufacture their own food with the aid of light from the sun and frc sources (e.g. cabon dioxide and water)
chizoba
What is cell wall
Taiwo Reply
cell wall is the outemost rigid covering of the plants ,that provides protection to the plants.
Aditi
what is ecology, ecosystem?
Nkeng Reply
what is digestive system
Lucky Reply
digestive system is the human syman system that icludes esopuges stomach o braking down of food in to useful substance to our body
samrawit
definition of biology basics
Ritu Reply
the potential energy of a molecule can be inquired by their number of?
Jesus Reply
what is the full meaning of RNA
Ayo Reply
ribose nucleic acid
Nikita
Ribonucleic acid
Jesus
Ribo Nucleic Acid
Aditi
ribonucleic acid
Nana
discuss, describe at least three (3) methods that could be used to improve photosynthesis..
Marvel Reply
Improve the efficiency with which plants capture light Improve the efficiency by which plants turn light into energy The smart canopy concept develop crop planting schemes that increase the penetration of sunlight into lower-level leaves.
Jesus
what is osmosis
Aon Reply
movement of water molecule from higher to lower concentration through a semipereable membrene.
Dr
what of in the case of solute
Aon
osmosis is the movement of molecules from higher concentration region to lower concentration region through semi-permeable membrane.
Broad
in case of solute means that water moves from the region with lower solutes to the region with higher solute. so it is vice versa to water.
Broad
osmosis is the movement of water molecule from a region of lower concentration to a region of higher concentration through a semi permeable membrane
Nana
what are the hydrophilic and hydrophobic region of the plasma membrane?
Samuel Reply
hydrophilic in other word it called water loving and hydrophobic region other word is region that does not contact with water in the plasma membrane.
Broad
the phospholipids
Jesus

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Source:  OpenStax, Concepts of biology. OpenStax CNX. Feb 29, 2016 Download for free at http://cnx.org/content/col11487/1.9
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