Search results for: 'develop a vaccine against a bacterium'

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By: HWC, Views: 4861

In the late 1920s, Fred Griffith was attempting to develop a vaccine against a bacterium that causes pneumonia. To find out why two strains of the bacteria differed in their deadliness, he injected mice with four different mixtures. Mice injected with R cells remained healthy. When Griffith ex...

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Embryonic development - Week 4

By: HWC, Views: 7936

• The flat trilaminar embryonic disc undergoes embryonic folding to form a three-dimensional cylinder shaped embryo. • Most organ systems continue, or start, to develop (organogenesis): • The nervous system and chorion continue to develop. • The heart and the rest of the cardiovas...

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Introduction to Autism

By: Administrator, Views: 11094

Autism is a developmental disorder characterized by difficulties with social interaction and communication, and by restricted and repetitive behavior. Parents usually notice signs during the first three years of their child's life. These signs often develop gradually, though some children with au...

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Transferring genes into plants Animation

By: HWC, Views: 5077

Researchers extract DNA from an organism that has a trait they want to introduce into a plant. The genetic donor can be a bacterial cell, a plant cell. or even an animal cell. The desired gene will be transferred into a plasmid, a small circle of bacterial DNA. The gene is cut out of th...

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How antibiotics works? 💊

By: HWC, Views: 7430

The Crisis in Antibiotic Resistance More than 70 years ago, Alexander Fleming discovered penicillin. A few decades later, when this antibiotic was used in World War II, Fleming's discovery had revolutionized medicine. No longer did people have to die from something as trivial as an infected cut.Y...

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Transcription—A molecular view

By: HWC, Views: 3311

Transcription, as related to genomics, is the process of making an RNA copy of a gene's DNA sequence. This copy, called messenger RNA (mRNA), carries the gene's protein information encoded in DNA. During transcription, a DNA molecule is copied into RNA molecules that are then used to translate...

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Immune responses Animation

By: HWC, Views: 4544

Overview of interactions in antibody-mediated and cell-mediated immunity Animation The antibody mediated immune response begins when a naive B cell encounters antigens from a pathogen, such as a bacterium. The B cell binds, processes, and displays this antigen. It is now an antigen-presenti...

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Mycobacterium tuberculosis: Drug Resistance and Natural Selection

By: HWC, Views: 6481

The evolution of drug resistance in microorganisms, such as M. tuberculosis, that cause human diseases is of particular concern to biologists. When Mycobacterium tuberculosis infects the lungs of humans, it causes the disease tuberculosis, also called TB. Once infected, the lungs act as a new...

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Apicomplexan life cycle Animation

By: HWC, Views: 2039

Malaria is caused by the sporozoan, Plasmodium. It is transferred to humans by mosquitoes. When an infected mosquito feeds, infective sporozoites move from her salivary glands into the human body. The bloodstream carries the sporozoites to the liver. Here, they reproduce asexually and...

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