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How proteins function? How do proteins work?

By: HWC, Views: 7381

How proteins function is really about how proteins "do work" in cells. How do proteins work? Let's start thinking about protein function by looking at something important to you: your hair. Keratin is a structural protein that is composed of 2 intertwined or helical strands. Keratin is also f...

Dietary Cholesterol & LDL

By: HWC, Views: 7039

LDL comprises 60–70% of total blood lipoproteins and is responsible for carrying cholesterol particles throughout your body. Having a lot of cholesterol carried by LDL lipoproteins is associated with an increased risk of heart disease. In fact, the higher the level, the greater the risk. ...

Pasteur's Experiment

By: HWC, Views: 7103

Louis Pasteur designed a procedure to test whether sterile nutrient broth could spontaneously generate microbial life. To do this, he set up two experiments. In both, Pasteur added nutrient broth to flasks, bent the necks of the flasks into S shapes, and then boiled the broth to kill any existing...

Hershey Chase Experiments

By: HWC, Views: 4885

Hershey and Chase knew that T4 bacteriophages consist of proteins and DNA. They asked which viral component must enter a bacterial cell to infect it: DNA or protein? They grew viruses with either radioactive sulfur, which labels the viral protein, or radioactive phosphorus, which labels DNA. ...

Introduction to Human Immunodeficiency Virus (HIV)

By: Administrator, Views: 10634

Human immunodeficiency virus gains entry into helper T cells, uses the cell DNA to replicate, interferes with normal function of the T cells, and destroys the normal cells. 1 in 10 persons with AIDS: age 50 or older. 4% of all AIDS cases: age 65 or older. AIDS’ main form of treatment: an...

Transcription - Introns and exons

By: HWC, Views: 4807

In most eukaryotic genes, coding regions (exons) are interrupted by noncoding regions (introns). Exon - RNA sequences in the primary transcript that are found in the mRNA. Intron - RNA sequences between exons that are removed by splicing. During transcription, the entire gene is copied ...

Apicomplexan life cycle Animation

By: HWC, Views: 2038

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...

HIV replication/ Replication cycle of HIV

By: HWC, Views: 4905

Replication cycle of HIV, one of the retroviruses. The HIV virus is surrounded by a lipid envelope with embedded proteins. A coat of viral proteins surrounds two strands of RNA and the enzymes used during replication. The virus attaches to and enters the host cell. Viral reverse trans...

Digestive chemicals - types & enzymes

By: HWC, Views: 7706

• Chemical digestion breaks down food as it moves through the digestive tract. • Using enzymes and other digestive chemicals, the process reduces food particles into nutrient molecules that can be absorbed. • Most chemical digestion is done by the actions of digestive enzymes. • O...