Search results for: 'red blood cells'

Watch Later 0:53

By: Administrator, Views: 367

As soon as your baby is born, a delivery nurse will set one timer for one minute and another for five minutes. When each of these time periods is up, a nurse or physician will give your baby her first "tests," called Apgars. This scoring system (named after its creator, Virginia Apgar) helps t...

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Hershey Chase Experiments

By: HWC, Views: 4902

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. ...

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The pH scale - Strong acids and Weak acids

By: HWC, Views: 7775

The pH scale • Expresses concentration of H+. • range: 0-14. • 7 is neutral. • Less 7 is acid. • greater 7 is basic (alkaline). Strong acids - role in the body ■ In strong acids all molecules dissociate. ■ HC1 is highly acidic and found only in the stomach. • H...

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Oxygen transport: association and dissociation & Factors that affect hemoglobin's saturation with O2

By: HWC, Views: 7689

• The production of oxyhemoglobin can be illustrated through the following reaction: 02 + Hb-H --) Hb-02 + H+ • This equation represents the binding of oxygen to the iron ions in heme groups in hemoglobin molecules. • Oxygen binding or loading occurs at the lungs • The dissociatio...

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Structures that affect circulation - venous return

By: HWC, Views: 7582

• Venous return directly affects cardiac output. • Increased venous return leads directly to greater cardiac output whereas decreased return contributes to decreased output. • Venous return depends on: • Blood volume regulation by the kidneys. • Venous tone. • Skeletal muscl...

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Heart sounds

By: HWC, Views: 7621

During a normal, healthy heartbeat, or what we call a cardiac cycle, the top two chambers of the heart, called the atria, contract simultaneously. Then, as they relax, the bottom two chambers, called the ventricles, contract. This explains what happens during a cardiac cycle, but what it doesn't ...

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DNA Replication

By: HWC, Views: 4607

DNA replication is the process by which a double-stranded DNA molecule is copied to produce two identical DNA molecules. Replication is an essential process because, whenever a cell divides, the two new daughter cells must contain the same genetic information, or DNA, as the parent cell.

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Origin of organelles Animation

By: HWC, Views: 1386

Possible origins of the nucleus and other organelles. Some prokaryotic cells have infoldings of their plasma membrane. These infoldings may have served as channels from the cytoplasm to the cell surface. These membranous folds may have evolved into the endoplasmic reticulum and the nuclear e...

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Plant Defense Mechanisms from Pathogens

By: HWC, Views: 7195

Plants and pathogens have coevolved such that pathogens can recognize plants by the sugars, or other molecules, they produce. Plants, in turn, can recognize pathogens by the molecules they produce. The ability to recognize pathogens allows plants to activate defense systems that can prevent wides...

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