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Results for: 'MS'

How does asthma work?And How do you treat asthma?

By: HWC, Views: 5608

These are the parts of the respiratory system. Sinuses and Nasal Passages Mouth Windpipe (Trachea) Lungs Airways (Bronchial Tubes) Airsacs (Alveoli) When we breathe, air moves easily in and out of the lungs. The small airways are also called bronchial tubes. The side of the tube is...

Calvin Cycle Explained!

By: HWC, Views: 6361

he light-independent reactions make sugars by way of a cyclic pathway called the Calvin cycle. The cycle begins when rubisco attaches a carbon from carbon dioxide to ribulose bisphosphate. The molecule that forms splits into two molecules of PGA. Each PGA gets a phosphate group from ATP a...

Mycobacterium tuberculosis: Drug Resistance and Natural Selection

By: HWC, Views: 5450

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...

Brief Summary on Photosynthesis - Animation

By: HWC, Views: 5660

Can increase its weight by 150 pounds as it grows. Where does the new tissue come from? From the soil? From water? Or possibly from the air? The amazing truth is that new material. comes from an invisible gas in the air. In the process of photosynthesis, plants capture carbon dioxide ga...

Gastrulation: cross section of the frog

By: HWC, Views: 5741

Gastrulation Most animals enter a phase early in development called gastrulation. In this phase, a tiny ball or disc of cells rearranges to form three embryonic layers of tissue, called germ layers. The germ layers of the embryo—now called a gastrula—are called the endoderm, mesoderm, and eco...

What are the Parts of a Plant Cell?

By: HWC, Views: 5705

Every chloroplast in a plant cell is packed with stacks of flattened sacs called thylakoids. The thylakoid membranes contain chlorophyll, as well as most of the other components required for the light reactions of photosynthesis. The chlorophyll-containing structures within the membranes are c...

Hydrogen bonds vs. Ionic bond

By: HWC, Views: 5473

The slight positive charge of a hydrogen atom in a water molecule can attract an atom with a slight negative charge, such as the nitrogen in a molecule of ammonia. This forms a hydrogen bond between the two atoms. Hydrogen bonds join the two strands of a DNA molecule. Although hydrogen bo...

Phases of mitosis

By: HWC, Views: 4645

Prophase is the first step in the mitotic process. During prophase, the chromosomes condense. The centrosomes begin to form a spindle and move into position on opposite sides of the cell. Sister chromatids are held together by a protein called cohesin at the centromere. Prometaphase is the sec...

Mendel's pea plant, Pisum sativum experimental

By: HWC, Views: 4531

Mendel chose the garden pea plant, Pisum sativum, for experimental tests of his ideas about inheritance. Under normal circumstances, the garden pea plant is self-fertilizing. This cross-section shows the gamete-forming structures. Sperm-producing pollen grains form in the stamens. Eggs deve...

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