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Bond in biological molecules (Ionic, Covalent and Hydrogen bonds)/ How atoms bond?

By: HWC, Views: 3990

Sodium atoms and chloride atoms have unfilled orbitals in their outer shells. The lone electron in the outermost shell of a sodium atom can be pulled or knocked out. This ionizes the atom. It is now a positively charged sodium ion. A chlorine atom has an electron vacancy in its outer shell and...

Hydrogen bonds - role in the body

By: HWC, Views: 7020

A hydrogen bond is the electromagnetic attraction between polar molecules in which hydrogen is bound to a larger atom, such as oxygen or nitrogen. This is not a sharing of electrons, as in a covalent bond. Instead, this is an attraction between the positive and negative poles of charged atoms. ...

What are the Parts of a Plant Cell?

By: HWC, Views: 5698

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...

Major Elements in Biological Molecules: Lipids

By: HWC, Views: 5921

A triglyceride (also called triacylglycerol) is composed of three fatty acid molecules and one glycerol molecule. The fatty acids attach to the glycerol molecule by a covalent ester bond. The long hydrocarbon chain of each fatty acid makes the triglyceride molecule nonpolar and hydrophobic. Pa...

Properties of water -structure of water and polarity (Ionized and polar compounds)

By: HWC, Views: 6827

■ Water transports most of the molecules in the body. ■ The structure of a water molecule allows it to dissolve other molecules. ■ Shared electrons spend more time near the oxygen atom. ■ Oxygen end has a partial negative charge. ■ Hydrogen ends have a partial positive charge....

Sister chromatids of a metaphase chromosome animation

By: HWC, Views: 4717

At metaphase, the chromosomes are duplicated and are at their most condensed. In each chromosome. two identical sister chromatids are held together at a constricted region called the centromere. When a chromosome is condensed, interactions among chromosomal proteins keep loops of DNA tightly ...

Glycolysis - Introduction to ATP and the burning of sugar

By: HWC, Views: 6749

Do you use sugar with your coffee or tea? Or do you occasionally drink a sport or soft drink? As millions of people do each day, they obtain energy from the sugar added or contained in these drinks. How can we understand this concept of energy within a sugar molecule? Let's take a tablespoon ...

Energy sources - types

By: HWC, Views: 6890

• The amount of ATP stored in a skeletal muscle cell can only provide muscular activity for two to three seconds. • Muscle cells must be able to generate additional molecules of ATP to continue contracting. • Muscle cells can generate ATP from several processes: • Phosphogen syste...

Non-polar compounds - insolubility

By: HWC, Views: 6694

• A non-polar molecule has uniform distribution of electrons. • Non-polar compounds like fatty acids in lipids have a high proportion of carbon and hydrogen. • Lipids possess no charge or partial charge. • Lipids are not attracted to water molecules. • Lipids are not soluble in...