Search results for: 'ionic%20bond'

Watch Later 1:32

By: HWC, Views: 5449

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...

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Ionic bonds - role of ions in the body

By: HWC, Views: 6861

Ions • Atoms fill up the outer orbital by transferring electrons from one atom to another. • Atoms now bear a charge and are called ions. • Sodium ion, losing an electron, has a +1 charge. • Chlorine ion, gaining an electron, has a -1 charge. Formation • An ionic bond is t...

Watch Later 1:23

Bond types - Atomic structure and basis of bonds

By: HWC, Views: 7020

• Chemical bonds are fundamental to the structure and function of many types of molecules, such as proteins, carbohydrates, lipids, nucleic acids, gases, salts and water. ■ These molecules are composed of atoms that are held together by three different types of bonds. • The three types ...

Watch Later 2:59

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

By: HWC, Views: 3964

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...

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Primary Active Transport - electrochemical gradient and ion transport / water movement

By: HWC, Views: 6753

Energy derived from ATP changes the shape of a transporter protein which pumps a substance across a plasma membrane against its concentration gradient An electrochemical gradient is a gradient of electrochemical potential, usually for an ion that can move across a membrane. The gradient consis...

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Neurotransmission at chemical synapses & Excitory and inhibitory potentials

By: HWC, Views: 6553

• A series of events occur at chemical synapses in order to communicate with the adjacent cell. • The action potential arrives at the presynaptic membrane. • The depolarization phase of the action potential opens voltage gated Ca+ channels. • increased inflow of Ca+' into the cyto...

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How do the different types of chromatography work? (No Audio)

By: HWC, Views: 5965

Chromatography is a term for a variety of techniques in which a mixture of dissolved components is fractionated as it moves through some type of porous matrix. A glass column is filled with beads of an inert matrix. The mixture of proteins to be purified is dissolved in a solution and passed ...

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Protein Structure - Primary, Secondary, Tertiary and Quaternary

By: HWC, Views: 6629

A protein's first order structure, or primary structure, begins with the amino acid sequence of the polypeptide chain. The 20 different amino acids can be arranged in an infinite number of sequences. For example, the hormone insulin, which regulates the uptake of glucose from the blood into ce...

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Covalent bonds - role in the body

By: HWC, Views: 6636

A covalent bond is formed when atoms share one or more pairs of electrons. This is opposed to an ionic bond, where electrons are actually transferred from one atom to another. Formation • Atoms fill up the outer orbital by sharing electrons. • Two oxygen atoms sharing electrons form on...

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