Search results for: 'Molecules and Membrane'

Watch Later 0:34

By: Administrator, Views: 11226

Dendrites (from Greek δένδρον déndron, "tree"), also dendrons, are branched protoplasmic extensions of a nerve cell that propagate the electrochemical stimulation received from other neural cells to the cell body, or soma, of the neuron from which the dendrites project. Electrical stimula...

Watch Later 2:59

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

By: HWC, Views: 5080

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...

Watch Later 2:35

Contraction cycle of a sarcomere

By: HWC, Views: 8200

• A single nervous signal releases Ca2+ ions into the sarcoplasm and initiates the contraction cycle. step 1. ATP hydrolysis • ATP provides the to move myosin molecules back into the energized configuration necessary to perform the power stroke. Step 2. Crossbridge attachment • Myosin...

Watch Later 1:27

Hydrogen bonds - role in the body

By: HWC, Views: 8037

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. ...

Watch Later 0:42

Type of Transport - Active and Passive Processes

By: HWC, Views: 7968

Active transport moves materials from lower to a higher concentration, while passive transport moves materials from higher to lower concentration. Active transport requires energy to proceed, while passive transport does not require the input of extra energy to occur. Transport processes that ...

Watch Later 0:31

Epidural Hematoma

By: Administrator, Views: 10523

Epidural hematoma is when bleeding occurs between the tough outer membrane covering the brain (dura mater) and the skull. Often there is loss of consciousness following a head injury, a brief regaining of consciousness, and then loss of consciousness again. Other symptoms may include headache, co...

Watch Later 1:20

Miller's reaction chamber experiment Animation

By: HWC, Views: 1322

A simple diagram of Stanley Miller and Harold Urey's experimental apparatus. The lower portion of the apparatus was filled with water. The upper portion was filled with a mixture of gases that simulated the earth's early atmosphere. Examples are methane, ammonia, hydrogen and carbon dioxide. ...

Watch Later 1:53

Lipid catabolism ( ketogenesis and oxidation of glycerol) and Lipid anabolism (lipogenesis)

By: HWC, Views: 8049

• During excessive beta oxidation, the two-carbon fatty acid fragments are converted into acidic ketone bodies. • Ketosis, the overproduction of ketone bodies, can lead to acidosis (ketoacidosis) of the blood. • After lipolysis, glycerol is converted to pyruvic acid. • Pyruvic aci...

Watch Later 2:14

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

By: HWC, Views: 7069

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 ...

Search Results