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Anatomy and Chemical Makeup of a Single Hair (Animation)

By: HWC, Views: 4906

The hair's outer cuticle surrounds hair cells filled with tough keratin macrofibrils. Each macrofibril consists of smaller microfibrils. A microfibril is made up of three keratin polypeptide chains. The chains are linked together by disulfide bonds. A hair consists of keratin chains held...

A timeline of the teeth (Explained - No Audio)

By: HWC, Views: 5586

Although most babies don't appear to have any teeth when they are born, they are in fact already well developed out of sight beneath the gum. The first molars erupt at about 12-14 months. The canines follow at about 16-18 months . By 3 years old, the second molars have usually erupted, c...

Kidney Stones

By: Administrator, Views: 9439

Kidney stones (renal lithiasis, nephrolithiasis) are hard deposits made of minerals and salts that form inside your kidneys. Kidney stones have many causes and can affect any part of your urinary tract — from your kidneys to your bladder. Often, stones form when the urine becomes concentrate...

Mutations and translation

By: HWC, Views: 3180

A mutation, which may arise during replication and/or recombination, is a permanent change in the nucleotide sequence of DNA. Damaged DNA can be mutated either by substitution, deletion or insertion of base pairs. Mutations, for the most part, are harmless except when they lead to cell death or t...

Nerve Type Animation (Part 1)

By: Administrator, Views: 289

Used to describe neuronal processes conducting impulses from one location to another. Nerve fibers: - Nerve fibers of the PNS are wrapped by protective membranes called sheaths. - Myelinated fibers have an inner sheath of myelin, a thick fatty substance, and an outer sheath or neurilemma compo...

Nerve Type Animation (Part 2)

By: Administrator, Views: 271

Used to describe neuronal processes conducting impulses from one location to another. Nerve fibers: - Nerve fibers of the PNS are wrapped by protective membranes called sheaths. - Myelinated fibers have an inner sheath of myelin, a thick fatty substance, and an outer sheath or neurilemma compo...

Multiple Sclerosis Animation

By: Administrator, Views: 9890

Multiple sclerosis (MS) is a demyelinating disease in which the insulating covers of nerve cells in the brain and spinal cord are damaged. This damage disrupts the ability of parts of the nervous system to communicate, resulting in a range of signs and symptoms, including physical, mental, and so...

Deafness Culture

By: Administrator, Views: 9810

Deaf culture is the set of social beliefs, behaviors, art, literary traditions, history, values, and shared institutions of communities that are influenced by deafness and which use sign languages as the main means of communication. When used as a cultural label especially within the culture, the...