Gonadal dysgenesis and Hypogonadism

Gonadal dysgenesis is the defective embryonic development of the gonads. It is characterized by a progressive loss of primordial germ cells on the developing gonads of an embryo. This leads to extremely hypoplastic (incomplete or arrested development of an organ or a part) and disfunctioning gonads mainly composed of fibrous tissue (streak gonads).

Hypogonadism is a defect of the gonads with retardation of growth, sexual development, and secondary sex characters. It is the inadequate functioning of the gonads as manifested by deficiencies in gametogenesis or the secretion of gonadal hormones.

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Palpation and Palpitation

Palpation is the method of 'feeling' with the hands during a physical examination in which an object is felt to determine its size, shape, firmness, or location.
Palpitation is an awareness of the beating of the heart.

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Bioluminescence Vs Fluorescence

Bioluminescence is light produced by a chemical reaction within an organism. The protein which produces the light is generically called luciferin and the enzyme that catalyzes the reaction is called luciferase. The luciferase catalyzes the oxidation of luciferin resulting in light and an inactive oxyluciferin. In most cases, fresh luciferin must be brought into the system, either through the diet or by internal synthesis.

Sometimes the luciferin and luciferase as well as a co-factor such as oxygen, are bound together to form a single unit called a photoprotein. This molecule can be triggered to produce light when a particular type of ion (frequently Calcium)is added to the system .

Bioluminescence is not the same as "fluorescence" or "phosphorescence". In bioluminescence or chemiluminescence the excitation energy is supplied by a chemical reaction rather than from a source of light.

Fluorescence

In fluorescence, energy from a source of light is absorbed and reemitted as another photon. Fluorescence does not occur in complete darkness.

1. An electron (yellow) "orbits" the nucleus (blue), minding its own business.
2. A source of light of an appropriate wavelength (indicating its energy) strikes.
3. It drives the electron into a higher-energy orbital.
4. The electron is only stable there for a short time.
5. Shortly it returns to the lower energy level.
6. This way it emits the energy as a longer wavelength photon.
7. The electron continues on its way.

Due to energy loss while in the excited state, the photon emitted will always be of longer wavelength (more red, lower energy) than the exciting photon. This is how laundry detergents can get things "whiter than white": by absorbing non-visible UV light and fluorescing in the visible spectrum.

Phosphorescence

Phosphorescence is similar to fluorescence except that the excited product is more stable, so that the time until the energy is released is much longer, resulting in a glow after the light has been removed. This is the basis behind glow-in-the-dark stickers.

Chemiluminescence

Chemiluminescence is a general term for production of light when the excitation energy has come from a chemical reaction (as opposed to the absorption of photons, in fluorescence).

Bioluminescence is a subset of chemiluminescence, where the light-producing chemical reaction occurs inside an organism.

Types of Luciferens

There are few basic luciferins (light emitters).

Bacterial Luciferin 

Dinoflagellate luciferin

Vargulin or Cypridina-type luciferin

Coelenterazine

Firefly luciferin

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What is the difference between albumin and albumen?

Albumin ia a class of simple, water-soluble proteins that can be coagulated by heat and are found in egg white, blood serum, milk, and many other animal and plant tissues.
Albumen  is the white of an egg which consists of several dozen types of albumin, mostly ovalbumin.

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