CSS Forums - Notes for Zoology

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mashallah! u have a gr8 job......have u done masters in zoology?.....or its ur kind effort at ur own for css?

[quote=prissygirl]mashallah! u have a gr8 job......have u done masters in zoology?.....or its ur kind effort at ur own for css?[/quote]

Salam
yes i have done masters in zoology :D and M phil in zoology;) .this is for those who want to opt zoology:closedeye for css.
thanks and regards

Invertebrate Short Notes

[CENTER][B][SIZE=4]Spicules[/SIZE][/B][/CENTER]
[SIZE=3][FONT=Times New Roman][B][COLOR=black]Spicules[/COLOR][/B][COLOR=black] are tiny spike-like structures of diverse origin and function found in many organisms, such as the [URL="http://www.cssforum.com.pk/wiki/Copulation"][COLOR=black]copulatory[/COLOR][/URL] spicules of certain [URL="http://www.cssforum.com.pk/wiki/Roundworm"][COLOR=black]nematodes[/COLOR][/URL] or the grains on the skin of some [URL="http://www.cssforum.com.pk/wiki/Frog"][COLOR=black]frogs[/COLOR][/URL].[/COLOR][/FONT][/SIZE]

[COLOR=black][FONT=Times New Roman][SIZE=3]This article discusses the [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Skeleton"][COLOR=black][FONT=Times New Roman][SIZE=3]skeletal[/SIZE][/FONT][/COLOR][/URL][FONT=Times New Roman][SIZE=3] spicules that occur in most [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Sea_sponge"][COLOR=black][FONT=Times New Roman][SIZE=3]sponges[/SIZE][/FONT][/COLOR][/URL][FONT=Times New Roman][SIZE=3]. They provide structural support and deter [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Predator"][COLOR=black][FONT=Times New Roman][SIZE=3]predators[/SIZE][/FONT][/COLOR][/URL][SIZE=3][FONT=Times New Roman]. Large spicules, visible to the naked eye are referred to as [B]megascleres[/B], while smaller, microscopic ones are termed [B]microscleres[/B].[/FONT][/SIZE][/COLOR]
[COLOR=black][FONT=Times New Roman][SIZE=3]Spicules have four major symmetry types: Monaxon (simple cylinders with pointed ends), triaxon, tetraxon, and polyaxon. Sponges can be [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Calcium_carbonate"][COLOR=black][FONT=Times New Roman][SIZE=3]calcareous[/SIZE][/FONT][/COLOR][/URL][FONT=Times New Roman][SIZE=3], [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Biogenic_silica"][COLOR=black][FONT=Times New Roman][SIZE=3]siliceous[/SIZE][/FONT][/COLOR][/URL][FONT=Times New Roman][SIZE=3], or composed of [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Spongin"][COLOR=black][FONT=Times New Roman][SIZE=3]spongin[/SIZE][/FONT][/COLOR][/URL][FONT=Times New Roman][SIZE=3]. The meshing of many spicules serves as the sponge’s [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Skeleton"][COLOR=black][FONT=Times New Roman][SIZE=3]skeleton[/SIZE][/FONT][/COLOR][/URL][FONT=Times New Roman][SIZE=3]. The composition, size, and shape of spicules is one of the largest determining factors in sponge [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Taxonomy"][COLOR=black][FONT=Times New Roman][SIZE=3]taxonomy[/SIZE][/FONT][/COLOR][/URL][SIZE=3][FONT=Times New Roman].[/FONT][/SIZE][/COLOR]
[COLOR=black][FONT=Times New Roman][SIZE=3]Spicules are formed by [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Sclerocyte"][COLOR=black][FONT=Times New Roman][SIZE=3]sclerocytes[/SIZE][/FONT][/COLOR][/URL][FONT=Times New Roman][SIZE=3], which are derived from archaeocytes. The sclerocyte begins with an organic [/SIZE][/FONT][URL="http://en.wiktionary.org/wiki/Filament"][COLOR=black][FONT=Times New Roman][SIZE=3]filament[/SIZE][/FONT][/COLOR][/URL][FONT=Times New Roman][SIZE=3], and adds silica to it. Spicules are generally elongated at a rate of 1-10 μm per hour. Once the spicule reaches a certain length it protrudes from the sclerocyte [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Cell_(biology)"][COLOR=black][FONT=Times New Roman][SIZE=3]cell[/SIZE][/FONT][/COLOR][/URL][FONT=Times New Roman][SIZE=3] body, but remains within the cell’s [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Cell_membrane"][COLOR=black][FONT=Times New Roman][SIZE=3]membrane[/SIZE][/FONT][/COLOR][/URL][SIZE=3][FONT=Times New Roman]. On occasion, sclerocytes may begin a second spicule while the first is still in progress.[/FONT][/SIZE][/COLOR]
[LEFT][COLOR=black][FONT=Times New Roman][SIZE=3]Research on the [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Venus%27_Flower_Basket"][SIZE=3][FONT=Times New Roman][I][COLOR=black]Euplectella aspergillum[/COLOR][/I][COLOR=black] (Venus' Flower Basket)[/COLOR][/FONT][/SIZE][/URL][FONT=Times New Roman][SIZE=3] demonstrated that the spicules of certain deep-sea sponges have similar traits to [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Optical_fibre"][COLOR=black][FONT=Times New Roman][SIZE=3]Optical fibre[/SIZE][/FONT][/COLOR][/URL][FONT=Times New Roman][SIZE=3]. In addition to being able to trap and transport light, these spicules have a number of advantages over commercial fibre optic wire. They are stronger, resist stress easier, and form their own support elements. Also, the low-temperature formation of the spicules, as compared to the high temperature stretching process of commercial fibre optics, allows for the addition of [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Impurity"][COLOR=black][FONT=Times New Roman][SIZE=3]impurities[/SIZE][/FONT][/COLOR][/URL][FONT=Times New Roman][SIZE=3] which improve the [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Refractive_index"][COLOR=black][FONT=Times New Roman][SIZE=3]refractive index[/SIZE][/FONT][/COLOR][/URL][FONT=Times New Roman][SIZE=3]. In addition, these spicules have built-in [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Lens_(optics)"][COLOR=black][FONT=Times New Roman][SIZE=3]lenses[/SIZE][/FONT][/COLOR][/URL][FONT=Times New Roman][SIZE=3] in the ends which gather and focus light in dark conditions. It has been theorized that this ability may function as a light source for [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Symbiosis"][COLOR=black][FONT=Times New Roman][SIZE=3]symbiotic[/SIZE][/FONT][/COLOR][/URL][URL="http://www.cssforum.com.pk/wiki/Algae"][COLOR=black][FONT=Times New Roman][SIZE=3]algae[/SIZE][/FONT][/COLOR][/URL][FONT=Times New Roman][SIZE=3] (as with [I]Rosella racovitzae[/I]) or as an attractor for [/SIZE][/FONT][URL="http://www.cssforum.com.pk/wiki/Shrimp"][COLOR=black][FONT=Times New Roman][SIZE=3]shrimp[/SIZE][/FONT][/COLOR][/URL][SIZE=3][FONT=Times New Roman] which live inside the Venus' Flower Basket. However, a conclusive decision has not been reached; it may be that the light capabilities are simply a coincidental trait from a purely structural element.[/FONT][/SIZE][/COLOR][/LEFT]
[CENTER][COLOR=black][FONT=Arial][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/SPICULES.gif[/IMG][/FONT][/COLOR]

[COLOR=black][FONT=Arial][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/Spiculesff.gif[/IMG][/FONT][/COLOR][/CENTER]

Invertebrate protozoa (Movements)

[COLOR=white].........................................................................[/COLOR]
[youtube]QGAm6hMysTA[/youtube]

[B][B]Germ layers[/B]

[/B][COLOR=black]A [B]germ layer[/B] is a group of [/COLOR][URL="http://www.cssforum.com.pk/wiki/Cell_(biology)"][COLOR=black]cells[/COLOR][/URL][COLOR=black], formed during animal [/COLOR][URL="http://www.cssforum.com.pk/wiki/Embryogenesis"][COLOR=black]embryogenesis[/COLOR][/URL][COLOR=black]. Germ layers are particularly pronounced in the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Vertebrate"][COLOR=black]vertebrates[/COLOR][/URL][COLOR=black]; however, all [/COLOR][URL="http://www.cssforum.com.pk/wiki/Animal"][COLOR=black]animals[/COLOR][/URL][COLOR=black] more complex than [/COLOR][URL="http://www.cssforum.com.pk/wiki/Sea_sponge"][COLOR=black]sponges[/COLOR][/URL][COLOR=black] ([/COLOR][URL="http://www.cssforum.com.pk/wiki/Eumetazoa"][COLOR=black]eumetazoans[/COLOR][/URL][COLOR=black] and [/COLOR][URL="http://species.wikimedia.org/wiki/agnotozoa"][COLOR=black]agnotozoans[/COLOR][/URL][COLOR=black]) produce two or three [B]primary tissue layers[/B] (sometimes called primary germ layers). Animals with [/COLOR][URL="http://www.cssforum.com.pk/wiki/Symmetry_(biology)/lRadial_symmetry"][COLOR=black]radial symmetry[/COLOR][/URL][COLOR=black], like [/COLOR][URL="http://www.cssforum.com.pk/wiki/Cnidaria"][COLOR=black]cnidarians[/COLOR][/URL][COLOR=black], produce two germ layers (the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Ectoderm"][COLOR=black]ectoderm[/COLOR][/URL][COLOR=black] and [/COLOR][URL="http://www.cssforum.com.pk/wiki/Endoderm"][COLOR=black]endoderm[/COLOR][/URL][COLOR=black]) making them [/COLOR][URL="http://www.cssforum.com.pk/wiki/Diploblastic"][COLOR=black]diploblastic[/COLOR][/URL][COLOR=black]. Animals with [/COLOR][URL="http://www.cssforum.com.pk/wiki/Symmetry_(biology)/lBilateral_symmetry"][COLOR=black]bilateral symmetry[/COLOR][/URL][COLOR=black] produce a third layer between these two layers (appropriately called the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Mesoderm"][COLOR=black]mesoderm[/COLOR][/URL][COLOR=black]) making them [/COLOR][URL="http://www.cssforum.com.pk/wiki/Triploblastic"][COLOR=black]triploblastic[/COLOR][/URL][COLOR=black]. Germ layers eventually give rise to all of an animal’s [/COLOR][URL="http://www.cssforum.com.pk/wiki/Biological_tissue"][COLOR=black]tissues[/COLOR][/URL][COLOR=black] and [/COLOR][URL="http://www.cssforum.com.pk/wiki/Organ_(anatomy)"][COLOR=black]organs[/COLOR][/URL][COLOR=black] through the process of [/COLOR][URL="http://www.cssforum.com.pk/wiki/Organogenesis"][COLOR=black]organogenesis[/COLOR][/URL][COLOR=black].[/COLOR]
[COLOR=black]Among [/COLOR][URL="http://www.cssforum.com.pk/wiki/Animal"][COLOR=black]animals[/COLOR][/URL][COLOR=black], [/COLOR][URL="http://www.cssforum.com.pk/wiki/Sea_sponge"][COLOR=black]sponges[/COLOR][/URL][COLOR=black] show the simplest organization, having a single germ layer. Although they have differentiated cells (e.g. [/COLOR][URL="http://www.cssforum.com.pk/wiki/Choanocyte"][COLOR=black]collar cells[/COLOR][/URL][COLOR=black]), they lack true tissue coordination. [/COLOR][URL="http://www.cssforum.com.pk/wiki/Diploblastic"][COLOR=black]Diploblastic[/COLOR][/URL][COLOR=black] animals, [/COLOR][URL="http://www.cssforum.com.pk/wiki/Cnidaria"][COLOR=black]Cnidaria[/COLOR][/URL][COLOR=black] and [/COLOR][URL="http://www.cssforum.com.pk/wiki/Ctenophores"][COLOR=black]ctenophores[/COLOR][/URL][COLOR=black], show an increase in complexity, having two germ layers, the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Endoderm"][COLOR=black]endoderm[/COLOR][/URL][COLOR=black] and [/COLOR][URL="http://www.cssforum.com.pk/wiki/Ectoderm"][COLOR=black]ectoderm[/COLOR][/URL][COLOR=black]. Diploblastic animals are organized into recognisable tissues. All higher animals (from flatworms to humans) are [/COLOR][URL="http://www.cssforum.com.pk/wiki/Triploblastic"][COLOR=black]triploblastic[/COLOR][/URL][COLOR=black], possessing a [/COLOR][URL="http://www.cssforum.com.pk/wiki/Mesoderm"][COLOR=black]mesoderm[/COLOR][/URL][COLOR=black] in additition to the germ layers found in Diploblasts. Triploblastic animals develop recognisable organs.[/COLOR]

[B][COLOR=black]Development[/COLOR][/B]
[URL="http://www.cssforum.com.pk/wiki/Fertilisation"][COLOR=black]Fertilization[/COLOR][/URL][COLOR=black] leads to the formation of a [/COLOR][URL="http://www.cssforum.com.pk/wiki/Zygote"][COLOR=black]zygote[/COLOR][/URL][COLOR=black]. During the next stage, [/COLOR][URL="http://www.cssforum.com.pk/wiki/Cleavage_(embryo)"][COLOR=black]cleavage[/COLOR][/URL][COLOR=black], [/COLOR][URL="http://www.cssforum.com.pk/wiki/Mitosis"][COLOR=black]mitotic[/COLOR][/URL][COLOR=black] cell divisions transform the zygote into a tiny ball of cells, a [/COLOR][URL="http://www.cssforum.com.pk/wiki/Blastula"][COLOR=black]blastula[/COLOR][/URL][COLOR=black]. This early embryonic form undergoes [/COLOR][URL="http://www.cssforum.com.pk/wiki/Gastrulation"][COLOR=black]gastrulation[/COLOR][/URL][COLOR=black], forming a [/COLOR][URL="http://www.cssforum.com.pk/wiki/Gastrula"][COLOR=black]gastrula[/COLOR][/URL][COLOR=black] with either two or three layers (the germ layers). In all [/COLOR][URL="http://www.cssforum.com.pk/wiki/Vertebrate"][COLOR=black]vertebrates[/COLOR][/URL][COLOR=black], these are the forerunners of all adult tissues and organs.[/COLOR]
[COLOR=black]The appearance of the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Archenteron"][COLOR=black]archenteron[/COLOR][/URL][COLOR=black] marks the onset of gastrulation.[/COLOR]
[COLOR=black]In humans, after about three days, the zygote forms a solid mass of cells by mitotic division, called a [/COLOR][URL="http://www.cssforum.com.pk/wiki/Morula"][COLOR=black]morula[/COLOR][/URL][COLOR=black]. This then changes to a [/COLOR][URL="http://www.cssforum.com.pk/wiki/Blastocyst"][COLOR=black]blastocyst[/COLOR][/URL][COLOR=black], consisting of an outer layer called a [/COLOR][URL="http://www.cssforum.com.pk/wiki/Trophoblast"][COLOR=black]trophoblast[/COLOR][/URL][COLOR=black], and an inner cell mass called the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Embryoblast"][COLOR=black]embryoblast[/COLOR][/URL][COLOR=black]. Filled with uterine fluid, the blastocyst breaks out of the zona pellucida and undergoes [/COLOR][URL="http://www.cssforum.com.pk/wiki/Implantation"][COLOR=black]implantation[/COLOR][/URL][COLOR=black]. The inner cell mass initially has two layers: the hypoblast and epiblast. At the end of the second week, a [/COLOR][URL="http://www.cssforum.com.pk/wiki/Primitive_streak"][COLOR=black]primitive streak[/COLOR][/URL][COLOR=black] appears. The epiblast in this region moves towards the primitive streak, dives down into it, and forms a new layer, called the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Endoderm"][COLOR=black]endoderm[/COLOR][/URL][COLOR=black], pushing the hypoblast out of the way (this goes on to form the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Amnion"][COLOR=black]amnion[/COLOR][/URL][COLOR=black].) The epiblast keeps moving and forms a second layer, the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Mesoderm"][COLOR=black]mesoderm[/COLOR][/URL][COLOR=black]. The top layer is now called the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Ectoderm"][COLOR=black]ectoderm[/COLOR][/URL][COLOR=black].[/COLOR]

[B][COLOR=black]Endoderm[/COLOR][/B]
[COLOR=black]The [B]endoderm[/B] is one of the germ layers formed during animal embryogenesis. Cells migrating inward along the archenteron form the inner layer of the gastrula, which develops into the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Endoderm"][COLOR=black]endoderm[/COLOR][/URL][COLOR=black].[/COLOR]
[COLOR=black]The endoderm consists at first of flattened cells, which subsequently become columnar. It forms the epithelial lining of the whole of the digestive tube excepting part of the mouth and pharynx and the terminal part of the rectum (which are lined by involutions of the ectoderm). It also forms the lining cells of all the glands which open into the digestive tube, including those of the liver and pancreas; the epithelium of the auditory tube and tympanic cavity; the trachea, bronchi, and air cells of the lungs; the urinary bladder and part of the urethra; and the follicle lining of the thyroid gland and thymus.[/COLOR]
[COLOR=black]The [/COLOR][URL="http://www.cssforum.com.pk/wiki/Endoderm"][COLOR=black]endoderm[/COLOR][/URL][COLOR=black] forms: the stomach, the colon, the liver, the pancreas, the urinary bladder, the lining of the urethra, the epithelial parts of trachea, the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Lungs"][COLOR=black]lungs[/COLOR][/URL][COLOR=black], the pharynx, the thyroid, the parathyroid, and the intestines.[/COLOR]

[B][COLOR=black]Mesoderm[/COLOR][/B]
[COLOR=black]The [B]mesoderm[/B] germ layer forms in the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Embryo"][COLOR=black]embryos[/COLOR][/URL][COLOR=black] of [/COLOR][URL="http://www.cssforum.com.pk/wiki/Triploblastic"][COLOR=black]triploblastic[/COLOR][/URL][URL="http://www.cssforum.com.pk/wiki/Animal"][COLOR=black]animals[/COLOR][/URL][COLOR=black]. During [/COLOR][URL="http://www.cssforum.com.pk/wiki/Gastrulation"][COLOR=black]gastrulation[/COLOR][/URL][COLOR=black], some of the cells migrating inward contribute to the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Mesoderm"][COLOR=black]mesoderm[/COLOR][/URL][COLOR=black], an additional layer between the endoderm and the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Ectoderm"][COLOR=black]ectoderm[/COLOR][/URL][COLOR=black].[/COLOR]
[COLOR=black]This key innovation evolved hundreds of millions of years ago and led to the evolution of nearly all large, complex animals. The formation of a mesoderm led to the development of a [/COLOR][URL="http://www.cssforum.com.pk/wiki/Body_cavity"][COLOR=black]coelom[/COLOR][/URL][COLOR=black]. Organs formed inside a coelom can freely move, grow, and develop independently of the body wall while fluid cushions and protects them from shocks.[/COLOR]
[COLOR=black]The [/COLOR][URL="http://www.cssforum.com.pk/wiki/Mesoderm"][COLOR=black]mesoderm[/COLOR][/URL][COLOR=black] forms: skeletal muscle, the skeleton, the dermis of skin, connective tissue, the urogenital system, the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Heart"][COLOR=black]heart[/COLOR][/URL][COLOR=black], blood ([/COLOR][URL="http://www.cssforum.com.pk/wiki/Lymph"][COLOR=black]lymph[/COLOR][/URL][COLOR=black] cells), and the spleen.[/COLOR]

[B][COLOR=black]Ectoderm[/COLOR][/B]
[COLOR=black]The [B]ectoderm[/B] is the start of a tissue that covers the body surfaces. It emerges first and forms from the outermost of the germ layers.[/COLOR]
[COLOR=black]The [/COLOR][URL="http://www.cssforum.com.pk/wiki/Ectoderm"][COLOR=black]ectoderm[/COLOR][/URL][COLOR=black] forms: the central nervous system, the lens of the eye, cranial and sensory, the ganglia and nerves, pigment cells, head connective tissues, the epidermis, hair, and mammary glands[/COLOR]

[SIZE=4][COLOR=black][B]Neural crest[/B]
[/COLOR][/SIZE][COLOR=black]Because of its great importance, the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Neural_crest"][COLOR=black]neural crest[/COLOR][/URL][COLOR=black] is sometimes considered a fourth germ layer. It is, however, derived from the ectoderm.[/COLOR]

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/Cell_differentiation.gif[/IMG][/CENTER]

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/I10-55-gastrulation.jpg[/IMG][/CENTER]

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/germ-layers.jpg[/IMG][/CENTER]

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/Gastrulation.gif[/IMG][/CENTER]

[LEFT][B]Embryonic Membranes[/B][/LEFT]

The embryos of reptiles, birds, and mammals produce 4 extraembryonic membranes, the
amnion
yolk sac
chorion, and
allantois
In birds and most reptiles, the embryo with its extraembryonic membranes develops within a shelled egg.
The [B]amnion[/B] protects the embryo in a sac filled with [B]amniotic fluid[/B].
The [B]yolk sac[/B] contains yolk — the sole source of food until hatching. Yolk is a mixture of proteins and [URL="http://www.cssforum.com.pk/../C/Cholesterol.html/llipoprotein"][U][COLOR=#0000ff]lipoproteins[/COLOR][/U][/URL].
The [B]chorion[/B] lines the inner surface of the shell (which is permeable to gases) and participates in the exchange of O2 and CO2 between the embryo and the outside air.
The [B]allantois[/B] stores metabolic wastes (chiefly [URL="http://www.cssforum.com.pk/../U/UreaCycle.html/lUricAcid"][U][COLOR=#0000ff]uric acid[/COLOR][/U][/URL]) of the embryo and, as it grows larger, also participates in gas exchange.
With these four membranes, the developing embryo is able to carry on essential metabolism while sealed within the egg. Surrounded by amniotic fluid, the embryo is kept as moist as a fish embryo in a pond.
Although (most) mammals do not make a shelled egg, they do also enclose their embryo in an amnion. For this reason, the reptiles, birds, and mammals are collectively referred to as the [URL="http://www.cssforum.com.pk/../V/Vertebrates.html/lAmniota"][B][COLOR=#0000ff]amniota[/COLOR][/B][/URL].
Mammals fall into three groups that differ in the way they use the amniotic egg.

[B][LEFT]Monotremes[/LEFT]
[/B]
[LEFT]These primitive mammals produce a shelled egg like their reptilian ancestors. Only four species exist today: three species of spiny anteater (echidna) and the duckbill platypus[/LEFT]

[B][LEFT]Marsupial[/LEFT]
[/B]
[LEFT]Marsupials do not produce a shelled egg. The egg, which is poorly supplied with yolk, is retained for a time within the reproductive tract of the mother. The embryo penetrates the wall of the [B]uterus[/B]. The yolk sac provides a rudimentary connection to the mother's blood supply from which it receives food, oxygen, and other essentials. However, this interface between the tissues of the uterus and the extraembryonic membranes never becomes elaborately developed, and the young are born in a very immature state. [/LEFT]

[B][LEFT]Placental mammals[/LEFT]
[/B][LEFT]
In placental mammals, the extraembryonic membranes form a [B]placenta[/B] and [B]umbilical cord[/B], which connect the embryo to the mother's uterus in a more elaborate and efficient way. The blood supply of the developing fetus is continuous with that of the placenta. The placenta extracts food and oxygen from the uterus. Carbon dioxide and other wastes (e.g., urea) are transferred to the mother for disposal by her excretory organs.
Humans are placental mammals.
[/LEFT]

[CENTER][/CENTER]

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/I10-82-membranes.jpg[/IMG][/CENTER]

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/amnion.jpg[/IMG][/CENTER]

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/AmnioticEgg.gif[/IMG][/CENTER]

[CENTER][SIZE=3]EGG TYPES[/SIZE][/CENTER]
The Zygote
The zygote is [I]totipotent[/I] - it has the potential to develop into any other cell
Zygotes from different species differ in their yolk content:
[B]- [I]oligolecithal[/I] eggs - little yolk[/B]
[B]- [I]mesolecithal[/I] eggs - moderate amounts of yolk[/B]
[B]- [I]macrolecithal[/I] eggs - large amounts of yolk[/B]
[B]The distribution of yolk also differs:[/B]
[B]- oligolecithal eggs tend to be [I]isolecithal[/I] - yolk is distributed throughout the egg[/B]
[B]- meso- and macrolecithal eggs tend to be [I]telolecithal[/I] - yolk is segregated toward the [I]vegetal pole[/I], away from the [I]animal[/I] pole.[/B]

[B][CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/6JBM0504.gif[/IMG][/CENTER]
[/B]

[B][CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/6JBM0508.gif[/IMG][/CENTER]
[/B]

[B][CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/Image99.jpg[/IMG][/CENTER]
[/B]

[B]Cleavage[/B]

[B]Early cell division occurs without cell growth, and is termed cleavage[/B]
[B]The presence of yolk slows cleavage in proportion to its concentration[/B]
[B]- in [I]holoblastic cleavage[/I] cell divisions are complete[/B]
[B]- in [I]meroblastic cleavage[/I], the yolk is not completely divided[/B]
[B]Cleavage results in the [I]blastula[/I] - a mass of undifferentiated cells[/B]
[B]- cells have a high nucleus:cytoplasm ratio[/B]
[B]- cells are undifferentiated[/B]
[B]- the blastula contains a central cavity or [I]blastocoel[/I] [/B]

[B]Gastrulation[/B]
[B][I]Gastrulation [/I]is the transformation of the blastula into a [I]gastrula, [/I]a structure with three [I]germ layers[/I] and a [I]gastrocoel[/I][/B]
[B]Gastrulation begins at the [I]blastopore[/I] - a spot where proliferating cells fold into the blastocoel[/B]
[B]The gastrula has several important characters[/B]
[B]the three main body axes are defined [/B]
[B]cells acquire developmental fates[/B]
[B]- the [I]ectoderm[/I] will form the epidermis, nervous system, and sense organs[/B]
[B]- the [I]endoderm[/I] will form the gut lining and derivatives[/B]
[B]- the [I]mesoderm[/I] will form everything else[/B]

[B]Neurulation [/B]
[B][I]Neurulation[/I] is the initial formation of the nervous system[/B]
[B]- growth, cell differentiation and organogenesis begin[/B]
[B][I]Chordamesoderm[/I] cells aggregate to form the notochord[/B]
[B]The chordamesoderm [I]induces[/I] the dorsal ectoderm to form the neural tube[/B]
[B]- [I]induction [/I]involves turning on or off of specific genetic pathways in one type of cell following contact by another type of cell[/B]
[B]Mesoderm flanking the notochord becomes segmented into laterally paired blocks or [I]somites[/I][/B]
[B]different regions of the somites and lateral mesoderm have different developmental fates [/B]
[B][I]Pharyngeal pouches[/I] (6-9) develop by evaginations of the pharyngeal endoderm, which meet indentations of the ectoderm[/B]
[B]- they give rise to several important structures:[/B]
[B](e.g., the eardrum, jaws, glands)[/B]
[B][I]Placodes[/I] are ectodermal thickenings in the head[/B]
[B]- they contribute to the sense organs, and to the wandering cells[/B]
[B][I]Mesenchyme[/I] is the embryonic connective tissue [/B]
[B][I]- Wandering cells[/I] are mesenchyme cells that migrate through the embryo and form specific structures[/B]
[B][I]- Neural crest cells[/I] are wandering cells derived from ectoderm dorsal to the neural tube.[/B]
[B]- unique to vertebrates[/B]

[B]Organogenesis[/B]
[B][I]Organogenesis[/I] involves continued specialization of cells to form tissues[/B]
[B]- ectoderm and endoderm form predominantly [I]epithelium[/I] - sheets with tight intercellular junctions, flanking open space[/B]
[B]- mesoderm forms the matrix of the organs, including a variety of tissues [/B]
[B]Tissues combine to form organs[/B]
[B]Organs unite into organ systems[/B]

[CENTER][FONT=Times New Roman][B]Differences between the hearts: Vertebrates[/B][/FONT][/CENTER]

[FONT=Times New Roman]

[FONT=Times New Roman][SIZE=3]The fish heart (figure 1a) is much different than the amphibian/reptile/bird/mammal heart (figures 1b and c). Hearts are very complex--they're not just a bunch of random arteries and veins connecting tissue. Fish hearts simply draw in deoxygenated blood in a single atrium, and pump it out through a ventricle. This system is termed "single circulation", as blood enters the heart, gets pumped through the gills and out to the body, Blood pressure is low for oxygenated blood leaving the gills.

3 and 4 chambered hearts have a pulmonary circuit (pathways taking blood from heart to lung and back to heart) that is very complex and must be set up such that blood can travel from the heart to become oxygenated in the lungs and then be properly pumped back the heart and out to the body. The 3 (and 4) chambered heart has "double circulation" (figure 1b and c) and is quite different from "single circulation" (figure 1a) of fishes.

"Double circulation" has an interior circuit within the heart--blood enters the heart, leaves the heart and gets oxygenated, enters the heart again, and then gets pumped out to the body. Because "Double circulation" allows oxygenated blood to be pumped back into the heart before going out to the body, it pumps blood with much more pressure and much more vigorously than "single circulation". [/SIZE][/FONT]

[FONT=Times New Roman][SIZE=3]Though the 4 chambered heart has 2 atrium-ventricle pairs, both pairs do not do the same thing. There are 4 steps involved with blood entering the heart: 1) oxygen poor blood enters the first atrium. 2) oxygen poor blood is fed to the first ventricle, which pumps it out to the pulmonary circuit (lungs) where it is enriched in oxygen. 3) Oxygen rich blood just leaving the lungs is pumped back into the second atria. 4) Oxygen rich blood is then fed to the second ventricle, which pumps the oxygen rich blood out of the heart and back into the body for usage.

The 4 chambered heart differs from the 3 chambered heart in that it keeps oxygenated blood completely separate from de-oxygnated blood, because there is one ventricle for deoxgynated blood and one for oxygenated blood. In the 3 chambered heart, a single ventricle pumps both out of the heart, and there is some mixing between fresh and old blood. The 2 ventricle-4 chamber heart prevents mixing allows the blood leaving the heart to have far more oxygen than it would otherwise. This is good for enhancing the more fast paced lifestyle that birds and mammals tend to have, giving an advantage to having a 4 chambered heart.[/SIZE][/FONT]

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/hearts.jpg[/IMG][/CENTER]

[/FONT]

[CENTER][B]Hepatic portal system[/B][/CENTER]

[COLOR=black]In [/COLOR][URL="http://www.cssforum.com.pk/wiki/Human_anatomy"][COLOR=black]human anatomy[/COLOR][/URL][COLOR=black], the [B]hepatic portal system[/B] is the system of [/COLOR][URL="http://www.cssforum.com.pk/wiki/Vein"][COLOR=black]veins[/COLOR][/URL][COLOR=black] comprised of the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Hepatic_portal_vein"][COLOR=black]hepatic portal vein[/COLOR][/URL][COLOR=black] and its tributaries. It is also called the [B]portal venous system[/B], although it is not the only example of a [/COLOR][URL="http://www.cssforum.com.pk/wiki/Portal_venous_system"][COLOR=black]portal venous system[/COLOR][/URL][COLOR=black], and [B]splanchnic veins[/B], which is [I]not[/I] [/COLOR][URL="http://www.cssforum.com.pk/wiki/Synonymous"][COLOR=black]synonymous[/COLOR][/URL][COLOR=black] with [I]hepatic portal system[/I] and is imprecise (as it means [/COLOR][URL="http://www.cssforum.com.pk/wiki/Viscera"][I][COLOR=black]visceral[/COLOR][/I][/URL][COLOR=black][I] veins[/I] and not necessarily the [I]veins of the [/I][/COLOR][URL="http://www.cssforum.com.pk/wiki/Abdominal"][I][COLOR=black]abdominal[/COLOR][/I][/URL][COLOR=black][I] viscera[/I]).[/COLOR]

[SIZE=5][B][SIZE=4]Function[/SIZE][/B]

[/SIZE][COLOR=black]The portal venous system is responsible for directing blood from parts of the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Gastrointestinal_tract"][COLOR=black]gastrointestinal tract[/COLOR][/URL][COLOR=black] to the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Liver"][COLOR=black]liver[/COLOR][/URL][COLOR=black]. Substances absorbed in the small intestine travel first to the liver for processing before continuing to the heart. Not all of the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Gastrointestinal_tract"][COLOR=black]gastrointestinal tract[/COLOR][/URL][COLOR=black] is part of this system. The system extends from about the lower portion of the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Esophagus"][COLOR=black]esophagus[/COLOR][/URL][COLOR=black] to the upper part of the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Anal_canal"][COLOR=black]anal canal[/COLOR][/URL][COLOR=black]. It also includes venous drainage from the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Spleen"][COLOR=black]spleen[/COLOR][/URL][COLOR=black] and [/COLOR][URL="http://www.cssforum.com.pk/wiki/Pancreas"][COLOR=black]pancreas[/COLOR][/URL][COLOR=black].[/COLOR]
[COLOR=black]Many drugs that are absorbed through the [/COLOR][URL="http://www.cssforum.com.pk/wiki/GI_tract"][COLOR=black]GI tract[/COLOR][/URL][COLOR=black] are substantially metabolized by the liver before reaching general circulation. This is known as the [/COLOR][URL="http://www.cssforum.com.pk/wiki/First_pass_effect"][COLOR=black]first pass effect[/COLOR][/URL][COLOR=black]. As a consequence, certain drugs can only be taken via certain routes. For example, [/COLOR][URL="http://www.cssforum.com.pk/wiki/Nitroglycerin"][COLOR=black]nitroglycerin[/COLOR][/URL][COLOR=black] cannot be swallowed because the liver would inactivate the medication, but it can be taken [/COLOR][URL="http://www.cssforum.com.pk/wiki/Sublingual"][COLOR=black]under the tongue[/COLOR][/URL][COLOR=black] or transdermal (through the skin) and thus is absorbed in a way that bypasses the portal venous system.[/COLOR]
[COLOR=black]Blood flow to the liver is unique in that it receives both oxygenated and deoxygenated blood. As a result, the partial pressure of oxygen (pO2) and perfusion pressure of portal blood are lower than in other organs of the body. Blood passes from branches of the portal vein through cavities between "plates" of [/COLOR][URL="http://www.cssforum.com.pk/wiki/Hepatocytes"][COLOR=black]hepatocytes[/COLOR][/URL][COLOR=black] called [/COLOR][URL="http://www.cssforum.com.pk/wiki/Liver_sinusoid"][COLOR=black]sinusoids[/COLOR][/URL][COLOR=black]. Blood also flows from branches of the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Hepatic_artery"][COLOR=black]hepatic artery[/COLOR][/URL][COLOR=black] and mixes in the sinusoids to supply the hepatocytes with oxygen. This mixture [/COLOR][URL="http://www.cssforum.com.pk/wiki/Percolation"][COLOR=black]percolates[/COLOR][/URL][COLOR=black] through the sinusoids and collects in a central vein which drains into the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Hepatic_vein"][COLOR=black]hepatic vein[/COLOR][/URL][COLOR=black]. The hepatic vein subsequently drains into the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Inferior_vena_cava"][COLOR=black]inferior vena cava[/COLOR][/URL][COLOR=black].[/COLOR]
[COLOR=black]Large veins that are considered part of the [I]portal venous system[/I] are the:[/COLOR]
[URL="http://www.cssforum.com.pk/wiki/Hepatic_portal_vein"][COLOR=black]Hepatic portal vein[/COLOR][/URL]
[URL="http://www.cssforum.com.pk/wiki/Splenic_vein"][COLOR=black]Splenic vein[/COLOR][/URL]
[COLOR=black]Roughly, the portal venous system corresponds to areas supplied by the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Celiac_trunk"][COLOR=black]celiac trunk[/COLOR][/URL][COLOR=black], the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Superior_mesenteric_artery"][COLOR=black]superior mesenteric artery[/COLOR][/URL][COLOR=black], and the [/COLOR][URL="http://www.cssforum.com.pk/wiki/Inferior_mesenteric_artery"][COLOR=black]inferior mesenteric artery[/COLOR][/URL][COLOR=black].[/COLOR]

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/hepatic.gif[/IMG][/CENTER]

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/hepatic20portal20system.jpg[/IMG][/CENTER]

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/portsys.gif[/IMG][/CENTER]

The hepatic portal system begins in the capillaries of the digestive organs and ends in the portal vein. Consequently, portal blood contains substances absorbed by the stomach and intestines. Portal blood is passed through the hepatic lobules where nutrients and toxins are absorbed, excreted or converted.
Restriction of outflow through the hepatic portal system can lead to portal hypertension. Portal hypertension is most often associated with cirrhosis. Patients usually present with splenomegaly, ascites, GI bleeding and/or portal systemic encephalopathy.
The consequences of portal hypertension are due to portal systemic anastomosis formed by the body as an attempt to bypass the obstructed liver circulation. These collateral vessels form along the falciform ligament, diaphragm, spleen, stomach and peritoneum. The collaterals find their way to the renal vein where blood drained from the digestive organs is let into the systemic circulation.

[CENTER][B]Blood[/B][/CENTER]

[B][I][SIZE=6][COLOR=#808080][SIZE=6][COLOR=#808080][CENTER]Blood Components[/CENTER]
[/COLOR][/SIZE][/COLOR][/SIZE][/I][/B][SIZE=6][COLOR=#808080][SIZE=6][COLOR=#808080]
[/COLOR][/SIZE][/COLOR][/SIZE][SIZE=6][COLOR=#808080][SIZE=6][COLOR=#808080]
[/COLOR][/SIZE][/COLOR][/SIZE][FONT=Times New Roman][SIZE=1][FONT=Times New Roman][SIZE=1]
[/SIZE][/FONT][/SIZE][/FONT][SIZE=3]Normally, 7-8% of human body weight is from blood. In adults, this amounts to 4-5 quarts of blood. This essential fluid carries out the critical functions of transporting oxygen and nutrients to our cells and getting rid of carbon dioxide, ammonia, and other waste products. In addition, it plays a vital role in our immune system and in maintaining a relatively constant body temperature. Blood is a highly specialized tissue composed of many different kinds of components. Four of the most important ones are red cells, white cells, platelets, and plasma. All humans produce these blood components--there are no populational or regional differences.[/SIZE]

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/19432.jpg[/IMG][/CENTER]

[B][SIZE=5][COLOR=#808080][SIZE=5][COLOR=#808080][CENTER]Red Cells[/CENTER]
[/COLOR][/SIZE][/COLOR][/SIZE][/B][SIZE=5][COLOR=#808080][SIZE=5][COLOR=#808080]
[/COLOR][/SIZE][/COLOR][/SIZE][SIZE=5][COLOR=#808080][SIZE=5][COLOR=#808080]
[/COLOR][/SIZE][/COLOR][/SIZE]Red cells, or [B]erythrocytes[/B]
, are relatively large microscopic cells without nuclei. In this latter trait, they are similar to the primitive [URL="http://www.cssforum.com.pk/glossary.htm/lprokaryotic"][U][COLOR=#0000ff]prokaryotic cells[/COLOR][/U][/URL] of bacteria. Red cells normally make up 40-50% of the total blood volume. They transport oxygen from the lungs to all of the living tissues of the body and carry away carbon dioxide. The red cells are produced continuously in our bone marrow from [URL="http://www.cssforum.com.pk/glossary.htm/lstem_cells"][U][COLOR=#0000ff]stem cells[/COLOR][/U][/URL] at a rate of about 2-3 million cells per second. [B]Hemoglobin[/B]
is the gas transporting [URL="http://www.cssforum.com.pk/glossary.htm/lproteins"][U][COLOR=#0000ff]protein[/COLOR][/U][/URL] molecule that makes up 95% of a red cell. Each red cell has about 270,000,000 iron-rich hemoglobin molecules. People who are anemic generally have a deficiency in red cells. The red color of blood is primarily due to oxygenated red cells. Human fetal hemoglobin molecules differ from those produced by adults in the number of amino acid chains. Fetal hemoglobin has three chains, while adults produce only two. As a consequence, fetal hemoglobin molecules attract and transport relatively more oxygen to the cells of the body.

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/RBC-Production-Cycle.gif[/IMG][/CENTER]

[B][SIZE=5][COLOR=#808080][SIZE=5][COLOR=#808080][CENTER]White Cells[/CENTER]
[/COLOR][/SIZE][/COLOR][/SIZE][/B][SIZE=5][COLOR=#808080][SIZE=5][COLOR=#808080]
[/COLOR][/SIZE][/COLOR][/SIZE][SIZE=5][COLOR=#808080][SIZE=5][COLOR=#808080]
[/COLOR][/SIZE][/COLOR][/SIZE]White cells, or [B]leukocytes[/B]
, exist in variable numbers and types but make up a very small part of blood's volume--normally only about 1% in healthy people. Leukocytes are not limited to blood. They occur elsewhere in the body as well, most notably in the spleen, liver, and lymph glands. Most are produced in our bone marrow from the same kind of stem cells that produce red blood cells. Others are produced in the thymus gland, which is at the base of the neck. Some white cells (called lymphocytes
) are the first responders for our immune system. They seek out, identify, and bind to alien protein on [URL="http://www.cssforum.com.pk/glossary.htm/lbacteria"][U][COLOR=#0000ff]bacteria[/COLOR][/U][/URL], [URL="http://www.cssforum.com.pk/glossary.htm/lvirus"][U][COLOR=#0000ff]viruses[/COLOR][/U][/URL], and [URL="http://www.cssforum.com.pk/glossary.htm/lfungi"][U][COLOR=#0000ff]fungi[/COLOR][/U][/URL] so that they can be removed. Other white cells (called granulocytes
and macrophages
) then arrive to surround and destroy the alien cells. They also have the function of getting rid of dead or dying blood cells as well as foreign matter such as dust and asbestos. Red cells remain viable for only about 4 months before they are removed from the blood and their components recycled in the spleen. Individual white cells usually only last 18-36 hours before they also are removed, though some types live as much as a year. The description of white cells presented here is a simplification. There are actually many specialized sub-types of them that participate in different ways in our immune responses.

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/untitled.jpg[/IMG][/CENTER]

[B][SIZE=5][COLOR=#808080][SIZE=5][COLOR=#808080][CENTER]Platelets[/CENTER]
[/COLOR][/SIZE][/COLOR][/SIZE][/B][SIZE=5][COLOR=#808080][SIZE=5][COLOR=#808080]
[/COLOR][/SIZE][/COLOR][/SIZE][SIZE=5][COLOR=#808080][SIZE=5][COLOR=#808080]
[/COLOR][/SIZE][/COLOR][/SIZE]Platelets
, or [B]thrombocytes[/B]
, are cell fragments without nuclei that work with blood clotting chemicals at the site of wounds. They do this by adhering to the walls of blood vessels, thereby plugging the rupture in the [URL="http://www.cssforum.com.pk/glossary.htm/lvascular"][U][COLOR=#0000ff]vascular[/COLOR][/U][/URL] wall. They also can release coagulating chemicals which cause clots to form in the blood that can plug up narrowed blood vessels. There are more than a dozen types of blood clotting factors and platelets that need to interact in the blood clotting process. Recent research has shown that platelets help fight infections by releasing proteins that kill invading bacteria and some other microorganisms. In addition, platelets stimulate the immune system. Individual platelets are about 1/3 the size of red cells. They have a lifespan of 9-10 days. Like the red and white blood cells, platelets are produced in bone marrow from stem cells.

[CENTER][IMG]http://i723.photobucket.com/albums/ww237/alphamalik/cell_platelets_web.jpg[/IMG][/CENTER]

[B][SIZE=5][COLOR=#808080][SIZE=5][COLOR=#808080][CENTER]Plasma[/CENTER]
[/COLOR][/SIZE][/COLOR][/SIZE][/B][SIZE=5][COLOR=#808080][SIZE=5][COLOR=#808080]
[/COLOR][/SIZE][/COLOR][/SIZE][SIZE=5][COLOR=#808080][SIZE=5][COLOR=#808080]
[/COLOR][/SIZE][/COLOR][/SIZE]Plasma
is the relatively clear liquid water (92+%), sugar, fat, protein and salt solution which carries the red cells, white cells, platelets, and some other chemicals. Normally, 55% of our blood's volume is made up of plasma. About 95% of it consists of water. As the heart pumps blood to cells throughout the body, plasma brings nourishment to them and removes the waste products of [URL="http://www.cssforum.com.pk/glossary.htm/lmetabolism"][U][COLOR=#0000ff]metabolism[/COLOR][/U][/URL]. Plasma also contains blood clotting factors, sugars, [URL="http://www.cssforum.com.pk/glossary.htm/llipid"][U][COLOR=#0000ff]lipids[/COLOR][/U][/URL], vitamins, minerals, [URL="http://www.cssforum.com.pk/glossary.htm/lhormones"][U][COLOR=#0000ff]hormones[/COLOR][/U][/URL], [URL="http://www.cssforum.com.pk/glossary.htm/lenzyme"][U][COLOR=#0000ff]enzymes[/COLOR][/U][/URL], [URL="http://www.cssforum.com.pk/glossary.htm/lantibodies"][U][COLOR=#0000ff]antibodies[/COLOR][/U][/URL], and other [URL="http://www.cssforum.com.pk/glossary.htm/lproteins"][U][COLOR=#0000ff]proteins[/COLOR][/U][/URL]. It is likely that plasma contains some of every protein produced by the body--approximately 500 have been identified in human plasma so far.