Book - Stoehr's Histology 1-1 - Revision history

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2015-11-09T11:03:26Z

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	Fig. 2. Fibrils in a ~~Nkrve~~ Cell.		Fig. 2. Fibrils in a Nerve Cell.


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	Fig. 4.~~Vacl-oi.~~ in Young Fat cells.		Fig. 4.Vacuole in Young Fat cells.


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	3. Vacuoles. Well defined, round spaces,		3. Vacuoles. Well defined, round spaces, apparently empty, may occur in the protoplasm due to the formation of droplets of fat or of watery fluids. They vary greatly in size, and one or several of these vacuoles may be found in a single cell.
	apparently empty, may occur in the protoplasm
	due to the formation of droplets of fat or of watery
	fluids. They vary greatly in size, and one or several of these vacuoles may be found in a single cell.

	4. Canals, of two sorts* (a) Secreton^ canals,		4. Canals, of two sorts* (a) Secreton^ canals, which occur in protoplasm of gland cells and empty into the gland cavity or lumen; (i) fine tubes which communicate with lymphatic spaces outside of the cell* They are found in all cells of higher physiological importance, but are lacking in most of the supporting tissues and in stratified epithehum. They presumably share in nourishing tlie cell and have been called the ** trophospongium," This name, implying a network, is due to the opinion, not established however, that the Uttle canals are occupied by cell processes extending into the protoplasm from adjoining '^capsule cells." Other investigators consider that the trophospongium canals are wholly within the cell and constitute a form of vacuole.
	which occur in protoplasm of gland cells and
	empty into the gland cavity or lumen; (i) fine
	tubes which communicate with lymphatic spaces
	outside of the cell* They are found in all cells of
	higher physiological importance, but are lacking
	in most of the supporting tissues and in stratified
	epithehum. They presumably share in nourishing tlie cell and have been called the ** trophospongium," This name, implying a network,
	is due to the opinion, not established however,
	that the Uttle canals are occupied by cell processes extending into the protoplasm from adjoining '^capsule cells." Other investigators consider
	that the trophospongium canals are wholly within
	the cell and constitute a form of vacuole.

	5. Closed networks, which do not open at		5. Closed networks, which do not open at the periphery of the cell. This ** reticular apparatus'* has been found in nen-e, cartilage and
	the peripher}* of the cell. This ** reticular apparatus'* has been found in nen-e, cartilage and
	many gland cells. Its significance is unknown,		many gland cells. Its significance is unknown,

	6. Inclusions. These are foreign bodies		6. Inclusions. These are foreign bodies which have been ingested by the cell and are found in the protoplasm. Inert crystalloid substances formed within the cell are also called inclusions. The name "paranucleus" has been applied to various structures, such as a dead cell ingested by a living one, a transformation of the centrosome, or a mass of secretion. Some of the paranuclei are still obscure.
	which have been ingested by the cell and are
	found in the protoplasm. Inert crystalloid substances formed within the cell are also called
	inclusions. The name "paranucleus" has been
	applied to various structures, such as a dead cell ^
	ingested by a living one, a transformation of the
	centrosome, or a mass of secretion. Some of the
	paranuclei are still obscure.

	===Nucleus===		===Nucleus===
	The nucleus (Latin, nuclms, 'the kernel of a nut"; Greek, ^i^jov, "a nut') is a well defined,		The nucleus (Latin, nuclms, 'the kernel of a nut"; Greek, ^i^jov, "a nut') is a well defined, refractive body of vesicular form situated within

	refractive body of vesicular form situated within
	membrane enclosing a mass of ground substance,		membrane enclosing a mass of ground substance,
	there is a fibrillar network associated with some deeply staining bodies. The ground substance and network are closely		there is a fibrillar network associated with some deeply staining bodies. The ground substance and network are closely
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	:''Online editor - "Cell wall" is a historic term for the cell membrane and the term is now used to describe non-membrane structures in outside plant cells and outside bacterial membranes.''		:''Online editor - "Cell wall" is a historic term for the cell membrane and the term is now used to describe non-membrane structures in outside plant cells and outside bacterial membranes.''

	A cell wall or cell membrane is an independent membranous layer covering a cell and being clearly distinct from the underlying protoplasm. It is not an essential constituent of a cell. Often it is lacking, and when present it is either a modification or a secretion of the peripheral protoplasm. If the membrane surrounds the cell on all sides it is called a pellicula;		A cell wall or cell membrane is an independent membranous layer covering a cell and being clearly distinct from the underlying protoplasm. It is not an essential constituent of a cell. Often it is lacking, and when present it is either a modification or a secretion of the peripheral protoplasm. If the membrane surrounds the cell on all sides it is called a pellicula; if it is on only one side, covering the free surface, it is a cuiicula. (The former term is seldom used.) Cells may unite with one another by protoplasmic processes of varying length and width, thus forming cellular networks; or they may completely fuse so that their nuclei appear irregularly distributed through a single mass of protoplasm. Such a formation is a syncytium [plasmodium]. This name is applied also to such structures as the striated muscle fiber, due not to the fusion of cells but to the multipUcation of nuclei in an undivided mass of protoplasm.
	if it is on only one side, covering the free surface, it is a cuiicula. (The former term is seldom used.) Cells may unite with one another by protoplasmic processes of varying length and width, thus forming cellular networks; or they may completely fuse so that their nuclei appear irregularly distributed through a single mass of protoplasm. Such a formation
	is a syncytium [plasmodium]. This name is applied also to such structures
	as the striated muscle fiber, due not to the fusion of cells but to the multipUcation of nuclei in an undivided mass of protoplasm.


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	and in giant cells.		and in giant cells.

	The size of cells ranges from that of the yolks of birds' eggs ~~â€”~~		The size of cells ranges from that of the yolks of birds' eggs - which are single cells at least shortly before being laid - down to microscopic structures four thousandths of a millimeter in diameter. The
	which are single cells at least shortly before being laid ~~â€”~~ down to microscopic structures four thousandths of a millimeter in diameter. The		thousandth of a millimeter is the unit employed in microscopic measurements. It is called a micron, and its symbol is the Greek letter /jl. The small cells referred to are therefore four microns, 4 /i, in diameter. \The
	thousandth of a millimeter is the unit employed in microscopic measurements. It is called a micron, and its symbol is the Greek letter /jl. The		size of any structure in a section of human tissue may be roughly estimated by comparing its dimensions with the diameter of a red blood corpuscle found in the same section. These red corpuscles are quite uniformly
	small cells referred to are therefore four microns, 4 /i, in diameter. \The
	size of any structure in a section of human tissue may be roughly estimated
	by comparing its dimensions with the diameter of a red blood corpuscle
	found in the same section. These red corpuscles are quite uniformly
	7.5 /i in diameter.;		7.5 /i in diameter.;

	==Vital Phenomena==		==Vital Phenomena==

	The vital properties of cells are more ~~fuUy~~ treated in text-books of physiology. They include the phenomena of irritability, metabolism, contractility, conductivity, and reproduction. Under irritability may be grouped the response of cells to stimuli of various sorts such as heat,		The vital properties of cells are more fully treated in text-books of physiology. They include the phenomena of irritability, metabolism, contractility, conductivity, and reproduction. Under irritability may be grouped the response of cells to stimuli of various sorts such as heat,
	light, electricity, chemical reagents, the nervous impulse, or mechanical		light, electricity, chemical reagents, the nervous impulse, or mechanical
	interference. Metabolism, in a wide sense, includes the ingestion and assimilation of food, the elaboration and secretion of desirable products,		interference. Metabolism, in a wide sense, includes the ingestion and assimilation of food, the elaboration and secretion of desirable products,
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	the equator of the spindle in such a way that their apices point toward the axis of the spindle and their free ends radiate from it in all directions, Fig. II. At either apex of the spindle is the centrosome surrounded by the centrosphere, the radiating fibrils of which are now called polar radiations. K the cell at this stage is viewed from one of its ends or poles, the chromosomes together constitute a single star and this mitotic figure is accordingly		the equator of the spindle in such a way that their apices point toward the axis of the spindle and their free ends radiate from it in all directions, Fig. II. At either apex of the spindle is the centrosome surrounded by the centrosphere, the radiating fibrils of which are now called polar radiations. K the cell at this stage is viewed from one of its ends or poles, the chromosomes together constitute a single star and this mitotic figure is accordingly called the monaster. Fig. 15 shows the monaster both in side and polar views.
	called the monaster. Fig. 15 shows the monaster both in side and polar views.

	In the prophase, before the chromosomes have formed, the convoluted		In the prophase, before the chromosomes have formed, the convoluted
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	Fig. 16. ~~Mitosks~~ in Human Cancer Cells. (From Wilson, after Galeotti.) a. Asymmetrical mitosis with unequal distribution of chromatin; bÂ» tripolar mitosis; c* quadripolar mitosis.		Fig. 16. Mitosis in Human Cancer Cells. (From Wilson, after Galeotti.) a. Asymmetrical mitosis with unequal distribution of chromatin; bÂ» tripolar mitosis; c* quadripolar mitosis.


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	Every specimen of human tissue exhibits some phase of cytomorphosis. In some sections a series of cells may be observed from those but slightly differentiated, to the dead in process of removal. Because of the similarity and possible identity of this normal, "physiological" regression, with that found in diseased tissues, such specimens should be studied with particular care.		Every specimen of human tissue exhibits some phase of cytomorphosis. In some sections a series of cells may be observed from those but slightly differentiated, to the dead in process of removal. Because of the similarity and possible identity of this normal, "physiological" regression, with that found in diseased tissues, such specimens should be studied with particular care.


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Mitosis

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Cytomorphosis

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	Fig. iS.~~â€”Nuclki~~ of Striated Muscle Fibers from		Fig. 18. Nuclei of Striated Muscle Fibers from Young Salamanders (Necturus). (Eycleshymer.)
	Young Salamanders (Necturus). (Eycleshymer.)

	A, From a 7 mm. embryo ; B, from one of 26 mm.; ch.,		A, From a 7 mm. embryo ; B, from one of 26 mm.; ch., chromatin knot ; g. s., ground substance ; I, linin fibril; n., nucleolus ; n. m., nuclear membrane.
	chromatin knot ; g. s., ground substance ; I, linin
	fibril; n., nucleolus ; n. m., nuclear membrane.


	In a few organs the cells perish, but no new ones form, so that the organ to		In a few organs the cells perish, but no new ones form, so that the organ to which they belong atrophies. Thus the mesonephros (Wolffian body) largely disappears during fetal life; the thymus becomes vestigial in the adult; and the ovary in later years loses its chief function through the degeneration of its cells.
	which they belong atrophies. Thus the mesonephros (Wolffian body)
	largely disappears during fetal life; the thymus becomes vestigial in the
	adult; and the ovary in later years loses its chief function through the
	degeneration of its cells.

	The optical effects of regression cannot at present be properly classified. In a characteristic form, known as "cloudy swelling," the cell enlarges, becoming pale and opaque. In another form the cjbII shrinks and
	~~stains deeply, becoming either irregularly granular or homogeneous and~~
	hyaline. The nucleus may disappear as if in solution (karyolysis, chromatolysis), or it may fragment and be scattered through the protoplasm (karyorhexis). If the process of degeneration is slow, the cell may divide by
	~~amitosis. It may be able to receive nutriment which it cannot assimilate,~~
	~~and thus its protoplasm may be infiltrated with fat and appear vacuolated.~~
	~~It may form abnormal intercellular substances, for example, amyloid, or~~
	~~the existing intercellular substances may become changed to mucoid~~
	~~masses or have lime salts deposited in them. In short, together with~~
	~~optical changes in the cell substance there is often an impairment or~~
	~~perversion of function.~~

	The ~~removal~~ of ~~dead cells is accomplished~~ in ~~several ways~~. ~~Those~~		The optical effects of regression cannot at present be properly classified. In a characteristic form, known as "cloudy swelling," the cell enlarges, becoming pale and opaque. In another form the cjbII shrinks and stains deeply, becoming either irregularly granular or homogeneous and hyaline. The nucleus may disappear as if in solution (karyolysis, chromatolysis), or it may fragment and be scattered through the protoplasm (karyorhexis). If the process of degeneration is slow, the cell may divide by amitosis. It may be able to receive nutriment which it cannot assimilate, and thus its protoplasm may be infiltrated with fat and appear vacuolated. It may form abnormal intercellular substances, for example, amyloid, or the existing intercellular substances may become changed to mucoid masses or have lime salts deposited in them. In short, together with optical changes in the cell substance there is often an impairment or perversion of function.
	~~near~~ the ~~external or internal surfaces~~ of the ~~body are usually shed or desquamated~~, and ~~such cells~~ may be ~~found in the saliva~~ and ~~urine~~. ~~Those~~
	~~which are within~~ the ~~body~~ may ~~be dissolved by chemical action~~ or ~~devoured~~
	~~by phagocytes~~.

	Every specimen of human tissue exhibits some phase of cytomorphosis.
	In some sections a series of cells may be observed from those but slightly		The removal of dead cells is accomplished in several ways. Those near the external or internal surfaces of the body are usually shed or desquamated, and such cells may be found in the saliva and urine. Those which are within the body may be dissolved by chemical action or devoured by phagocytes.
	differentiated, to the dead in process of removal. Because of the similarity
	and possible identity of this normal, "physiological" regression, with that
	found in diseased tissues, such specimens should be studied with particular		Every specimen of human tissue exhibits some phase of cytomorphosis. In some sections a series of cells may be observed from those but slightly differentiated, to the dead in process of removal. Because of the similarity and possible identity of this normal, "physiological" regression, with that found in diseased tissues, such specimens should be studied with particular care.
	care.

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=Amitosis

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	==Amitosis=		===Amitosis===

	Amitosis or direct cell division takes place without spindle formation		Amitosis or direct cell division takes place without spindle formation

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Amoeboid Motion

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	===Amoeboid Motion===		===Amoeboid Motion===

	The imicellular animal, Amoeba, exhibits a type of motility known		The imicellular animal, Amoeba, exhibits a type of motility known as amoeboid, which has been observed in many sorts of cells in the vertebrate body. In marked cases, as in certain white blood corpuscles
	as amoeboid, which has been observed in many sorts of cells in the vertebrate body. In marked cases, as		(the leucocytes), the cell protoplasm sends out fine or coarse processes which divide or fuse with one another, causing the cell to assume a
	in certain white blood corpuscles
	(the leucocytes), the cell protoplasm
	sends out fine or coarse processes
	which divide or fuse with one ~~an/^^ ^5L ^^ ^fe d i ^^JP other~~, causing the cell to assume a

	sÂ«', 5 6 8 10 Minuses. g^eat Variety of forms. The processes may be retracted, or they may		sÂ«', 5 6 8 10 Minuses. g^eat Variety of forms. The processes may be retracted, or they may

	Fig. 8. Leucocytes of a Frog. X 560. ~~, - - ,~~		Fig. 8. Leucocytes of a Frog. X 560.

	Changes in form obsen ed duriiiR ten minutes : bCCOme attached SOmCWhcrC and		Changes in form obsen ed duriiiR ten minutes : bCCOme attached SOmCWhcrC and
	o, at the beeinninj; of the observation; ~~J4, a j .1 â€¢ j ^ ^i_ n i_ j~~		o, at the beeinninj; of the observation;

	~~half minute later, etc. draw the rcmamdcr of the cell body after them, the result of which is~~
	~~locomotion or the so-called wandering of the cell. Such wandering cells~~
	play an important part in the economy of the animal body. Their processes can flow around granules or cells and thus enclose them in protoplasm. Some of these ingested bodies may be assimilated by the cell as
	~~a result of complex chemical and osmotic reactions. Cells which feed on~~
	~~foreign particles and can alter or digest them are known as phagocytes.~~
	~~Amoeboid movements take place very slowly. In preparations from warmblooded animals they may be accelerated by gently heating the object.~~

	~~Another form~~ of ~~motion~~, which~~, however, does not occur~~ in ~~living~~		half minute later, etc. draw the remaindrr of the cell body after them, the result of which is locomotion or the so-called wandering of the cell. Such wandering cells play an important part in the economy of the animal body. Their processes can flow around granules or cells and thus enclose them in protoplasm. Some of these ingested bodies may be assimilated by the cell as a result of complex chemical and osmotic reactions. Cells which feed on foreign particles and can alter or digest them are known as phagocytes. Amoeboid movements take place very slowly. In preparations from warmblooded animals they may be accelerated by gently heating the object.
	cells~~, consists~~ in ~~an oscillation~~ of ~~minute granules within~~ the cell. ~~This~~
	~~may be due to diffusion currents~~ or ~~to the Brownian phenomena~~. It
	may ~~often~~ be ~~seen in salivary corpuscles~~.

			Another form of motion, which, however, does not occur in living cells, consists in an oscillation of minute granules within the cell. This may be due to diffusion currents or to the Brownian phenomena. It may often be seen in salivary corpuscles.

	==Formation and Reproduction of Cells==		==Formation and Reproduction of Cells==

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Protoplasm

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	the nucleus is ordinarily called protoplasm.		the nucleus is ordinarily called protoplasm.

	[[File:Lewis1906 fig001.jpg\|~~400px~~]]		[[File:Lewis1906 fig001.jpg\|600px]]

	'''Fig. 1.''' Diagram of a Cell. Microsomes and filar mass only partly sketched.		'''Fig. 1.''' Diagram of a Cell. Microsomes and filar mass only partly sketched.
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	ingested by a living one, a transformation of the		ingested by a living one, a transformation of the
	centrosome, or a mass of secretion. Some of the		centrosome, or a mass of secretion. Some of the
	paranuclei are still obscure.		paranuclei are still obscure.

	===Nucleus===		===Nucleus===

Z8600021: /* The Cell */

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The Cell

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	the nucleus is ordinarily called protoplasm.		the nucleus is ordinarily called protoplasm.

			[[File:Lewis1906 fig001.jpg\|400px]]

			'''Fig. 1.''' Diagram of a Cell. Microsomes and filar mass only partly sketched.
	Fig. 1. Diagram of a Cell. Microsomes and filar mass only partly sketched.

	Protoplasm is a heterogeneous mixture of substances forming a soft, viscid mass of neutral reaction. In distilled water it swells but does not disappear. It consists of water, salts and organic substances, some in solution, and some in a colloidal state. The organic bodies are classed as proteids, glycogen or some allied carbohydrates, and lipoid (fat-like) bodies. Protoplasm may exist in a numberless variety of forms.		Protoplasm is a heterogeneous mixture of substances forming a soft, viscid mass of neutral reaction. In distilled water it swells but does not disappear. It consists of water, salts and organic substances, some in solution, and some in a colloidal state. The organic bodies are classed as proteids, glycogen or some allied carbohydrates, and lipoid (fat-like) bodies. Protoplasm may exist in a numberless variety of forms.
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	Pen-knife sharpened as keen as a razor, I cut a piece of it off and thereby left		Pen-knife sharpened as keen as a razor, I cut a piece of it off and thereby left
	the surface of it exceedingly smooth, then examining it very diligently with a		the surface of it exceedingly smooth, then examining it very diligently with a
	microscope, me thought I could perceive it to be a little porous. . . . These pores or cells were not very deep but consisted of a great many little Boxes In this way one of the briefest and most important of scientific terms was introduced.		microscope, me thought I could perceive it to be a little porous. . . . These pores or cells were not very deep but consisted of a great many little Boxes In this way one of the briefest and most important of scientific terms was introduced.

	==Form and Size of Cells==		==Form and Size of Cells==

Z8600021 at 00:39, 6 February 2015

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	A cell may be defined as a structural element of limited dimensions which under certain conditions can perform the functions of assimilation,		A cell may be defined as a structural element of limited dimensions which under certain conditions can perform the functions of assimilation,
	growth, and reproduction.^ Because of these possibilities a cell may be		growth, and reproduction. Because of these possibilities a cell may be considered an elementary organism. It is described as a mass of protoplasm containing a nucleus. A third element, the centrosome, is found
	considered an elementary organism. It is described as a mass of protoplasm containing a nucleus. A third element, the centrosome, is found
	in the cells of animals, but not in those of the higher plants. The centrosome becomes prominent when a cell is about to divide. At other times,		in the cells of animals, but not in those of the higher plants. The centrosome becomes prominent when a cell is about to divide. At other times,
	in many kinds of cells, it has been found as a minute granule which may		in many kinds of cells, it has been found as a minute granule which may
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	consists of protoplasm, nucleus, and centrosome.		consists of protoplasm, nucleus, and centrosome.

	==Protoplasm==		===Protoplasm===
	Protoplasm is the living substance of which cells are composed.		Protoplasm is the living substance of which cells are composed. More specifically the term is applied to this living substance exclusive of the nucleus, or to the corresponding dead material, provided that death
	More specifically the term is applied to this living substance exclusive of
	the nucleus, or to the corresponding dead material, provided that death
	has not changed its physical properties. It has been proposed to substitute		has not changed its physical properties. It has been proposed to substitute
	the name cytoplasm for protoplasm in the restricted and earlier sense of		the name cytoplasm for protoplasm in the restricted and earlier sense of
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			Fig. 4.Vacl-oi. in Young Fat cells.

	~~HISTOLOGY~~


	~~Fig. 4.Vacl-oi.^ in Young~~

	~~Fat cells.~~



	~~Nuelem. Nucleolus,~~




	~~Cs\|i9ttk* Caiialicijli.~~

	~~%N>KGtUM> IH A KEttVe~~



	~~RetkulÂ»r upparatiis,~~

	Fig 6, ReTictijLAM Nktwork iN A NsKVh CmLL, C After		Fig 6, ReTictijLAM Nktwork iN A NsKVh CmLL, C After
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	3* Vacuoles. Well defined, round spaces,		3. Vacuoles. Well defined, round spaces,
	apparently empty, may occur in the protoplasm		apparently empty, may occur in the protoplasm
	due to the formation of droplets of fat or of watery		due to the formation of droplets of fat or of watery
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	paranuclei are still obscure.		paranuclei are still obscure.

	==Nucleus==		===Nucleus===
	The nucleus (Latin, nuclms, 'the kernel of a nut"; Greek, ^i^jov, "a nut') is a well defined,		The nucleus (Latin, nuclms, 'the kernel of a nut"; Greek, ^i^jov, "a nut') is a well defined,

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	bone cells.		bone cells.

	==Centrosome==		===Centrosome===

	The centrosome is a minute body consisting of a homogeneous or sometimes reticular mass, the centroplasm, which contains a much smaller body, the ceniriole. Such centrosomes have been observed in the invertebrate animals. The cells of vertebrates are not regarded as favorable		The centrosome is a minute body consisting of a homogeneous or sometimes reticular mass, the centroplasm, which contains a much smaller body, the ceniriole. Such centrosomes have been observed in the invertebrate animals. The cells of vertebrates are not regarded as favorable
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	delay.		delay.

	==Cell Wall==		===Cell Wall===
			:''Online editor - "Cell wall" is a historic term for the cell membrane and the term is now used to describe non-membrane structures in outside plant cells and outside bacterial membranes.''

	A cell wall or cell membrane is an independent membranous layer		A cell wall or cell membrane is an independent membranous layer covering a cell and being clearly distinct from the underlying protoplasm. It is not an essential constituent of a cell. Often it is lacking, and when present it is either a modification or a secretion of the peripheral protoplasm. If the membrane surrounds the cell on all sides it is called a pellicula;
	covering a cell and being clearly distinct from the underlying protoplasm.		if it is on only one side, covering the free surface, it is a cuiicula. (The former term is seldom used.) Cells may unite with one another by protoplasmic processes of varying length and width, thus forming cellular networks; or they may completely fuse so that their nuclei appear irregularly distributed through a single mass of protoplasm. Such a formation
	It is not an essential constituent of a cell. Often it is lacking, and when
	present it is either a modification or a secretion of the peripheral protoplasm.
	If the membrane surrounds the cell on all sides it is called a pellicula;
	if it is on only one side, covering the free surface, it is a cuiicula. (The
	former term is seldom used.) Cells may unite with one another by protoplasmic processes of varying length and width, thus forming cellular
	networks; or they may completely fuse so that their nuclei appear irregularly distributed through a single mass of protoplasm. Such a formation
	is a syncytium [plasmodium]. This name is applied also to such structures		is a syncytium [plasmodium]. This name is applied also to such structures
	as the striated muscle fiber, due not to the fusion of cells but to the multipUcation of nuclei in an undivided mass of protoplasm.		as the striated muscle fiber, due not to the fusion of cells but to the multipUcation of nuclei in an undivided mass of protoplasm.
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	occurrence will be described presently.		occurrence will be described presently.

	==Amoeboid Motion==		===Amoeboid Motion===

	The imicellular animal, Amoeba, exhibits a type of motility known		The imicellular animal, Amoeba, exhibits a type of motility known
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	be examining.		be examining.

	==Mitosis==		===Mitosis===

	Prophase, The centrosome and nucleus approach one another until		Prophase, The centrosome and nucleus approach one another until
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	Loose monospireme		Loose monospireme

	(viewed from above ~~â€”~~		(viewed from above

	Â». g., from the pole).		Â». g., from the pole).
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	Fig. i6.~~â€”~~ Mitosks in Human Cancer Cells. (From Wilson, after Galeotti.)		Fig. 16. Mitosks in Human Cancer Cells. (From Wilson, after Galeotti.)
	a. Asymmetrical mitosis with unequal distribution of chromatin; bÂ» tripolar mitosis; c* quadripolar mitosis.		a. Asymmetrical mitosis with unequal distribution of chromatin; bÂ» tripolar mitosis; c* quadripolar mitosis.

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			==Amitosis=
	==Amitosis==

	Amitosis or direct cell division takes place without spindle formation		Amitosis or direct cell division takes place without spindle formation
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	Division of the nucleolus. Division of the nucleus.		Division of the nucleolus. Division of the nucleus.

	Fig. 17.~~â€”~~ Amitosis in Epithelial Cells from the Bladder of a Mouse. X560.		Fig. 17. Amitosis in Epithelial Cells from the Bladder of a Mouse. X560.

	tissues where it has been interpreted both as a result of injury and as		tissues where it has been interpreted both as a result of injury and as
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	amitosis is a common and normal process.		amitosis is a common and normal process.

	~~CYTOMORPHOSIS.~~		==Cytomorphosis==

	Cytomorphosis is a comprehensive term for the structural modifications		Cytomorphosis is a comprehensive term for the structural modifications which cells or successive generations of cells may undergo from their
	which cells or successive generations of cells may undergo from their
	origin to their final destruction. It implies that the life of a cell is limited,		origin to their final destruction. It implies that the life of a cell is limited,
	and that during its life it may change in structure by becoming dijferentiated^		and that during its life it may change in structure by becoming dijferentiated^

Z8600021: Created page with "{{Lewis1906 header}} =I. Cytology= ==The Cell== Since 1839 it has been known that all plants and animals are composed of small structural elements called cells (Latin, cel..."

2015-02-05T23:25:16Z

Created page with "{{Lewis1906 header}} =I. Cytology= ==The Cell== Since 1839 it has been known that all plants and animals are composed of small structural elements called cells (Latin, cel..."

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