HISTOLOGY LECTURE 1 : Cytology I

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today's lecture is about some aspects of

cell structure some organal and

inclusions before we are going to

discuss this topic I would like to ask

you to study these textbooks for the

lessons we are going to study with you

stain slides and uh the subject of study

is a micro preparation or stain slid or

histological specimen we are studying

our slides with the help of light

microscope which is composed of

mechanical and Optical Parts Optical

components consist of three systems of

lenses condenser objective and eyepiece

the condenser collects and focuses light

producing a core of light that

illuminates the object the objective

lens enlarges and projects the

illuminated image of the object in the

direction of the eyepiece the eyepiece

magnifies this image and projects it

onto the retina the total magnification

is obtained by multiplying the

magnifying power of the objective and ey

piece for our preparations we use

histological stains the example of basic

stain is

hematoxilin it is a nucleus stain and it

is of dark blue color it gives nucleus a

blue color because there are D deoxy

ribonucleic acids in the

nucleus you must learn by heart two

terms basophilia and basophilic

structure so what is

basophilia property of the structure

coloring in the blue is called

basophilia and the structure coloring in

the Blue by basic D is called basophilic

in this diagram we can see with you

basophilic nuclei as Dain is eosine it

is of red color eosine color cytoplasm

in the pink because there are proteins

in the cytoplasm property of the

structure coloring in the pink is called

acidophilia the structure coloring in

the Pink by acidic stain is called

acidophilic structure we can see here

cytoplasm red color and it is

acidophilic structure we can use

selective stains for example for fats

orme it is black color it gives fats

black color lipids we can see in the

micro preparation liver cells with the

inclusions of lipes they stained by

osmium into black color one more example

it is Sudan 3 it gives orange color to

fat for the glycogen we can use Carmin

of best and it colors glycogen into

bright red color with raspberry shade in

the liver cells we can can see with you

inclusions of glycogen which are stained

by Carmino best cell definition cell is

the Primitive alive system which consist

of the nucleus the cytoplasm and the

plasma Lima and it is the base of the

development structure and function of

the organism cell consist of a nucleus

cytoplasm and organel and cell membrane

here we discuss with View organal and we

must give definition to the organal

organal are the constant components of

the cytoplasm which have definite

structure and definite function we need

to classify organel we can use some

classifications the first classification

subdivide organal into membranous and

non-membranous organal there are five

membranous organal endoplasmic reticulum

gold apparatus lomes peroxy isomes and

mitochondria non-membranous organal they

are ribosomes cell center and elements

of

cytoskeleton one more classification

subdivide organal into common and

special common they are endoplasmic

reticulum G apparatus cell center lomes

peroxisomes mitochondria and ribosomes

and special which are need to for the

cell for special function they are Celia

micro and

flagel here we can see with you

endoplasmic reticulum two types ra

endoplasmic reticulum and smooth

endoplasmic

reticulum granula or rough endoplasmic

reticulum it is membranous organal it is

formed by systems tubules and vesicles

and it is covered with ribosomes the

main function is protein synthesis and

transport of these proteins if rough

endoplasmic reticulum is good developed

then this cell produces proteins for the

export and enzymes proteins and they are

active

synthesized a granal endoplasmic

reticulum is membranous organal which is

formed by tubules toems vesicles which

are surrounded by membranes and they are

not covered by ribosomes the main

function of a granola endoplasmic

reticulum synthesis of carbohydrate

lipids and steroid hormones

detoxification of toxic substances

especially within liver cells deposition

of calcium ions especially for muscle

tissue transport of synthesized

substances gold G complex can be stained

by silver impregnation and the St

clusters form

diome location of gold complex near the

nucleus main function fun of G complex

accumulation of synthesized products

modification of biomolecules formation

secretory vesicles transport of these

vesicles and formation of lomes lomes

they membranous organal to they

spherical in shape they contain lots of

enzymes at about 40 hras

enzymes and there are some types of

lomes primary lomes they are formed just

within G apparatus when primary lomes

fuse with phagosome they form

fomes and it is secondary liome if

primary liome fuses with the organel it

is called outer

foso after process of digestion residual

bodies are formed which have got

liposin the main functions of lomes

breaking down most biological me

molecules and to NOA of cytoplasmic

organel in this electron microphotograph

we can see lysosomes are near the gold

operatus peroxisomes membranous organal

they spherical inshape they contain

enzymes for metabolic reactions for

oxidation and detoxification of specific

organic substances catales breaks down

the hydrogen peroxide resulting from

those reaction enzymes inactivate toxic

molecules for example medical drugs

abundant peroxisomes in liver and kidney

cell in this electron microphotograph we

can see with VI per exosome with the

crystalloid center mitochondria double

membrane bound organal contains DNA for

mitochondrial proteins and a MAA enzyme

which is called suxin

dehydrogenase the main function of my

mitochondria syn synthesize ATP during

aerobic cellular respiration by

digestion of fuel molecules in the

presence of

oxygen ribosomes ribosomes nonmembranous

organal they consist of proteins and

ribosomal RNA they have got two subunits

a large and small subunits and they may

be bound to membrane or free and then

they can form po

ribosomes the main functions of

ribosomes bound ribosomes they take part

within protein synthesis for expert

threee ribosomes they produce proteins

which are necessary for the cell

elements of

cytoskeleton they are microtubules

microfilaments and intermediate

filaments microtubules form a part of

mitotic spindle of the cell division in

the inter face cell microtubules form

the

cytoskeleton they are included in

flagellum Celia and

cental microt tual external diameter is

about 25 nanom inner diameter is about

15

nanom the W thickness is at about 5

nanom microtubules include protein

tubulin the tubulin forms Rings the

Rings are stacked over one and another

to form

protofilaments every microt tual

includes 1 protofilaments a microt cell

formation is induced by the matal

central inside the hyaloplasm if the

cell temperature is subnormal a microt

tubal cell formation is stopped all

other microtubules are destroyed and the

shape of the cell becomes irregular the

main functions of microtubules

microtubules form the cyto skeleton of

the cell and keep the cell shape

microtubules take part in movement of

Celia and flagel there is a special

protein kisine in the cell and this

protein moves vesicles mitochondria and

other substances alone microtubes in the

cell

cytoplasm

microfilaments consist of proteins such

as etine for example myosin a

microfilament is at the about 6 nanom in

diameter microfilaments Li deep to a

cell membrane and form submembrane layer

or cortical layer of the cell if

microfilaments of submembrane layer

contract a cell membrane is inated by

phagocytosis pinocytosis and cell

division during cyto Kinesis

microfilaments take part in pseudopod

formation during cell movement the

functional significance of microfilament

they form

cytoskeleton they take part in

intracellular

movement microfilaments take part in

extracellular movement of the cell

intermediate filaments consist of

special protein intermediate filaments

have rodlike shape these filaments are

10 nanom in diameter different tissue

cells have different special proteins

intermediate filaments of epithel cells

include protein keratin intermediate

filaments of connective tissue cells

include protein ventin and intermediate

filaments of smooth muscle cell include

protein DM so they are included into the

cyto skeleton tumor of tissues may be

recognized with the help of intermediate

proteins if a tumor includes keratin the

tumor is developed from epithelial

tissue for example in this

microphotograph we can see with you

cytoskeleton in green color there are

microt tubules and within orange color

we can see with you micro filaments cell

center or centrosome it is microt tual

organizing Center it consists of pair of

centrioles and each cental has got nine

triat of microt tubules and function of

the cell center organizes micro tubules

and formation of the mitotic spinder

Celia Celia consist of exm and Basel

body exm is formed by microtubes which

are organized in nine duplet and two

Central

microtubules Basel body is formed by

microtubules too but they are organized

into nine replace of microt tuul the

main function of Celia are movement of

substances over the cell

surface here we can see with you micro

preparation of pseud certified sated

epithelium with the Celia on the epical

surface of EP epithelial cells and

electron micr photograph which shows you

exm and Basel bodies of Celia and this

micro preparation of Pudo certifi

related epithelium in low magnification

on the iCal surface number three shows

you Celia micro they are thin membrane

fors and they project from the free cell

surface they are supported by

microfilaments some epithelia have only

a small number of irregular

micro but we can find regular micro they

have got the same height and they are

called straight border or brush border

for example such a structures we can

find within small intestine within

proximal renal tubil here you can see

vas of small intestine and we can see

that surface of the vas is covered by

brush border number three the function

main function is necessary for

increasing of membrane surface for

absorption inclusions definition of

inclusions they are non constant

components of the cytoplasm and their

presence depends on the cell metabolism

we can classify inclusions into four

groups trophic inclusions for example

like in these

microphotographs we can see glycogen

inclusions and lipid inclusions within

liver cells secretory inclusions

excretory inclusions and pigment

inclusions in this electron micrograph

we can see with you secretory inclusions

uh in the epical part of the go cells

and preparation of melanocytes with

pigment inclusions pigment

melanin intercellular Junctions or

contacts between AD joint cells we can

classify in two groups simple Junctions

and complex J Junctions complex

Junctions include auding Junctions or

Tide Junctions which provide a close

Association of plasma membranes of the

cells which I imp

for ions and

macromolecules Anor injunctions adhesive

sports or they are called

desmosomes between the epithelial cells

for example hemidesmosomes between the

epithelial cell and Basel membrane and

adhesive bels and communicating

Junctions Gap Junctions or

nexuses they are necessary for passing

of ions and small molecules synapses

they transfer no impulse from one neuron

to another with the help of

mediators thank you for your attention

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