cytology morphology of cells lect pt.1

what is the cell?

• main structural, functional and metabolic unit of the organism

• A biosystem – open

• self regulating, self reproducing

outline the cell theory (5)

• cell elementary unit of the living body

• all organisms made of cells

• all cells have similar organisation

• reproduce by division

• linked together and influence eachother

glycocalyx

gel-like dense meshwork surrounding cells

hyaloplasm

clear fluid portion of cytoplasm

cytoplasm

semi-fluid portion of cytoplasm

size of cell

6-60 mcm

oocyte size

200 um

shapes of cells

flatten

Cuboidal

cylindrical

Polygonal

Stellate (like stars)

Pear

Pyramidal

Spindle

morphology

morphology describes the shape, structure, form, and size of cells

plasmalemma

less common term meaning plasma membrane

glycocalyx

a network of polysaccharides that project from cellular surfaces of bacteria

cytoplasm

material living inside cell excluding nucleus so includes cytosol and other materials

cytosol/hyaloplasm

gel-like substance within the cell that surround the cells organelles

obliged cell examples by membrane

• endoplasmic reticulum

• mitochondria

• peroxisomes

• lysosomes

• coated vesicles

non membrane

• ribosomes

• cytocentre

• microfilaments (myofibril, neurofibril, flagella)

cell inclusions

• glycogen

• lipid drops

• protein granules

• pigments

• crystals

label

what are cells made of?

water - 90%

organic substances :

• monomer : amino acids, glycerol, monosaccharides, nucleotides

• polymer : proteins, lipids, DNA, RNA

how thick plasma membrane?

8-10 nm thick

sandwich model

Davson & Danielli

• 2 protein layers

• 1 lipid bilayer between

• outer is hydrophilic

• inner hydrophobic

fluid model

Singer & Nickleson

• 2 lipid layers with globular proteins attached

• integral protein - attached to both lipid layers

• semi-integral protein - attached to one of the lipid layers

• peripheral proteins - attached to the head of the lipid molecules

• 65% lipid

• 35% proetin

• 1% carb

describe integral, semi-integral and peripheral proteins

• integral protein - attached to both lipid layers

• semi-integral protein - attached to one of the lipid layers

• peripheral proteins - attached to the head of the lipid molecules

• COOH and PO4 ends

phospholipids

most amount of lipids in the elementary membrane

• make the lipid bilayer

• hydrophilic head

• hydrophobic tail

cholesterol

inside the lipid bilayer

C H O

glycolipids

lipids with sugar

outer layer of the membrane

fo interaction between cells and cell-matrix

make the outer surface of the membrane negatively charged

glycoproteins

protein with sugar

outer layer of membrane

cell receptors

located outer part of membrane

attached to specific molecules (ligands)

recognise the proper molecule

transport proteins

• for transport of amino acids, monosaccharides, ions

• connecsones - transport of ions and low molecule substances

attaching proteins

• for attaching cellsone to another

• Ca ++ dependent

• Ca ++ independent

tranductor proteins

between cell receptors and adynilate cyclase (secondary tranductor)

enzymes

more than 30

ATP-asa, AP-asa, RNC-asa, cAMP-asa

ways of transmembrane transport

Passive- without energy supply and conductor (transport proteins)

• Diffusion

• Filtration

• Оsmosis

Аctive transport – K+-Na+ pump spdium potassiom ion pump 2K in 3Na out

• energy supply - АТP

• conductor (transport proteins)

• against the gradient

• Transport with the help of transport proteins (permiases) which are electrically charged

cytosis

transport of large molecules

connexones

transport ions and low molecule substances

endocytosis types

phagocytosis - solid particles

pinocytosis - fluids

• fluid-phase pinocytosis - without coated vesicles

• receptor-mediated endocytosis - with coated vesicles

• protein clathrin - clathrin coated pit

glycokyte rough structure

cytosol

• cytoplasm without the organelles

• made of water, ions, proteins, glucose, ATP

compartmentalization

different parts in the cell surrounded by biomembranes possess different chemicals, metabolism

endoplasmic reticulum (microscope, type, component, origin)

• seen with ELECTRON microscope only

• membrane bound organelle made of parallel cysternae

• 50% of membrane in the cell, elementary membrane

• made of 60% protein 40% lipid

• originate from plasmalema (cell membrane), nuclear membrane

• smooth and rough type

smooth ER (size, functions)

morphology

• system of cysternae (7nm)

• tubules packed by smooth membrane

function

• synthesis of lipid, steroid, glycogen, glucoaminoglycanes

• transport of substances in the cell

• depot of Ca ions (muscle contraction)

• production of Cl- ions for HCL in the parietal cells of the stomach

• detoxification

rough ER (size, localisation)

morphology

• membrane bound cysternae 10 nm wide

• ribosomes on outer

• linked to nuclear membrane

• stained with basic dye basophilia becaus eof ribosomes/RNA

localisation

• in basic part, as nissl granulation in the neurons

golgi apparatus (microscope, morphology, location)

• can be seen with light microscope AgNO3 impregnation

• network of cysternae, vacuoles and vesicles

• near the nucleus, 50-200nm wide

• vacuoles - concentration and transport of the proteins

• vesicles - transport of proteins

• proximal - cis zone of production

• distal - trans zone of maturation

mitochondria (function, morphology, microscope)

• has enzymes for Kreb’s cycle for ATP production, give energy to cell

• light microscope - rods and dots using iron-hematoxylin

• electron microscope - membrane bound organelles outer and inner

• outer is smooth inner is folded cristae

• enzymes for Krebs cycle

• intermembranous space, inner mitochondreal space

• matrix - Ca2+, PO42+, DNA - self division

difference between apocrine, melocrin and holocrine

Definition:These are three types of glandular secretion methods.

apocrine - releases its product by budding off a portion of the cell membrane, allowing the cell to remain intact

melocrine - secretes products directly through the cell membrane without losing any cellular materia

holocrine - involves the entire cell disintegrating to release its contents, resulting in cell death