Cells and TissuesCells and Tissues
Cells and TissuesCells and Tissues
Carry out all chemical activities needed to Carry out all chemical activities needed to sustain lifesustain life
Cells are the building blocks of all living Cells are the building blocks of all living thingsthings
Tissues are groups of cells that are similar Tissues are groups of cells that are similar in structure and functionin structure and function
For Example: muscle tissueFor Example: muscle tissue
Anatomy of the CellAnatomy of the Cell
Cells are not all the sameCells are not all the sameAll cells share general structuresAll cells share general structuresAll cells have three main regionsAll cells have three main regions
NucleusNucleusCytosol (cytoplasm)Cytosol (cytoplasm)Plasma membranePlasma membrane
The NucleusThe Nucleus
Control center of the cellControl center of the cellContains genetic material (DNA)Contains genetic material (DNA)
Three regionsThree regionsNuclear envelopeNuclear envelope (membrane) (membrane)NucleolusNucleolus (plural nucleoli) (plural nucleoli)ChromatinChromatin (DNA coiled around protein – (DNA coiled around protein –
protein acts as support for fragile DNA)protein acts as support for fragile DNA)
The NucleusThe Nucleus
The Nucleus continued…The Nucleus continued…Nuclear envelopeNuclear envelope ( or ( or
nuclear membrane) nuclear membrane) Barrier of the nucleus; Barrier of the nucleus;
separates in from outseparates in from outConsists of a double Consists of a double
membranemembraneContains nuclear pores Contains nuclear pores
that allow for exchange that allow for exchange of material with the rest of material with the rest of the cellof the cell
The Nucleus continued….The Nucleus continued….
NucleoliNucleoli Nucleus contains one Nucleus contains one
or more nucleolior more nucleoli Sites of ribosome Sites of ribosome
productionproduction Ribosomes move into Ribosomes move into
the cytoplasm through the cytoplasm through nuclear poresnuclear pores
NucleolusNucleolus
The Nucleus continued….The Nucleus continued….ChromatinChromatin
Composed of DNA and proteinComposed of DNA and protein Present when the cell is not dividingPresent when the cell is not dividing Scattered throughout the nucleusScattered throughout the nucleus Coils and shortens to form chromosomes when the cell Coils and shortens to form chromosomes when the cell
divides (protects fragile DNA during cell separation)divides (protects fragile DNA during cell separation)
Plasma MembranePlasma MembraneBarrier for cell contentsBarrier for cell contentsControls what exits and enters the cell through Controls what exits and enters the cell through
osmosis and diffusionosmosis and diffusionAlso contains proteins, cholesterol, and Also contains proteins, cholesterol, and
glycoproteins (proteins with sugar attached)glycoproteins (proteins with sugar attached)
Plasma MembranePlasma Membrane
Membrane StructurePLAY
Plasma Membrane Plasma Membrane SpecializationsSpecializations
MicrovilliMicrovilli Finger-like projections Finger-like projections
that increase surface that increase surface area for absorptionarea for absorption
Microvilli are present Microvilli are present in our intestines; helps in our intestines; helps absorp nutrients and absorp nutrients and water we consume by water we consume by eatingeating
Cytoplasm or CytosolCytoplasm or Cytosol
Cytoplasm is the material outside the Cytoplasm is the material outside the nucleus and inside the plasma membrane nucleus and inside the plasma membrane
It’s the fluid that all organelles are It’s the fluid that all organelles are suspended insuspended in
CytoplasmCytoplasm
Contains three major elementsContains three major elementsCytosolCytosol
Fluid that suspends other elements (jello)Fluid that suspends other elements (jello)
OrganellesOrganelles machinery of the cell machinery of the cell ““Little organs” that perform functions for the cellLittle organs” that perform functions for the cell
InclusionsInclusions Chemical substances such as stored nutrients or Chemical substances such as stored nutrients or
cell products like wastecell products like waste
Cytoplasmic OrganellesCytoplasmic Organelles
Cytoplasmic OrganellesCytoplasmic OrganellesMitochondriaMitochondria
““Powerhouses” of the cellPowerhouses” of the cell Change shape continuouslyChange shape continuously Carry out reactions where oxygen is used to break Carry out reactions where oxygen is used to break
down fooddown food Provides energy for cellProvides energy for cell
Cytoplasmic OrganellesCytoplasmic OrganellesRibosomesRibosomes
Made of protein and RNAMade of protein and RNASites of protein productionSites of protein productionFound at two locationsFound at two locations
Free in the cytoplasmFree in the cytoplasm On Rough EROn Rough ER
Cytoplasmic OrganellesCytoplasmic Organelles
Endoplasmic reticulum (ER)Endoplasmic reticulum (ER)Fluid-filled tubes for carrying substancesFluid-filled tubes for carrying substancesTwo types of ERTwo types of ER
Rough endoplasmic reticulumRough endoplasmic reticulum Covered with ribosomesCovered with ribosomes Makes proteins Makes proteins
Smooth endoplasmic reticulumSmooth endoplasmic reticulum Functions in lipid and steroid production and also Functions in lipid and steroid production and also
detoxifies drugs and pesticides that invade the celldetoxifies drugs and pesticides that invade the cell
Rough Endoplasmic Rough Endoplasmic ReticulumReticulum
Ribosome
Protein
Protein insidetransport vesicle
Transportvesicle buds off
mRNA
Rough ER
As the protein is synthesizedon the ribosome, it migratesinto the rough ER cistern.
In the cistern, the protein foldsinto its functional shape. Shortsugar chains may be attachedto the protein (forming aglycoprotein).
The protein is packaged in atiny membranous sac called atransport vesicle.
The transport vesicle buds fromthe rough ER and travels to theGolgi apparatus for furtherprocessing or goes directly tothe plasma membrane where itscontents are secreted.
Cytoplasmic OrganellesCytoplasmic Organelles
Golgi apparatusGolgi apparatus Modifies and packages Modifies and packages
proteinsproteins Produces different types of Produces different types of
packagespackages Secretory vesiclesSecretory vesicles Cell membrane componentsCell membrane components LysosomesLysosomes
Extracellular fluid
Plasma membrane
Golgi vesicle containingmembrane componentsfuses with the plasmamembrane
Golgi vesicle containingdigestive enzymesbecomes a lysosome
Proteins in cisterna
Lysosome fuses withingested substances
Membrane
Transportvesicle
Pathway 3
Pathway 2
Secretory vesicles Pathway 1
Golgiapparatus
Golgi vesicle containingproteins to be secretedbecomes a secretoryvesicle
Cisterna
Rough ER
Proteins
Secretion byexocytosis
LysosomesLysosomes Contain enzymes that digest worn-out or nonusable Contain enzymes that digest worn-out or nonusable
materials within the cellmaterials within the cell
Cytoplasmic OrganellesCytoplasmic OrganellesPeroxisomesPeroxisomes
Membranous sacs of Membranous sacs of oxidase enzymesoxidase enzymes
Detoxify harmful Detoxify harmful substances such as substances such as alcohol, hydrogen alcohol, hydrogen peroxide and peroxide and formaldehydeformaldehyde
Break down free Break down free radicals (highly radicals (highly reactive chemicals)reactive chemicals)
Network of protein structures that extend Network of protein structures that extend throughout the cytoplasmthroughout the cytoplasm
Provides the cell with an internal framework Provides the cell with an internal framework which keeps the cell 3-Dimensionalwhich keeps the cell 3-Dimensional
CytoskeletonCytoskeleton
CellularCellular ProjectionsProjectionsNot found in all cellsNot found in all cellsUsed for movementUsed for movement
Cilia move materials Cilia move materials across the cell surfaceacross the cell surface
Located in the Located in the respiratory system to respiratory system to move mucus move mucus
Flagella propel the cell Flagella propel the cell The only flagellated The only flagellated
cell in the human cell in the human body is spermbody is sperm
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