THE CELL THE CELL “ “ The smallest unit that The smallest unit that can carry out all the can carry out all the processes of life.” processes of life.” Why are they important? Click the pic
Dec 27, 2015
THE CELLTHE CELL““The smallest unit that can carry The smallest unit that can carry
out all the processes of life.”out all the processes of life.”
Why are they important?
Click the pic
Discovery of the CellDiscovery of the Cell
ROBERT HOOKEROBERT HOOKE First to observe cells.First to observe cells. He examined cork He examined cork
cells.cells. ““These little boxes These little boxes
reminded him of the reminded him of the small rooms in which small rooms in which monks lived, so he monks lived, so he called them cells.”called them cells.”
Discovery of the CellDiscovery of the Cell
Anton van LeeuwenhoekAnton van Leeuwenhoek – First person – First person to examine living cells & father of to examine living cells & father of microscopymicroscopy
Matthias SchleidenMatthias Schleiden – “All plants are – “All plants are composed of cells.”composed of cells.”
Theodore SchwannTheodore Schwann – “All animals are – “All animals are composed of cells.”composed of cells.”
Rudolf VirchowRudolf Virchow – “All cells come from – “All cells come from existing cells.”existing cells.”
The Cell TheoryThe Cell Theory
Schleiden, Schwann, & VirchowSchleiden, Schwann, & Virchow All living things are composed of one All living things are composed of one
or more cells.or more cells. Cells are organisms’ basic units of Cells are organisms’ basic units of
structure & function.structure & function. Cells come from existing cells.Cells come from existing cells.
CELL DIVERSITYCELL DIVERSITY
1. Size1. Size Cells range in size Cells range in size
from .2 um to 2 m.from .2 um to 2 m. Average plant & Average plant &
animal cells are 10 to animal cells are 10 to 50 um in diameter.50 um in diameter.
2. Shape2. Shape Cuboidal & spherical.Cuboidal & spherical.
3. Internal Organization3. Internal Organization Different OrganellesDifferent Organelles
TYPES OF CELLSTYPES OF CELLS EukaryotesEukaryotes – –
Contains a nucleus Contains a nucleus and membrane-bound and membrane-bound organelles.organelles.
ProkaryotesProkaryotes – Lacks – Lacks a nucleus. (bacteria)a nucleus. (bacteria)
OrganelleOrganelle – A cell – A cell component that component that performs specific performs specific functions in the cell.functions in the cell.
ORGANELLESORGANELLES
NucleusNucleus Cell MembraneCell Membrane CytoplasmCytoplasm RibosomesRibosomes Rough Endoplasmic Rough Endoplasmic
ReticulumReticulum Smooth Endoplasmic Smooth Endoplasmic
ReticulumReticulum
Golgi ApparatusGolgi Apparatus MitochondriaMitochondria LysosomesLysosomes Cytoskeleton - Cytoskeleton -
Microtubules & Microtubules & MicrofilamentsMicrofilaments
CiliaCilia FlagellaFlagella
The NucleusThe Nucleus
Directs activities of Directs activities of the cell.the cell.
Contains DNA.Contains DNA. NucleolusNucleolus – synthesis – synthesis
of ribosomes.of ribosomes. Nuclear poresNuclear pores Nuclear envelopeNuclear envelope NucleoplasmNucleoplasm
DNADNA
Deoxyribonucleic acidDeoxyribonucleic acid Encodes information Encodes information
important for the important for the synthesis of proteins.synthesis of proteins.
CYTOPLASMCYTOPLASM
Contains various Contains various organs in the cellorgans in the cell
Gelatin-like fluid Gelatin-like fluid called called cytosolcytosol which which has dissolved salts, has dissolved salts, minerals, and organic minerals, and organic moleculesmolecules
CELL MEMBRANECELL MEMBRANE
Made of lipids & Made of lipids & proteins.proteins.
Provides shape & Provides shape & flexibility.flexibility.
Selectively Selectively PermeablePermeable - a - a complex barrier that complex barrier that keeps out some keeps out some molecules & allows molecules & allows others through.others through.
RIBOSOMESRIBOSOMES
Carry out protein Carry out protein synthesis.synthesis.
Attached ribosomesAttached ribosomes - - attached to Rough attached to Rough ER; produce proteins ER; produce proteins to be exported by the to be exported by the cell.cell.
Free ribosomesFree ribosomes - - produce proteins for produce proteins for the cell.the cell.
ENDOPLASMIC ENDOPLASMIC RETICULUMRETICULUM
Rough Endoplasmic Rough Endoplasmic ReticulumReticulum - (ER) - A - (ER) - A membrane system membrane system covered with covered with ribosomes; aids in ribosomes; aids in protein synthesis.protein synthesis.
Smooth ERSmooth ER - Few or - Few or no ribosomes; no ribosomes; intracellular pathway intracellular pathway for proteins.for proteins.
GOLGIGOLGI APPARATUSAPPARATUS
System of System of membranes.membranes.
Processing, Processing, packaging, & packaging, & secreting organelle secreting organelle of the cell.of the cell.
MITOCHONDRIAMITOCHONDRIA
““Powerhouse of the Powerhouse of the cell.”cell.”
Carries out cellular Carries out cellular respiration.respiration.
LYSOSOMESLYSOSOMES
Contains digestive Contains digestive enzymes.enzymes.
Digests food & Digests food & disease-causing disease-causing bacteria.bacteria.
CYTOSKELETONCYTOSKELETON
Provides a structural Provides a structural framework for the cell.framework for the cell.
MicrotubulesMicrotubules - long, - long, slender protein tubesslender protein tubes
MicrofilamentsMicrofilaments - fine - fine protein threads.protein threads.
CILIA & FLAGELLACILIA & FLAGELLA
Function in movement.Function in movement. Composed of proteins.Composed of proteins. CiliaCilia - small & hair-like; covers entire - small & hair-like; covers entire
surface of the cell.surface of the cell. FlagellaFlagella - long & slender; found singly or in - long & slender; found singly or in
pairs.pairs.
VACUOLESVACUOLES
Store substances Store substances inside the cell.inside the cell.
Plant cells have large Plant cells have large central vacuoles.central vacuoles.
CENTRIOLESCENTRIOLES
Structure that Structure that appears during appears during animal cell divisionanimal cell division
CELL WALLCELL WALL
Only in plant cellsOnly in plant cells Lies outside the cell Lies outside the cell
membranemembrane Supports and protects Supports and protects
the plantthe plant
PLASTIDSPLASTIDS
Convert solar energy Convert solar energy into chemical energy.into chemical energy.
ChloroplastChloroplast - contain - contain green pigmentsgreen pigments
LeucoplastLeucoplast - store - store food, such as food, such as starches.starches.
ChromoplastChromoplast - - synthesize & store synthesize & store other pigments.other pigments.
Plant cells only!!Plant cells only!!
CHLOROPLASTSCHLOROPLASTS
Found in plant cells Found in plant cells onlyonly
Where the energy of Where the energy of sunlight is converted sunlight is converted into chemical energy into chemical energy during photosynthesisduring photosynthesis
Contain green Contain green pigment called pigment called chlorophyllchlorophyll
DIFFERENCES BETWEEN DIFFERENCES BETWEEN PLANT & ANIMAL CELLSPLANT & ANIMAL CELLS
ANIMAL CELLSANIMAL CELLS CentriolesCentrioles Small vacuolesSmall vacuoles
PLANT CELLSPLANT CELLS PlastidsPlastids Large central vacuoleLarge central vacuole Cell WallCell Wall