Prokaryotic CellCellular Structure and FunctionThey do not contain membrane-bound organellesCell Discovery and TheorySteven P. LynchSection 1Prokaryotes are single-celled organisms that lack a nucleus and other internal compartments

Prokaryotic CellProkaryotic cells includes all bacteriaProkaryotes contain only the following structures:

Cell wall (peptidoglycan)Plasma membraneGenetic material as a single circular molecule of DNARibosomesCytoplasmPlasmid (Small circular piece of DNA that only some bacteria possess)

Cellular Structure and FunctionSection 1

Prokaryotic CellCellular Structure and FunctionCell Discovery and TheorySection 1

Eukaryotic CellMore complex structure than prokaryotesCellular Structure and FunctionIn addition to the prokaryotic structures, eukaryotes also have membrane bound organelles, including a nucleusSection 1

Cellular Structure and FunctionCell Discovery and TheorySection 1

Comparing Prokaryotic and Eukaryotic CellsCellular Structure and FunctionCell Discovery and TheoryTheSection 1

Plasma MembraneThin, flexible boundary between the cell and its environmentThe Plasma MembraneCellular Structure and FunctionAllows nutrients into the cellAllows waste to leave the cellSection 1

Selective PermeabilityCellular Structure and FunctionThe plasma membrane controls the movement of substances into and out of the cell.The plasma membrane is selectively permeable, meaning it chooses what enters and leaves the cellThe Plasma MembraneSection 2

The plasma membrane is composed of the phospholipid bilayer.Cellular Structure and FunctionA phospholipid molecule is composed of a glycerol backbone, two fatty acid chains, and a phosphate group.The Plasma MembraneSection 2

Cellular Structure and FunctionThe Plasma MembraneSection 2

Fluid Mosaic ModelCellular Structure and FunctionThe phospholipid bilayer allows other molecules to float in the membrane.Other ComponentsProteinsCholesterolCarbohydratesThe Plasma MembraneSection 2

ProteinsCellular Structure and FunctionTransmit signals inside the cellAct as a support structureProvide pathways for substances to enter and leaveThe Plasma MembraneSection 2

Cellular Structure and FunctionSection 2

Cellular Structure and FunctionPlant and Animal Cell StructuresStructures and OrganellesSection 3Organelles are bodies within the cytoplasm that serve to physically separate the various metabolic reactions that occur within the cells1. Nucleus7. Mitochondria2. Ribosomes8. Chloroplasts3. Endoplasmic reticulum9. Cytoskeleton4. Golgi Apparatus10. Flagella & Cilia5. Lysosomes11. Centrioles6. Peroxisomes12. Vacuoles & Vesicles

Cellular Structure and FunctionStructures and OrganellesSection 3

Cellular Structure and FunctionStructures and OrganellesSection 3

NucleusThe nucleus is bounded by the nuclear envelope consisting a phospholipid bilayer, similar to the plasma membraneThe nucleus contains the DNA (deoxyribonucleic acid), the heredity information of the cellThe nucleus is the brain of the cellCells

Cells

NucleusAlso visible within the nucleus are one or more nucleoli, concentrations of DNA in the process of manufacturing the components of ribosomesCells

Cells

RibosomesRibosomes are manufactured in the nucleus and consist of ribosomal RNA and proteinRibosomes are the site of protein synthesisRibosomes translate genetic information (DNA) into specific polypeptide chains & proteinsCells

Cells

Endomembrane SystemComposed of the same phospholipid bilayer as the cell membraneThey are membrane-bound organelles in eukaryotic cellsSimilar to the organs of our bodiesEndomembrane systems only occur in eukaryotic cells

Endomembrane SystemComponents of the endomembrane system:Nuclear envelopeEndoplasmic reticulumMitochondria (has 2 lipid bilayers)Chloroplasts (has 2 lipid bilayers)Golgi apparatusLysosomesVacuolesVesicles

Endoplasmic ReticulumThe endoplasmic reticulum or ER, consists of stacks of flattened sacs of membraneThe best way to determine if the structure is the ER or Golgi apparatus is if it is connected to the nucleus. ER is connected

Cells

Cells

Endoplasmic ReticulumCells

Cells

Endoplasmic ReticulumRough ERSmooth ERWhen ribosomes are present, the ER is called the rough ER and providesAids in protein synthesis

Smooth ER, without ribosomes, is responsible for the synthesis of lipids and hormones.Cells

Cells

Golgi ApparatusThe Golgi apparatusThe Golgi modifies and package proteins and lipids into vesiclesThe Golgi also produces lysosomesThink of it as Fed ExCells

Cells

MitochondriaMitochondria carry out aerobic respiration, a process in which energy (in the form of ATP) is obtained from organic molecules (glucose)Its the powerhouse of the cellMitochondria are found in both plant and animal cellsSince it converts food to usable energy (ATP), what type of cell would have a lot of mitochondria??

Mitochondria

ChloroplastsChloroplasts are specialized organelles found in algae and plants that carry out photosynthesis, the process of capturing energy from sunlight and converting it into useable energy (carbohydrates)

ChloroplastsCells

Cells

ChloroplastsChloroplasts contain chlorophylls, which are responsible for the green color of a plant and are the key light-trapping molecules in photosynthesisChloroplast are not found in animal cells. Why not??

Chloroplasts and MitochondriaAdd this to your notes!!!!Both chloroplasts and mitochondria have their own circular DNA and ribosomes, just like bacteriaThey also reproduce the same way as bacteriaThis suggests that chloroplasts and mitochondria may have once been bacteria

Vacuoles & VesiclesVacuoles/ Vesicles are fluid-filled membrane bound bodiesThey may contain food particles or digestive enzymes (found in lysosomes)Transport substances throughout the cellRelease of cellular waste products

Vacuoles & Vesicles-Central vacuoles are large bodies that store water and occupies most of the interior of plant cells-If the central vacuole runs low on water, the plant will begin to wilt-The central vacuole in plants stores starch, pigments, and toxic substancesCells

Cells

LysosomesLysosomes are vesicles from the Golgi apparatus that contain hydrolytic digestive enzymesThey are the cells stomachLysosomes play an important role in:Intracellular digestion such as breaking down food, cellular debris, and foreign invaders such as bacteria

LysosomesCells

Cells

CytoskeletonThe cytoskeleton is the internal structure of the cytoplasm and is involved in establishing the shape of the cell and coordinating movementsCells

Cells

CytoskeletonCells

Cells

CiliaShort, numerous projections that look like hairsCellular Structure and FunctionFlagellaLonger and less numerous than ciliaCreate movement with a whiplike motionStructures and OrganellesSection 3

Cellular Structure and FunctionSection 3Table 7.1 Summary of Cell StructureTable 7.2 Summary of Cell StructureTable 7.3 Summary of Cell Structure

Cellular Structure and FunctionPlant and Animal Cell StructuresStructures and OrganellesSection 3

Structures only found in Plant Cellscells:Cell Wall

Chloroplasts

Central Vacuole

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