Cellular StructureCellular Structure

NucleusNucleus

The control The control center of the cell center of the cell (metabolism, (metabolism, protein protein synthesis)synthesis)

Nucleus: FYINucleus: FYI

Most cells contain only one nuclei;Most cells contain only one nuclei; Skeletal muscle = manySkeletal muscle = many Mature RBCs = noneMature RBCs = none

NucleolusNucleolus

Dense region that contains DNA/RNADense region that contains DNA/RNA Synthesizes RNA and ribosomesSynthesizes RNA and ribosomes

CytoplasmCytoplasm The watery The watery

fluid which fluid which contains the contains the materials which materials which enter the cell.enter the cell.

Dissolves things, Dissolves things, supports cell supports cell structure.structure.

CytoplasmCytoplasm

Three parts:Three parts: 1. Cytosol (liquid)1. Cytosol (liquid) 2. Organelles (little organs)2. Organelles (little organs) 3. Inclusions (insoluble particles)3. Inclusions (insoluble particles)

OrganellesOrganelles Intracellular Intracellular

structure that structure that performs a performs a specific function specific function or group of or group of functions. functions. (cellular (cellular respiration, respiration, releasing releasing energy)energy)

MitochondriaMitochondria

The The “powerhouse” “powerhouse” of the cell. of the cell.

They create They create food to obtain food to obtain energy for cell energy for cell activities. activities.

Produces 95% Produces 95% of ATP of ATP

MitochondriaMitochondria

# of # of mitochondria = mitochondria = energy level energy level neededneeded

MatrixMatrix

CristaeCristae

Lots of folds in mitochondriaLots of folds in mitochondria

The cristae greatly increase the The cristae greatly increase the inner membrane's surface area. inner membrane's surface area. It is on these cristae that food It is on these cristae that food (sugar) is combined with oxygen (sugar) is combined with oxygen to produce ATP - the primary to produce ATP - the primary energy source for the cell.energy source for the cell.

RibosomesRibosomes

Makes proteins Makes proteins in the cell. in the cell. “Protein “Protein factories”- aka. factories”- aka. protein protein synthesis synthesis

Contains RNA Contains RNA

RibosomesRibosomes

Free-Free-floating:floating:•Proteins are Proteins are made and made and enter in the enter in the cytosolcytosol

FixedFixed•Proteins Proteins

enter ER enter ER where they where they are modified are modified and and packaged for packaged for export.export.

Endoplasmic Reticulum (ER)Endoplasmic Reticulum (ER)

1.1. SynthesisSynthesis

2.2. StorageStorage

3.3. TransportTransport

SynthesisSynthesisER makes ER makes

•CarbohydratesCarbohydrates•LipidsLipids

StorageStorageStorage of molecules Storage of molecules that are absorbed from that are absorbed from the cytosol.the cytosol.

TransportTransportNetwork of membranes. Network of membranes. (Travel anywhere)(Travel anywhere)

Smooth (SER)Smooth (SER)

Lack Lack ribosomes ribosomes (smooth)(smooth)

Focus on Focus on making making carbohydrates carbohydrates and lipidsand lipids

Rough (RER)Rough (RER)

Contain Contain ribosomes ribosomes (hence (hence rough)rough)

Focus on Focus on making making proteinsproteins

Golgi ApparatusGolgi Apparatus

Package Package proteins for proteins for storage and storage and secretion from secretion from the cell.the cell.

Exocytosis, Exocytosis, package package particles (forms particles (forms lysosomes)lysosomes)

Golgi ApparatusGolgi Apparatus

Page 55 of text.Page 55 of text.Example of exocytosis Example of exocytosis and membrane and membrane reconstruction.reconstruction.

LysosomesLysosomes

Digest worn Digest worn out or out or unneeded cells unneeded cells and cell parts. and cell parts.

LysosomesLysosomes

Packages of digestive enzymes.Packages of digestive enzymes. Fight pathogensFight pathogens Why?????Why?????

Specialized StructuresSpecialized Structures

Organelles that are not common to Organelles that are not common to all cells, therefore they are not all cells, therefore they are not necessary for the cell to operate. necessary for the cell to operate.

                  

            

MicrotubulesMicrotubules

Hollow tubes that give support and Hollow tubes that give support and strength strength

CentrosomeCentrosome

The centrosome, also called the The centrosome, also called the "microtubule organizing center", is "microtubule organizing center", is an area in the cell where microtubles an area in the cell where microtubles are produced. are produced.

CiliaCilia

Hair-like microtubules attached to the Hair-like microtubules attached to the plasma membrane that often help in plasma membrane that often help in movement movement

FlagellaFlagella

A tail like structure used for A tail like structure used for movementmovement

MicrovilliMicrovilli

Extension/folding of membrane to Extension/folding of membrane to help increase surface area. help increase surface area.

Found in kidney and intestinal cells. Found in kidney and intestinal cells.

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AKA: cell membraneAKA: cell membrane

COLOR CODE (Page 52 new)COLOR CODE (Page 52 new)

Glycoproteins: (Globular) GGlycoproteins: (Globular) G Channel: HChannel: H Phospholipids Heads: APhospholipids Heads: A Fatty acid tails: SFatty acid tails: S Carbohydrate (sugar) Carbohydrate (sugar)

1. Hydrophobic1. Hydrophobic““Dislike Water”Dislike Water”Two fatty acid tailsTwo fatty acid tails

2. Hydrophilic2. Hydrophilic““Likes Water”Likes Water”Non-lipid headNon-lipid head

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The lipid tails will not associate with The lipid tails will not associate with water molecules, and this allows the water molecules, and this allows the cell membrane to act as a physical cell membrane to act as a physical barrier. The phospholipid bilayer also barrier. The phospholipid bilayer also contains cholesterol, which makes the contains cholesterol, which makes the bilayer stronger, more flexible and bilayer stronger, more flexible and permeable. permeable.

3. Glycoprotein (Channel & Carrier)3. Glycoprotein (Channel & Carrier)

Globular proteinsGlobular proteins: have a : have a structural role as well as a role in structural role as well as a role in transporting ions in and out the cell-transporting ions in and out the cell-they are rounded and compact. they are rounded and compact.

4. Receptor Proteins4. Receptor Proteins

Receptor Proteins:Receptor Proteins: are found on are found on the bilayer, deal with the bilayer, deal with communication, recognition and communication, recognition and transport.transport.

Ex: Binding of insulin: Tell cell to Ex: Binding of insulin: Tell cell to increase intake of glucose.increase intake of glucose.

5. Carbohydrates & Lipids 5. Carbohydrates & Lipids

Are found on the outer surface of the Are found on the outer surface of the cell and have 3 major roles:cell and have 3 major roles:

1. important cell lubricants and 1. important cell lubricants and adhesivesadhesives

2. act as receptors for exracellular 2. act as receptors for exracellular compoundscompounds

3. part of a recognition system that 3. part of a recognition system that keeps keeps the immune system from the immune system from attacking its own tissues. attacking its own tissues.

Plasma Membrane (review)Plasma Membrane (review)

Controls what enters and leaves the Controls what enters and leaves the cell. It contains the cell contents and cell. It contains the cell contents and protects the cell. protects the cell.

composed of lipids composed of lipids hydrophobic lipid ends facing inward hydrophobic lipid ends facing inward

and the hydrophilic phosphate ends and the hydrophilic phosphate ends facing outward. Also called facing outward. Also called lipid lipid bilayer.bilayer.

Functions of cell membraneFunctions of cell membrane

The cell membrane The cell membrane or plasma or plasma membrane has four membrane has four basic functions.basic functions.

Functions of cell membraneFunctions of cell membrane

1. Boundary between cell 1. Boundary between cell fluidsfluids

Cytoplasm vs. Cytoplasm vs. extracellular fluid.extracellular fluid.

2. Regulation of 2. Regulation of exchangeexchange• Selects what goes in Selects what goes in

and what goes out and what goes out (ions, waste, etc…)(ions, waste, etc…)

3. Communication: 3. Communication: •Senses environment Senses environment and adjusts. and adjusts.

4. Structural Support:4. Structural Support:•Gives cell support and Gives cell support and shape. shape.