CELLSCELLS

Organization of Living Organization of Living OrganismsOrganisms

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Copy these questions & answer them Copy these questions & answer them while we watch the brain pop.while we watch the brain pop. 1. Name the organelles that they 1. Name the organelles that they

mentioned in the video and a brief functionmentioned in the video and a brief function 2. The kidneys and intestines are compared 2. The kidneys and intestines are compared

to what 2 organelles in the cell?to what 2 organelles in the cell? 3. Why do we have different types of cells?3. Why do we have different types of cells?

Cell TheoryCell Theory

1.1. All living things are made up of cellsAll living things are made up of cells

2.2. Cells are the basic unit of structure Cells are the basic unit of structure and function for all living thingsand function for all living things

3.3. All cells arise from pre-existing cellsAll cells arise from pre-existing cells

Cells specialize and Cells specialize and are grouped into are grouped into tissuestissues

Different tissues Different tissues combine to form combine to form organsorgans

Several organs Several organs form systems to form systems to carry out life carry out life functions functions

Cells = The basic structure of Cells = The basic structure of life!life!

Cells have specific structures that perform Cells have specific structures that perform specific jobs called ORGANELLES specific jobs called ORGANELLES

Organelles are floating in the jellylike Organelles are floating in the jellylike substances in the cell called CYTOPLASMsubstances in the cell called CYTOPLASM

Cellular OrganizationCellular Organization• Every human cell has:

• Plasma Membrane (cell membrane)• Surrounds cell and keeps it intact• Regulates what goes in and out of the cell• Phospholipid bilayer that is semipermeable (allows

only certain molecules in)• Nucleus

• Large, centrally located• Contains chromosomes• Control center of the cell• Controls metabolic functioning & structural

characteristic of cell• Cytoplasm

• Found between the nucleus and plasma membrane• Contains water and various types of molecules• Contains organelles

Cellular OrganizationCellular Organization• Organelles

• Small, membranous structures• Each has a specific function• Keeps various cellular activities separate from each

other

• Cytoskeleton• Network of interconnected filaments and

microtubules in cytoplasm• Maintains cell shape and all the cell and contents to

move

Plasma MembranePlasma MembraneThin structure that surround the cell – composed of Thin structure that surround the cell – composed of

lipids and proteinslipids and proteinsImportant functions:Important functions:1.1. Separates contents of cell from outside Separates contents of cell from outside

environmentenvironment2.2. Controls which molecules enter and leave the Controls which molecules enter and leave the

cell (selective barrier)cell (selective barrier)3.3. Recognize and respond to chemical signals with Recognize and respond to chemical signals with

“receptor” molecules “receptor” molecules allow interactions allow interactions between cellsbetween cells

Phospholipid BilayerPhospholipid Bilayer Has attached/embedded proteinsHas attached/embedded proteins Polar head and nonpolar tailsPolar head and nonpolar tails

Polar heads are charged, hydrophilic, face outwardPolar heads are charged, hydrophilic, face outward Nonpolar tails are hydrophobic, face inwardNonpolar tails are hydrophobic, face inward

At body temperature the bilayer is a liquid, At body temperature the bilayer is a liquid, consistency of olive oil.consistency of olive oil.

Fluid-mosaic modelFluid-mosaic model –description of membrane –description of membrane structurestructure Protein molecules have changing patternProtein molecules have changing pattern

Short chains of sugar are attached to outer Short chains of sugar are attached to outer surfaces of some proteins & lipidssurfaces of some proteins & lipids Glycoproteins, glycolipidsGlycoproteins, glycolipids

Glycoproteins are specific to each cell and belong to specific Glycoproteins are specific to each cell and belong to specific individualsindividuals

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Take out homework from Tuesday Take out homework from Tuesday NightNight

What are the 3 main parts of the What are the 3 main parts of the human cell?human cell?

What is the fluid-mosaic model?What is the fluid-mosaic model?

NucleusNucleus

Stores genetic informationStores genetic information Every cell has genetic information, but each cell type Every cell has genetic information, but each cell type

has certain genes turned on and offhas certain genes turned on and off Control center of the cellControl center of the cell

Metabolism is controlled hereMetabolism is controlled here Contains a nucleolusContains a nucleolus

Ribosomal RNA is produced hereRibosomal RNA is produced here Surrounded by a nuclear envelopeSurrounded by a nuclear envelope

Has nuclear pores to allow certain proteins to pass Has nuclear pores to allow certain proteins to pass throughthrough

RibosomesRibosomes

Composed of two subunits, 1 large, 1 smallComposed of two subunits, 1 large, 1 small Found free within the cytoplasm or Found free within the cytoplasm or

attached to the endoplasmic reticulumattached to the endoplasmic reticulum Makes proteinsMakes proteins

Endoplasmic ReticulumEndoplasmic ReticulumSystem of channels through the cell System of channels through the cell

– – communication and transportcommunication and transport- Smooth ER: no ribosomesSmooth ER: no ribosomes

- Synthesizes phospholipidsSynthesizes phospholipids- In testes – produces testosteroneIn testes – produces testosterone- In liver – detoxifies drugsIn liver – detoxifies drugs

- Rough ER: has ribosomesRough ER: has ribosomes- Proteins are made here then processed and modifiedProteins are made here then processed and modified

LysosomeLysosomeContain digestive enzymes “suicide sacs” Contain digestive enzymes “suicide sacs”

Join with vacuoles to break down food Join with vacuoles to break down food

– – If the lysosome ruptures or breaks If the lysosome ruptures or breaks

the cell will diethe cell will die

Golgi BodyGolgi Body Consists of a stack of 3 to 20 slightly curved Consists of a stack of 3 to 20 slightly curved

sacculessaccules One side is directed toward the ER, other side is directed One side is directed toward the ER, other side is directed

toward plasma membranetoward plasma membrane Packages secretions and transports materials, Packages secretions and transports materials,

which are then carried in vesicles through the which are then carried in vesicles through the cytoplasm to other parts of the cell, or are excreted cytoplasm to other parts of the cell, or are excreted from the cellfrom the cell

Vacuoles & PeroxisomesVacuoles & Peroxisomes VacuolesVacuoles

Isolate substances captured inside the cellIsolate substances captured inside the cell May contain parasites that are awaiting digestion by lysosomesMay contain parasites that are awaiting digestion by lysosomes

PeroxisomesPeroxisomes Similar in structure to lysosomesSimilar in structure to lysosomes Vesicles that contain enzymesVesicles that contain enzymes Detoxify drugs, alcohol and other potential toxinsDetoxify drugs, alcohol and other potential toxins Found in great numbers in the liver and kidneysFound in great numbers in the liver and kidneys Break down fatty acids so that the fats can be metabolizedBreak down fatty acids so that the fats can be metabolized

MitochondriaMitochondria

Bounded by a double membraneBounded by a double membrane Inner membrane folded to form shelves Inner membrane folded to form shelves

(cristae)(cristae) Matrix (inner space) filled with gel-like Matrix (inner space) filled with gel-like

fluidfluid Site of ATP productionSite of ATP production Powerhouse of the cellPowerhouse of the cell

CentriolesCentrioles

Short cylinders with 9 outer Short cylinders with 9 outer microtubule triplets and no center microtubule triplets and no center microtubulesmicrotubules

Pair of centrioles is each cellPair of centrioles is each cell Duplicate and separate during cell Duplicate and separate during cell

divisiondivision

Cilia and FlagellumCilia and Flagellum Projections from the cell. They are made Projections from the cell. They are made

up of microtubules. They are motile and up of microtubules. They are motile and designed either to move the cell itself or designed either to move the cell itself or to move substances over or around the to move substances over or around the cell cell

Lesson 2Lesson 2

Crossing the Plasma Crossing the Plasma MembraneMembrane

Simple DiffusionSimple Diffusion

Random movement of simple atoms Random movement of simple atoms or molecules from an area of high or molecules from an area of high concentration to an area of low concentration to an area of low concentration until equal distributionconcentration until equal distribution

NO ENERGY IS INVOLVED!!!NO ENERGY IS INVOLVED!!!

OsmosisOsmosis

Diffusion of Diffusion of waterwater across the plasma across the plasma membranemembrane Occurs when there is an unequal Occurs when there is an unequal

concentration of waterconcentration of water Osmotic pressure Osmotic pressure – force exerted on – force exerted on

semipermeable membrane because semipermeable membrane because water has moved from high water has moved from high concentration to lower concentrationconcentration to lower concentration

OsmosisOsmosis

Solutes Solutes – dissolved substances– dissolved substances SolutionSolution – water is more concentrated (least amount – water is more concentrated (least amount

of dissolved substances, closest to pure water)of dissolved substances, closest to pure water) TonicityTonicity – degree to which a solutions concentration – degree to which a solutions concentration

of solute vs. water causes water to move in or out of of solute vs. water causes water to move in or out of cellscells

IsotonicIsotonic – – an equal concentration of solutes and an equal concentration of solutes and solvent on both sides of membranesolvent on both sides of membrane

HypotonicHypotonic – solutions that cause cells to swell – solutions that cause cells to swell HypertonicHypertonic – solutions that cause cells to shrink – solutions that cause cells to shrink

FiltrationFiltration

Movement of liquid from high pressure to Movement of liquid from high pressure to low pressurelow pressure Occurs in capillaries, pushes water and Occurs in capillaries, pushes water and

dissolved solutes out of the capillary through dissolved solutes out of the capillary through tiny porestiny pores

Transport by CarriersTransport by Carriers

Facilitated diffusion –Facilitated diffusion – a molecule is a molecule is transported across the plasma membrane transported across the plasma membrane from high concentration to low from high concentration to low concentration by means of a helper concentration by means of a helper protein. NO ENERGY REQUIREDprotein. NO ENERGY REQUIRED

Active transportActive transport – – molecule is moving molecule is moving from low concentration to high from low concentration to high concentration. ENERGY REQUIRED!!!concentration. ENERGY REQUIRED!!!

Endocystosis vs. ExocytosisEndocystosis vs. Exocytosis

EndocytosisEndocytosis Portion of plasma Portion of plasma

membrane forms an membrane forms an inner pocket to engulf inner pocket to engulf a substancea substance

Membrane pinches off Membrane pinches off to form a vesicleto form a vesicle

Two formsTwo forms Phagocytosis – cell Phagocytosis – cell

eatingeating Pinocytosis – cell Pinocytosis – cell

drinkingdrinking

ExocytosisExocytosis Vesicle fuses with Vesicle fuses with

plasma membrane as plasma membrane as secretion occurssecretion occurs

Content CheckContent Check

Which process requires cellular ATP Which process requires cellular ATP energy?energy? A. osmosisA. osmosis B. facilitated diffusionB. facilitated diffusion C. active transportC. active transport D. simple diffusionD. simple diffusion

Video

HomeworkHomework

Study Questions #7-12Study Questions #7-12

Lesson 3Lesson 3

The Cell CycleThe Cell Cycle

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Take out Homework From last nightTake out Homework From last night Take out Cell Division video Take out Cell Division video

worksheetworksheet

Cell DivisionCell Division

Cell CycleCell Cycle Orderly set of stages that take place between the Orderly set of stages that take place between the

time a cell divides and the time the daughter cells time a cell divides and the time the daughter cells dividedivide

ApoptosisApoptosis – programmed cell death – programmed cell death Stages:Stages:

Interphase – not dividing, carries on regular activites, Interphase – not dividing, carries on regular activites, gets ready to dividegets ready to divide

G1 Phase – return to normal pre-mitotic conditionG1 Phase – return to normal pre-mitotic condition S phase – DNA replication occursS phase – DNA replication occurs G2 phase – cell synthesizes proteins that will aid in cell G2 phase – cell synthesizes proteins that will aid in cell

divisiondivision

DNA ReplicationDNA Replication

An exact copy of DNA is producedAn exact copy of DNA is produced Each strand of the helix is used as a templateEach strand of the helix is used as a template

Before replication - two strands are hydrogen bonded to Before replication - two strands are hydrogen bonded to one anotherone another

During replication – old strands “unzip” and unwindDuring replication – old strands “unzip” and unwind New strands are made, enzyme DNA polymerase joins the New strands are made, enzyme DNA polymerase joins the

new nucleotides together forming new helices.new nucleotides together forming new helices. End result – two resulting double helices are identical.End result – two resulting double helices are identical.

Each strand of double helix is equal to 1 chromatid, at Each strand of double helix is equal to 1 chromatid, at the end of replication each chromosome is composed of the end of replication each chromosome is composed of 2 sister chromatids2 sister chromatids

Stages of MitosisStages of Mitosis

ProphaseProphase MetaphaseMetaphase AnaphaseAnaphase TelophaseTelophase

ProphaseProphase

Two pairs of centiroles are moving to Two pairs of centiroles are moving to opposite ends of the nucleusopposite ends of the nucleus

Spindle fibers appearSpindle fibers appear Nuclear envelope starts to disappearNuclear envelope starts to disappear Chromosomes are visibleChromosomes are visible Spindle fibers attach to centromeresSpindle fibers attach to centromeres

MetaphaseMetaphase

Nuclear envelope is completely goneNuclear envelope is completely gone Paired chromosomes are at the Paired chromosomes are at the

equatorequator Fully formed spindlesFully formed spindles

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Take out Homework From Last nightTake out Homework From Last night

List the 5 stages of mitosis.List the 5 stages of mitosis.

AnaphaseAnaphase

Sister chromatids separateSister chromatids separate Each cell receives a copy of each Each cell receives a copy of each

type of chromosometype of chromosome Chromosomes begin to move to Chromosomes begin to move to

opposite ends of the cellopposite ends of the cell

Teleophase and CytokinesisTeleophase and Cytokinesis

Chromosomes arrive at the polesChromosomes arrive at the poles Chromosomes become indistinct Chromosomes become indistinct

againagain Cytoplasm begins to divideCytoplasm begins to divide Cleavage furrow begins to occur – Cleavage furrow begins to occur –

pinches the cell in halfpinches the cell in half

Mitosis

HomeworkHomework

Study Questions pg 62 #13, 14, 16 & Study Questions pg 62 #13, 14, 16 & 1717

Protein SynthesisProtein Synthesis

DNA is template for RNA formation DNA is template for RNA formation and protein constructionand protein construction

Two Steps:Two Steps: Transcription – mRNA (messenger RNA) Transcription – mRNA (messenger RNA)

is producedis produced Translation – mRNA specifies the order Translation – mRNA specifies the order

of amino acids in a polypeptideof amino acids in a polypeptide

TranscriptionTranscription

DNA unzips and unwinds, binding with their RNA DNA unzips and unwinds, binding with their RNA counterpartscounterparts

Joined by RNA polymerase -> RNA molecule resultsJoined by RNA polymerase -> RNA molecule results Three forms of RNAThree forms of RNA

MessengerMessenger TransferTransfer RibosomalRibosomal

Codon – a sequence of three bases that Codon – a sequence of three bases that is complimentary to the DNA triplet(ex. is complimentary to the DNA triplet(ex. AAG)AAG)

TranslationTranslation

Uses several enzymes and all 3 types of RNAUses several enzymes and all 3 types of RNA Transfer RNA (tRNA) deliver amino acids to Transfer RNA (tRNA) deliver amino acids to

ribosomes which are composed of rRNA ribosomes which are composed of rRNA (ribosomal RNA) and protein(ribosomal RNA) and protein

At least 1 tRNA molecule for each of the 20 amino At least 1 tRNA molecule for each of the 20 amino acidsacids

Anticodon – a group of 3 bases that is Anticodon – a group of 3 bases that is complimentary to an mRNA codoncomplimentary to an mRNA codon

Animation

In class In class assignment/Homeworkassignment/Homework

Read Focus on Forensics “DNA Read Focus on Forensics “DNA Fingerprinting”Fingerprinting” Why is DNA so important to us?Why is DNA so important to us? How is DNA extracted from a sample?How is DNA extracted from a sample?

Study Question 15, on page 18-19Study Question 15, on page 18-19