Cell Organelles and Cell Organelles and featuresfeatures

Chapter 4Chapter 4

Plasma MembranePlasma Membrane

Also called cell membraneAlso called cell membrane

Allows certain molecules to enter and exit Allows certain molecules to enter and exit a cella cell

It separates internal metabolic reactions It separates internal metabolic reactions from the external environmentfrom the external environment

Phospholipid bilayerPhospholipid bilayer

Polar hydrophilic Polar hydrophilic (water loving) head(water loving) head

2 Polar hydrophobic 2 Polar hydrophobic (water fearing) fatty (water fearing) fatty acid tailsacid tails

Membrane Proteins Membrane Proteins

Often contain specific proteins embedded Often contain specific proteins embedded within the lipid bilayer.within the lipid bilayer.

NucleusNucleus

Controls most of the functions of the Controls most of the functions of the eukaryotic cell.eukaryotic cell.

Filled with jellylike fluid called nucleoplasm Filled with jellylike fluid called nucleoplasm that holds similar function of the sell that holds similar function of the sell cytoplasm.cytoplasm.

Houses cell’s genetic informationHouses cell’s genetic information

Nucleus cont.Nucleus cont.

DNA is in the DNA is in the threadlike structure threadlike structure called chromatin.called chromatin.

Nuclear EnvelopeNuclear Envelope

Surrounds nucleus with a double Surrounds nucleus with a double membrane.membrane.

Made up of 2 phospholipid bilayers.Made up of 2 phospholipid bilayers.

Nuclear pores cover the surface which Nuclear pores cover the surface which provide passageway for RNA and other provide passageway for RNA and other materials to enter and leave the nucleus.materials to enter and leave the nucleus.

NucleolusNucleolus

Denser area in nucleus that is mostly Denser area in nucleus that is mostly DNA. DNA.

Responsible for making Ribosomal RNA.Responsible for making Ribosomal RNA.

MitochondriaMitochondria

Tiny organelles that Tiny organelles that transfer energy from transfer energy from organic molecules to organic molecules to ATP.ATP.

ATP ultimately ATP ultimately powers most of the powers most of the cells chemical cells chemical reaction.reaction.

Mitochondrial DNAMitochondrial DNA

Mitochondria has its own DNA that can Mitochondria has its own DNA that can only be reproduced by the division of only be reproduced by the division of preexsiting mitochondria. preexsiting mitochondria.

RibosomesRibosomes

Very small, roughly spherical organelles Very small, roughly spherical organelles that are responsible for building protein.that are responsible for building protein.

Endoplasmic ReticulumEndoplasmic Reticulum

System of System of membranous tubes membranous tubes and sacs. and sacs.

Used as an Used as an intercellular highway. intercellular highway.

Rough ER and Rough ER and Smooth ERSmooth ER

Golgi Apparatus Golgi Apparatus

Receives vesicles Receives vesicles from the ER from the ER containing newly containing newly made proteins.made proteins.

VesiclesVesicles

Small spherical sacs that play different Small spherical sacs that play different parts.parts.

Lysosomes- bud from golgi apparatus and Lysosomes- bud from golgi apparatus and contain digestive enzymes.contain digestive enzymes.

Peroxisomes- Neutralize free radicals in Peroxisomes- Neutralize free radicals in the liver and kidney cells. the liver and kidney cells.

Protein SynthesisProtein Synthesis

Major functions of a cell.Major functions of a cell.1- proteins are assembled by ribosomes on the 1- proteins are assembled by ribosomes on the rough ER.rough ER.2- Vesicles transport proteins to the golgi 2- Vesicles transport proteins to the golgi apparatus.apparatus.3- Golgi breaks down proteins and packages 3- Golgi breaks down proteins and packages them in new vesicles.them in new vesicles.Vesicles release proteins that have destinations Vesicles release proteins that have destinations outside of the cell. outside of the cell. The remaining stay inside as lysosomes and The remaining stay inside as lysosomes and peroxisomes. peroxisomes.

CytoskeletonCytoskeleton

Uses thin tubes and filaments to give Uses thin tubes and filaments to give shape to a cell.shape to a cell.

MicrotubulesMicrotubules

Hollow tubes made from protein that hold Hollow tubes made from protein that hold organelles in place.organelles in place.

Cilia and Flagella Cilia and Flagella

Hair-like structures Hair-like structures that assist in that assist in movement.movement.