7.2 Eukaryotic Cell Structures and Their Functions

Eukaryotic cells have a what kind of surface to-to- volume ratio

large

large surface-to-volume ratio makes it Difficult for

molecules to diffuse across the entire cell

what do Organelles do in Eukaryotic cells

break up the large cell volume into smaller membrane-bound organelles

compartmentalization offers two advantages (Eukaryotic cell)

Separation of incompatible and increased efficiency of chemical reactions

The Nucleus has a ? envelope

Double-membrane

the nuclues has ? openings

pore

where are Ribosomal RNA synthesized

Nucleolus

the Nucleolus is where ? subunits are assembled

Ribosome

where is the Center for Information Storage and Processing

nucleus

where are chromosomes contained

nucleus

what occupies a distinct area in the nucleus

chromosome

where is DNA densely packed

periphery of the nucleus

where is DNA loosely packed

where is DNA densely packed of the nucleis

how long would the DNA molecules in a single human cell were unwound from their histones and placed end-to-end,

6 feet

Complex Molecular Machines that Manufacture Proteins

ribosomes

what do ribosomes lack

membrane

what is not considered an organelle

ribosomes

where are ribosomes free

in the cytosol

what do ribosomes do that remain in the cytosol

Manufacture proteins

what are some ribosomes attached to

endoplasmic reticulum

what is do ribosomes Manufacture

proteins

endoplasmic reticulum

organelle that is an extension of the nuclear envelope

what are the two types of Endoplasmic Reticulum

rough and smooth

what does the Rough Endoplasmic Reticulum house

ribosomes

what does the Smooth Endoplasmic Reticulum do

Synthesizes Lipids

Proteins move to the

lumen of the rough ER

Lumen

inside of any sac-like structure

proteins in the lumen are

folded and processed

Proteins made on the RER may

Carry messages to other cells, Carry messages to other cells, and Catalyze reactions

what does the smooth ER lack

ribosomes

the smooth ER contains

enzymes

what does the enzymes in the smooth ER do

catalyze reactions involving lipids

what is needed by the organism from the smooth ER

Synthesize lipids

what does in the smooth ER do

Break down lipids and other molecules that are poisonous

the smooth ER is a reservoir for

Ca2+

Golgi Apparatus

Two Sided (Cis & Trans)

cisternae

series of stacked, flat, membranous sacs

where is cisternae located

Golgi Apparatus

The cis (“on this side”) Golgi Apparatus

surface is closest to the nucleus

The trans (“across”) Golgi Apparatus

surface is oriented toward the plasma membrane

what is at the back of the arrow and what is at the front side called

cis; trans

what Receives Products from RER & Ships Them Out

Golgi Apparatus

the Golgi Apparatus does what from the stuff from the rough ER

Processes, sorts, and ships proteins

what does the cis side of a Golgi apparatus do

receives products from the rough ER

what does the trans side of the Golgi apparatus do

ships them out to other organelles or the cell surface

what do Membranous vesicles do

carry materials to and from the organelle

Lysosomes

Recycling Centers Found Only in Animal Cells

how many different enzymes do Lysosomes contain

40

what do the Enzymes in Lysosomes do

hydrolyze macromolecules and export monomers

what pH does lysosomes work best at

5

pH of Proton pumps in membrane

maintain low internal pH

what acid is Lysosomes

Acid hydrolases

what is part of the Endomembrane System

Lysosomes

Endomembrane System consist of

ER + Golgi + Lysosomes

lysosomes function in the Endomembrane System

Produces, processes, and transports proteins and lipids

what is first in the Endomembrane System for Lysosomes

Synthesized in the ER

what is second in the Endomembrane System for Lysosomes

Processed in the Golgi apparatus

what is third in the Endomembrane System for Lysosomes

Shipped to lysosomes

Vacuoles

Large, Membrane-bound Structures in Plants & Fungi

what are functions of vacuoles

digestion, store water, and ions to help the cell maintain its normal volume

In seeds what is the vacuole filled with

proteins

in flower petals or fruits what do vacuoles contain

pigments

for protection vacuoles might contain

pigments

everything a vacuole contains

noxious compounds, proteins, and pigments

Distinct to Cell Type

Peroxisomes

where do Peroxisomes Originate from

ER

what reactions do Peroxisomes do

Redox reactions

Redox reactions

e- transfers

what cells contain enzymes that oxidize ethanol (Peroxisomes)

Liver cells

Oxidation often produces in Peroxisomes

hydrogen peroxide

what does the enzyme catalase in peroxisomes

detoxifies

Mitochondria

Supplies ATP to Cells

how many membranes does the Mitochondria contain

2

Inner Mitochondria membranes

folded into a series of sac-like cristae

Solution inside =

the mitochondrial matrix

what does Mitochondria have their own of

mitochondrial DNA (mtDNA)

what does the Mitochondria their own of

ribosomes

Chloroplast

Where photosynthesis takes place

Most Plant & Algae Cells have

Chloroplasts

Chloroplasts have their own

DNA

Chloroplasts can manufacture

ribosomes

how many membranes do Chloroplast have

3

Innermost membrane of Chloroplast contains

flattened sacs called thylakoids

Thylakoids

arranged in stacks called grana

what does the innermost membrane of Chloroplast surround

thylakoids is the stroma

Endosymbiotic Theory or Symbiogenesis

Bacteria were engulfed and a mutually beneficial relationship evolved

what could have been free living bacteria

Chloroplasts and mitochondria

Evidence for endosymbiosis

Mitochondria and chloroplasts contain their own DNA, Grow and divide independently of cell division, Synthesize their own small ribosomes

Cytoskeleton

Comprises Protein Fibers

what Gives cells shape and structural stability

Cytoskeleton

Cytoskeleton aids in

cell movement

what does the Cytoskeleton Organize

organelles and other cellular structures into a cohesive whole

Cytoskeleton Transports …

materials within the cell

The Eukaryotic Cell Wall

Structural Support

what has a stiff outer cell wall

Fungi, algae, and plants