Chapter 4-Powerpoint Lectures Flashcards
When and who discovered cells?
in 1665 by Robert Hooke
Cell Theory
1) All organisms are composed of one or more cells
2) Cells are the smallest living units of all living organisms
3) Cells arise only by division of a previously existing cell
How do some cells increase surface area?
extensions or folds
What are the two types of electron microscopes?
Transmission and scanning types
Why is it hard for water soluble ions to go through the plasma membrane?
b/c membrane is made of a hydrophobic bilayer
what does the cytoplasm contain?
cytosol and cytoskeleton
What does the cytosol contain?
ions, various organic molecules, and organelles
What help maintain a cell’s shape and plays a role in chromosome segregation?
cytoskeleton
What domains are Prokaryotes?
Bacteria and Arcaea
What domain are Eukaryotes?
Eukarya
Where is the genetic information stored in a prokaryote?
nucleoid, single and circular molecule called plasmids
Where is the genetic information stored in a eukaryotes?
nucleus
sugars that coat a cell wall of a prokaryotes
glycocalyx
loosely attached glycocalyx
slime layer
firmly attached glycocalyx
capsule
Where is ATP synthesized in prokaryotes?
plasma membrane
What is the role of pili?
attach the cell to surfaces of other cells
What are the three shapes of prokaryotes?
spherical, rodlike, and spiral
What carries DNA to the ribosomes in the cytoplasm?
mRNA
Differences in organelles between plant and animal cells?
Plant cells contain chloroplasts, vacuoles, and a cell wall outside the cell membrane
In cell fractionation, what order do things participate out in?
whole cells, cell fragments, nuclei, mitochondria and chloroplasts, ribosomes and proteins and nucleic acids
How many nucleus do most eukaryotic cells possess?
1
Where does ribosomal RNA synthesis take place?
Nucleous
Where are ribosomal subunits formed
Nucleous
where do molecules enter and exit out of the nucleus?
nuclear pores
How many phospholipid bilayers are in the nuclear envelope?
2
What is the protein structural layer in the nucleus?
nuclear lamina
What shape is DNA in eukaryotes?
linear
What is the liquid in the nucleus?
nucleoplasm
What is chromatin?
Combo of DNA and protiens
What helps proteins get where they need to go?
nuclear localization signal
What subunits are eukaryotic ribosomes made of?
small and large
What are eukaryotic ribosomes made of?
rRNA and protiens
Where are eukaryotic ribosomes located?
cytosol and some are attached to membranes
What are small membrane-bound sacs that transfer substances between parts of the system?
vesicles
What is the purpose of the endomembrane system?
dividing the cell into compartments
What is included in the endomembrane system?
nuclear envelope, endoplasmic reticulum, Golgi complex, lysosomes, vesicles, and plasma membrane
what is the cisterna formed by?
a single membrane that surrounds an enclosed space (ER lumen)
What are the two types of ER?
Smooth ER and Rough ER
Which ER has ribosomes on the outer sufarce?
Rough ER
where do proteins fold into their final form?
rough ER
What happens in the rough ER
proteins fold into their final form, chemical modification, delivered to other region in vesicles that pinch off
What happens in the smooth ER?
lipid synthesis (phospholipid membranes) and hormone synthesis
What does the smooth ER in the liver do?
detoxify harmful substances
What are the golgi networks?
cis-, medial-, trans-
Where do proteins enter on the Golgi apparatus?
cis face
Where do the proteins bud off from on the Golgi apparatus?
trans face
What is the function of the Golgi apparatus?
distribution of molecules, formation of glycoproteins and glycolipids, final protein folding, stores secreted material
What are proteins that are to be secreted transported in?
secretory vesicles
How do cells get rid of material?
exocytosis—secretory vesicles fuse with plasma membrane and release its contents
How many bilayers do lysosomes have?
1
Are lysosomes found in plants and animals?
no, just animals
Where are lysosomes made?
trans-Golgi network
What do lysosomes do?
digest/remove substances via acidic environment
What is the process of destroying foreign matter or cells?
phagocytosis
What is destroying organelles?
autophagy
How do cells bring materials into it?
endocytosis
What is pinocytosis?
Where foreign soluble material is digested in the lysosome
What is the pathway to excrete material?
Rough ER (lumen), transport vesicles, Golgi, secretary vesicles, plasma membrane
What is invagination?
when the budding of vesicles becomes larger
Why do we need to coat and uncoat the vesicles?
The coating determines the direction of movement of the vesicle. It can only fuse with membrane when it uncoats
What is produced by peroxisomes?
Hydrogen peroxide
What makes hydrogen peroxide harmless?
catalase—only exists in peroxisomes
What is the structure of lysosomes
single bilayer membrane vesicles
Which 2 organelles have their own DNA
mitochondria and chloroplasts
How many membranes do mitochondria have?
2 phospholipid bilyaers
How do mitochondria increase the surface area?
colds called cristae
What is the innermost compartment of mitochondria?
matrix
What is contained in the mitochondrial matrix?
DNA, ribosomes, and other components
Where does cellular respiration occur?
In matrix and cristae of mitochondria
What type of membranes do chloroplasts have?
double
What is endosymbiotic theory?
An ancient eukaryotic cell engulfed and ancient aerobic prokaryotic cell= mitochondria. in an animal cell.
Symbiotic relationship
Did animal or plant cells come first?
animal as seen in endosymbiotic theroy
what does the cytoskeleton do?
maintain shape, internal organization, movement
What two types of tubulin are there? —microtubules
alpha and beta—-added in a pattern (A,B,A,B,…)
How do tubulin filaments grow and decrease in length?
removal or addition of dimers called polymerization and depolymerization
Where are intermediate filaments job?
support internal structure of cell
How big are the largest microtubules?
25nm in diameter
Where do microtubules radiate from?
centersome—-aster like star
What are the centriole formed from?
micortubules
Orientation of centriole?
perpendicular
Shape of centriole?
barell shape
What does dyneins do?
motor protein carries cargo from outer edge of cell to center
What does kinesins do?
motor protein carries cargo from center of cell to out edge
How do vesicles move?
the motor proteins have two “feet” and walk along microtubules
Structure of intermediate filaments
parallel bundles
How thick are microfilaments?
7nm in diameter
What type of polarity do microfilaments have?
plus and minus end
What is cytoplasmic streaming
transports stuff and is responsible for ameobiod movement
Where do flagella and cilia arise from?
centrioles
How are flagella and cila different?
cilia are shorter
Structure of flagella and cilia?
9+2 complex
How do flagella move?
s-shaped wave
How do cilia move?
power and recovery stroke. like rowing a boat
What is the waving and bending mechanism?
in cilia and flagella dynein motor proteins slide the microtubule doublets over each other
How is DNA organized in a eukaryotic cell?
chromosomes
Which end do you add dimers to microtubles?
plus end
Which end do you remove dimers from imcrotubules?
minus end
What bonds are responsible in tertiary structure?
hydrogen bonds, disulfide linkages, ionic bonds, hydrophobic interactions, an der Waals interactions
What does tertiary structure determine?
function and solubility
What did the Anfinsen Experiment determine?
primary structure determines secondary and tertiary structure—-which is why the protein was able to renature
Do pili exist on eukaryotes and prokayotes?
No, just prokaryotes
Do flagella exist on eukaryotes and prokaryotes?
yes, they exist on both
Do cilia exist on eukaryotes and prokaryotes?
No, just eukaryotes
What are microfilaments composed of?
actin subunits
Do chloroplasts also occur in algal protists
yes
What are the three things under plastids?
chloroplasts, amylopasts, chromoplasts
Which are yellow-green plastids?
chloroplasts
What are colorless plastids that store starch?
amyloplasts
Which are colored plastids that are responsible for ripening>
chromoplasts
Do all plastids contain DNA?
yes
What types of membranes are in a chloroplasts?
inner and outer boundary membranes
What is the equivalents of stroma in chloroplasts?
matirx
What is chlorophyll stored?
thylakoid membranes in chloroplasts
How much space does the central vacuole occupy?
90% or more
Function of central vaucole?
storage, breakdown enzymes, contain molecules that provide chemical defense
Membrane that srrounds central vacuole?
tonoplast
What is the cell wall made of?
cellulose
What is cellulose made of? linkage?
beta glucose, beta (1,4) linkage
Structure of cell wall?
primary cell wall, secondary cell wall, and middle lamella
How is the primary cell wall different that the secondary cell wall?
secondary cell wall has more layers of cellulose and branched carbohydrates
What is ligin and where is it found?
reinforces secondary walls in woody plants
What is the middle lamella
hold primary and secondary walls via pectin
What is plasmodesmata?
communication junctions in plant cells
allow ions and molecules to move directly from one cell to another through via cytosol
Where are plasmodesmata located?
primary and secondary cell walls
What are the three animal cell surfaces specailized structures?
cell adhesion molecures, cell junctions, extracellular matrix
What do cell adhesion molecues do?
bind cells together
What do cell junctions do?
seal spaces between cells and allow for communication
What are cell adhesion molecules made of?
glycoprotiens in the plasma membrane
What happens to cancer cells in cell adhesion moelcues?
they lose thier adhesion allowing them to travel to new locations
What happens to cancer cells in cell adhesion moelcues?
they lose their adhesion allowing them to travel to new locations
what are anchrogin junctions?
weld adjacent cells together
What are desomosomes?
anchoring junctions with intermediate fillaments that anchor juntion in underlying cytoplasms
What are desomosomes?
anchoring junctions with intermediate filaments that anchor junction in underlying cytoplasms
What are adherens junctions?
microfilaments are the anchoring cytosletal component
How are tight junctions formed?
direct fusion of proteins on the outer surfaces of plasma membranes of adjacent cells
What is the outer suface called?
apical surface
What is the outer surface called?
apical surface
What are all junctions made of?
protiens
What is the channel between the gap junction called?
connexon
What are gap junctions?
open channels that allow ion and molecules to transfer between cells
What does the ECM contain?
proteins and polysaccarides
What is the function of ECM?
cell adhesion, etc
Where are integrins located?
plasma membrane
What are the main component of ECM
glycoprotiens
What is the most common glycoprotein in animal cells?
collagen
What are fibronectins?
bind to receptor proteins (integrins) in the plasma membrane, which bind to microfilaments of the cytoskeleton
glycoproteins in the ECM
What are proteoglycans?
that surrounds the collagen fibers - In bone, the network is impregnated with mineral crystals, producing a structure that is dense and hard, yet elastic
protein bound to lot of sugar residues, determines consistency of ECM
What are anchoring junctions made of?
desmosomes
What is a stack of thylakoids called?
grana
What do dyneins and kinesisn push/pull agains?
microtubles
What do myosins push/pull against?
microfilaments
What are plant gap junctions?
plasmodesmata
What type of junctions cover internal organs?
tight junctions
What are integrins?
Receptor proteins located in the plasma membrane
Bind microfilaments of the cytoskeleton
What links the ECM to the cytoskeleton?
fibronectins and integrins
In the Frye-Edidin Experiment was were the Human cell anti-bodies color?
red
In the Frye-Edidin Experiment was were the mouse cell anti-bodies color?
green
What does “fluid” refer to the in the Fluid mosaic model?
phospholipids
Which filament type is responsible for dividing the cytoplasm during the cytokinesis part of cell division?
microfilaments
What does two cysteine create?
cystine
