eukaryotic and prokaryotic Flashcards
What does Cell theory state?
-The cell is the smallest unit of life
-All living things are made of ONE or MORE cells
-All new cells come from preexisting cells
Cell size:
-is limited
-Most rely on diffusion of substances in
and out of cell
Diffusion is affected by:
* Surface area available
* Temperature
* Concentration gradient
* Distance
What is diffusion of substances in
and out of cell
The cell regulates the entry and exit of substances through its plasma membrane.
-IN: oxygen, water, nutrients
-OUT: Carbon dioxide, waste, products (protein)
As ↑ radius of a cell goes up, what happens to the SA: V?
↓SA:V
Are larger or smaller cells more efficient?
smaller units are more efficient!
Is a larger SA:V for a cell good or bad? and why?
Larger SA:V means that the cell is
more efficient
* For every unit of volume there
are more units of membrane
that can “suck” up nutrients or
get rid of waste
* Metabolic needs set the upper
limits on the size of cells
What do ALL cells have?
Plasma membrane
* Cytoplasm
* Semifluid substance called cytosol
* DNA: chromosome(s) (carry genes)
* Ribosomes (make proteins)
Prokaryotic cells, types, differences, where is DNA located?
Bacteria and Archaea
* No nucleus
* DNA in unbound region called the nucleoid region
* No membrane-bound
organelles
Prokaryotic cells
* Inside plasma membrane: functions
- Cytoplasm: region of the cell that is contained within the plasma membrane
- Nucleoid region: location of DNA
- Ribosomes: protein synthesizers
Prokaryotic cells
* Outside the plasma membrane: functions
Cell wall: provides support and protection
* Glycocalyx: outer viscous covering
-Appendages
* Pili: attachment to other bacteria cells
* Flagella: movement
Prokaryotic cells
- Where does DNA replication, transcription (DNA as template to make RNA), translation
(RNA used as template to make protein) takes place in Prokaryotic cells?
- All take place in the same compartment!!
Where is the DNA located in Eukaryotic cells?
Nucleus
Are Eukaryotic cells in plants or animals?
Both, including fungi, and protists
Cytosol
Inside plasma membrane BUT region of eukaryotic cells that is outside
organelles
Cytoplasm
Everything inside the plasma membrane, including cytosol
Cytoskeleton
* Function:
Supports and
maintains cell shape
* Holds organelles in
position
* Moves organelles
* Involved in
cytoplasmic
streaming
* Interacts with
extracellular
structures to anchor
cell in place
What are the three main fibers of cytoskeleton?
Actin filaments
(microfilaments)
Microtubules (tubulin
polymers)
Intermediate filaments
Microfilament functions?
(Actin)
two intertwined strands of Actin
-Maintenace of cell shape
-muscle contraction
-cytoplasmic streaming in plant cells
-cell division in animal cells
Microtubules (tubulin
polymers) functions?
-Maintenace of cell shape
helps with CELL DIVISION
-biggest from the 3
Intermediate filament functions?
-Maintenace of cell shape
-anchoring age of nucleus and certain other organelles
-formation of nuclear lamina
How do Motor proteins interact with cytoskeletal filaments to
promote movement?
Use ATP as a source of energy for
movement
ATP structure:
Adenosine, ribosome, triphosphate
What are the Three domains of motor proteins?
head, hinge, and tail
Network of membrane enclosing system list:
- Nuclear envelope
- Endoplasmic reticulum
- Golgi apparatus
- Lysosomes
- Vacuoles
List the Endomembrane system major function
Protein exportation/sorting
What is the Nuclear envelope?
*Encloses nucleus
* Double membrane
* Outer membrane continuous
with ER membrane
* Nuclear pores: regulates entry
and exit of molecules
Nucleus function:
- Protection, organization, replication
- Expression of genetic material
- Assembly of ribosome subunits
Chromosome
composed of genetic
material
Chromatin
complex formed
between DNA and proteins that
help compact chromosomes
Nuclear matrix
has a Nuclear lamina: both provides structure to
nucleus
* Internal nuclear matrix
Nucleolus
Site of ribosome assembly
Cisternae
Flattened, fluid-filled tubules made from a network of membranes that makes up Endoplasmic reticulum
Rough endoplasmic reticulum
Studded with ribosomes
* Functions:
* Sorting proteins
* Synthesizing proteins
* Glycosylating proteins and lipids
* Attachment of carbohydrates to proteins
and lipids
Smooth endoplasmic reticulum
Little to no ribosomes
* Functions in diverse metabolic processes:
* Carbohydrate metabolism
* Accumulation Ca2+
* Synthesis and modification of lipids
* Detoxifies drugs and poisons
Golgi apparatus, structure and function
Stack of flattened,
membrane bound
compartments:
Cis, Medial, Trans
Functions:
Directs the processing of
molecules from the ER, protein processing
Lysosomes
Involved in intracellular digestion of
macromolecules
* Contain: acid hydrolases
* Break down polymers
into monomers
* Requires water
* Function optimally at acidic pH
Vacuoles: function and types
Function: storage, regulation of
cell volume, and degradation
* Types:
* Central vacuole
* Contractile vacuole
* Degradation
Peroxisomes: structure and function
Single membrane, fluid-filled lumen
* Functions:
* Breakdown organic molecules
* Catalyze detoxifying reactions
Semiautonomous organelles are…
Mitochondria and chloroplasts
Semiautonomous organelles function
- Contain own DNA
- Depend on the cell for synthesis of
internal components - Grow and divide to reproduce
themselves
Mitochondrial function
make ATP
Cellular respiration
metabolic process that uses oxygen to
make ATP
Chloroplast; function and structure
Carry out photosynthesis
* Structure
* Membranes:
* Inner membrane
* Outer membrane
* Thylakoid membrane
mitochondrion and chloroplast derived from what?
- Mitochondria were derived from purple
bacteria - Chloroplasts were derived from
cyanobacteria - A photosynthetic blue-green bacteria
Endosymbiosis theory
Inner membranes of chloroplasts and mitochondria are similar to plasma
membranes of prokaryotes
* Division of chloroplasts and mitochondria is similar in these organelles and
some prokaryotes
Endosymbiosis theory
* DNA structure of chloroplasts and
mitochondria is similar to that of
prokaryotes
* Chloroplasts and mitochondria
transcribe and translate their
own DNA
* Chloroplast and mitochondrial
ribosomes are more similar to
prokaryotic ribosomes than
eukaryotic ribosomes
The different Sorting signals of proteins
- No signal
- Cotranslational sorting
- Post-translational sorting
No signal process
stays in cytosol
cotranslational
sorting
Proteins with the final destination of ER, Golgi, lysosomes, vacuoles,
plasma membrane, or section follow cotranslational sorting
post-translational
sorting
Proteins with the final destination of nucleus, peroxisomes, mitochondria,
or chloroplasts follow post-translational sorting
