cells Flashcards
According to our study, what is the most significant limitation to cell size?
SA:V, cells needs to be able to transport materials and waste in/out of cell membrane so it can’t be too small or too large
Parts of the cell membrane and function
phospholipid bilayer- regulating traffic in and out of cell
intrinsic proteins- movement of molecules and signals
extrinsic proteins - transport of molecules and receptors
cholestrol - holds things in place
Light microscope vs. electron microscope, consider function of each, distinction between the two, advantages and disadvantages.
light microscope you can see living things but only in visible light
electron microscope can see organism better but only if their dead
Parts of the prokaryotic cell and function
mesosome - aids in cellular respiration
capsule/sheath - prevents cell from dying
nucleoid - contains most/all of genetic material
chromataphore - infolding that contains chloroplasts - controls color of cell
Prokaryotes…
-lack a nucleus, and generally lack independent, membrane-bound organelles
-circular DNA with no associated histone proteins,
-produce proteins that begin with formylmethionine rather than methionine
-lack a cytoskeletal matrix (microtubules and microfilaments).
Prokaryotes have
no nucleus,
-mesosomes rather than mitochondria
-no double membrane-bound organelles
-chromatophore rather than chloroplasts
-cell wall composed of peptidoglycan rather than cellulose.
According to Rudolf Virchow’s assertions in the Cell Theory, what could not be true?
spontaneous generation
endocytosis vs. exocytosis
endo: enter
exo: exit
pincytosis vs. phagocytosis.
pincytosis: inward invagination / ingestion (infolding of membrane surrounds the thing)
phagocytosis: if flexible free membrane, there’s cytoplasm streaming and sends pseudopods (foot) to engulf something
Function of the nucleolus?
ribosome synthesis
Pores of the nuclear envelope prevent the movement of ___ through the envelope while allowing ___ to move freely out of the nucleus.
dna, rna
The site of cellular respiration in the eukaryotic cell
mitochondrian
Proteins that are to be transported from the cell are
synthesized on ribosomes attached to the endoplasmic reticulum which packages the proteins produced in a membrane, allowing the resulting vesicles to fuse with other membranes, including the cell membrane.
Plastids that are specialized for the storage of (sugars?) vs. those involved in photosynthesis.
chloroplasts: use color to attract pollinators
leukoplasts & amiloplasts: store sugars and provide smell to attract pollinators
Nuclear proteins and RNA pass into and from the nucleus by means of
nuclear pores
Chromatin vs. chromosomes.
chromatin - loose diffuse dna
chromosomes - supercoiled DNA forming compact units
Which eukaryotic membrane-bound organelles are believed to have evolved from prokaryotic cells?
mitochondria and plastids
typically, eukaryotic cells
-are larger than prokaryotic cells
-contain many membrane bound organelles
-contain linear dna with associated proteins
-posses membrane surrounded nucleus
-use cytoplasmic protein-fiber framework for internal support
The energy produced by the mitochondrion is in the form of:
ATP
Which sub-cellular organelles are among those belonging to the endomembrane system?
everything except mitochondria, plastids, ribosomes, centrioles
What organelles are found in plant cells but not in animal cells? Animal cells but not plant cells?
plant- chloroplasts
animal-
what do centrioles form for cilia and flagella?
basal body
Most of the negative charge inside of cells is attributable to what?
cellular proteins
Associated with the cell membrane, these molecules act to transport materials through the membrane.
intrinsic/integral proteins
The process by which energy is released in the mitochondrion.
cellular respiration
Organelle composed of stacks of flattened cavities, functions in the modification of proteins for export.
golgi apparatus
what may have Mitochondria and plastids originated as?
independent prokaryotes taken into an early eukaryote by endocytosis
what may play a key role in providing stability to the plasma membrane?
cholesterol
Microtubules and microfilaments
may serve to provide a scaffold or matrix within the cell holding organelles in place in an otherwise fluid cytoplasm.
prokaryotic DNA is
naked and circular with very little associated protein
Anton van Leeuwenhoek’s great contribution to the Cell Theory is that he…
observed living, single-celled organisms using a compound microscope.
Robert Hooke observed the…
compartmentalization of tissue in a sample of cork and called the compartments cells.
hooke contribution to cell theory
compartmentalization of tissue: cells
van leeuwenhoek contributions to science
living single celled organism
schleiden and schwann contribution to science
living composed of cells
rudolf virchow contributions to science
cells come from preexisting cells
he rejects spontaneous generation
what is resolving power?
ability to distinguish between 2 objects
higher resolving power=better distinguishing power
what is fluid mosaic model?
phospholipid bilayer had proteins floating
proteins typically don’t move because cholesterol in tails provides stability
what does DNA supercoil on?
histoproteins
prokaryote vs eukaryote
prokaryotes have no nucleus eukaryotes have nucleus
how is golgi apparatus created and what does it create
vesicles pinch off to form golgi apparatus
vesicles pinch off of golgi apparatus to create functional proteins
where do mitochondria and plastids come from
Plastids and mitochondria may have evolved from prokaryotic symbionts living inside ancient eukaryotic cells.
