Cell Structure and Functions Flashcards
What are the three general cell requirements?
Genetic Material, Cytoplasm, and Plasma Membrane
What is the genetic material in prokaryotes?
A single circular molecule of DNA
What is the genetic material in eukaryotes?
Double helix located in the nucleus
This fills the interior of the cell.
Cytoplasm
What can be found in the cytoplasm?
Sugars, Amino Acids, Proteins
This encloses the cell (phospholipid bilayer).
Plasma Membrane
Why are cells small in size?
For smaller surface area-to-volume ratio resulting in quicker rate of metabolism
Who classified cells on the basis of the presence of the nucleus?
Dougherty (1967)
These are cells without a nucleus.
Prokaryotes/Prokaryotic Cells
Etymology of Prokaryotes
“pro-“ meaning before and “-karyon” meaning nucleus
Etymology of Eukaryotes
“eu-“ meaning true and “-karyon” meaning nucleus
These are cells with true or distinct nucleus.
Eukaryotes/Eukaryotic Cells
What is Svedberg?
A non-metric unit
How do prokaryotes reproduce?
Binary Fission
How do eukaryotes reproduce?
Sexual/Asexual
What is the difference between the cell division of prokaryotes and eukaryotes?
Prokaryotes - chromosomes are pulled apart by attachment to the plasma membrane
Eukaryotes - by cytoskeletal spindle apparatus
What is the difference between the metabolism of prokaryotes and eukaryotes?
Prokaryotes - anaerobic or aerobic
Eukaryotes - Aerobic
This has circular DNA and are not associated with histones.
Prokaryotes
This has linear DNA and are associated with histones.
Eukaryotes
What is the cell size of prokaryotes?
1-10 micrometers
What is the cell size of eukaryotes?
10-100 micrometers
In this type of cell, RNA and protein synthesis occur in the same compartment.
Prokaryotes
In this type of cell, RNA is synthesizes in the nucleus while proteins in the cytoplasm.
Eukaryotes
This has no cytoskeleton, no cytoplasmic streaming, and no exo/endocytosis.
Prokaryotes
This model shows the “sandwich” arrangement of the cell membrane.
The Davson-Danielli Model
This is another name for the cell membrane.
Plasmalemma
What are the major functions of the plasmalemma?
Material exchange regulation and protection from external and unwanted materials
These are elastic double layers of phospholipids and fatty materials that form special surfaces over almost all subcellular organelles as well as over entire cells.
Plasmalemma
This is the E-face in the Fluid-Mosaic Model of the cell membrane.
Side of the membrane facing the extracellular matrix
Two glycocalyces found in the Fluid-Mosaic Model of the cell membrane
Glycoproteins and Glycolipids
This is the P-face in the Fluid-Mosaic Model of the cell membrane.
Side of the membrane facing the protoplasm
What are the six functions of the cell membrane?
1) Transport; 2) Enzymatic Activity; 3) Signal Transduction; 4) Cell-cell Recognition; 5) Intercellular Joining; and 6) Attachment to the Cytoskeleton and Extracellular Matrix (ECM)
Why is the cell membrane not liquid?
It won’t have shape if it is liquid.
Why is the cell membrane not solid?
It’ll have a fixed structure and transport will not be permissible.
Lateral diffusion is _______, while transverse diffusion is _______.
Rapid; Very Slow
What are the factors affecting the fluidity of the cell membrane?
1) Shorter hydrocarbon tails = greater fluidity; 2) Cis double bonds in tails lead to kinks and increase fluidity; and 3) Presence of cholesterol
