Ch.3 Part.2 Flashcards
What is passive diffusion?
-No energy required
-down the concentration gradient
-diffusion
what is diffusion?
-moves down their electrochemical gradient through the phospholipid bilayer of the membrane
-only small molecules or lipid-soluble
what is facilitated diffusion?
-needs a nonspecific channel protein
-need an integral protein to “facilitate” movement
what is osmosis?
water molecules move down their concentration gradient across a selectively permeable membrane
what are the principle of Passive diffusion?
1.) diffusion
2.) nonspecific facilitated diffusion
3.) specific facilitated diffusion
4.) osmosis
what is a solvent
water
what is a solute
dissolved chemical
how does osmosis flow?
flows from the region of highest concentration to lowest
what is isotonic
equal
what is hypertonic
the solution has more solute
what is hypotonic
the solution has less solute
cells are typically what
hypertonic to their environment
in osmosis, cells are typically what
hypertonic to their environment
what does active transport use
utilizes a transmembrane protein (ATPase) to allow a molecule to gO AGAINST the concentration gradient
what are the 3 types of active transport?
Uniport
symport
antiport
what is group translocation (in active transport)?
the molecules being transported across the membrane are chemically altered during transport
what is group translocation common with?
sugars: glucose to glucose-6-phosphate (CH2OPO4)
what is active transport?
ATP-dependent carrier proteins bring substances into cell
what is a cytosol
-liquid and dissolved substances; mostly water
-site of a chemical reaction within the cell
what is inclusion
-not membrane-bound
-storage-can contain deposits (minerals, sugars, etc)
-can be diagnostic
what is a cytoskeleton
-composed of 3-4 types of protein fibers
-many roles within the cell: cell division, shape, segregate DNA molecules, movement
describe ribosomes
-70S
-composed of polypeptides and ribosomal RNA (rRNA)
-no membrane
-site of protein synthesis
what is an endospore
unique structure produced by some bacteria (bacillus and clostridium)
-defense against unfavorable conditions
-state of suspended animation
-resistant to heat, drying, radiation, chemicals
-major problem for food processing, healthcare and government
Describe the domain archaea
-prokaryote
-very diverse group
-resemble bacteria in many ways
-grow in extreme environments (extremophile)
-hard to grow in a lab environment
-none are known to cause disease
