Flashcards in science: chpt. 7 test Deck (20)
___________ prevents fatty-acid tails from sticking together
In the mid _____ there was a lot of new _______ about cells because of the new ____________.
1800s; theories; microscopes
What did scientist observe using early microscopes?
Electron microscopes have about ____ more magnification than compound light microscopes
What king of images can be seen with a scanning electron microscopes (SEM)
What is the cell theory?
(1) All living organisms are composed of one or more cells
(2) Cells are the basic unit of structure and organization of all living organisms
(3) Cells arise only from previously existing cells, with cells passing copies of their genetic material on to their daughter cells.
What decade did the cell theory become a living thing?
Do bacteria cells have nuclei? Why?
No, because they are prokaryotic
What is present in eukaryotic cells?
Is cholesterol polar or non-polar?
What substance in the plasma membrane identify chemical signals?
What converts sugars into energy (also called the powerhouse of the cell)?
What organelles are only found in animals?
The condition of continuous, random movement of particles but no overall change in concentration of materials
Does active transport move substances with or against the concentration gradient?
What will happen to a cell in a hypotonic solution solution?
-Plant cells will swell but because of the cell wall it won't burst.
-Animal cells will swell and possibly burst.
What kind of molecules are expelled during exocytosis?
Is facilitated diffusion active or passive?
Compare and contrast exocytosis and endocytosis.
Both exocytosis and endocytosis are energy-requiring processes. However, exocytosis expels wastes and secretes substances at the plasma membrane and endocytosis is when large substances from the outside environment enter the cell.