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What are the seven components of the modern day cell theory?
1. All
known living things are made up of one or more cells
2. All living cells arise from pre-existing cells by division.
3 The cell is the fundamental unit of structure and function in all living
organisms.
4. The activity of an organism depends on the total activity of independent
cells.
5. Energy flow (metabolism and biochemistry) occurs within cells.
6. Cells contain DNA which is found specifically in the chromosome and RNA
found in the cell nucleus and cytoplasm.
7. All cells are basically the same in chemical composition in organisms of
similar species
A scientist wants to detach a peripheral membrane protein
from the exterior of a cell membrane. Which is the best method to do so?
A. change salt concentrations
B. Perform a light centrifuge
C. Add a detergent
D. Change the temperature of a solution
E. Run a small current through the solution
A.
change salt concentration
Peripheral membrane proteins are held in place by electrostatic interactions
and hydrogen bonding. They are generally hydrophilic. Changing the salt
concentration (a "salt wash") or the pH would disrupt both of these
types of bonds and release the peripheral membrane protein from the cell
membrane. A light centrifuge will precipitate cells and nuclei at most, only
heavy centrifuges extract small soluble proteins.
All of the following were observed by Miller-Urey in their
classic experiment to check the hypothesis of the "chemical origins of
life" EXCEPT for one. Which one is the EXCEPTION?
A. Methane
B. Amino acids
C. Ammonia
D. Organic compounds
E. Nucleic acids
Nucleic
acids
What was the Miller-Urey experiment
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