History Flashcards
1
Q
CRISPR/Cas9
A
- 2012
- Jennifer Doudna and Emmanuelle Charpentier at UC Berkeley
-Fenn Zhang - Harvard/MIT
2
Q
Synthetic biology
A
-Craig venter
3
Q
Modern cell biology
A
-combination of genetics, biochemistry, cytology
4
Q
Microscopes
A
- 1660
- Robert Hooke
- first microscope only had 30x magnification
5
Q
Antonie Van Leeuwenhoek
A
- 1670
- next microscope
- could magnify 300x
6
Q
Cell Theory
A
- 1838, 1839
- Schleiden and Shwann
- all organisms consist of one or more cells
- the cell is the basic unit of structure for all organisms
- 1885
- Virchow added that cells arise by division from pre-existing cells
7
Q
Prokaryotic
A
- bacteria, archaea
- evolved earlier than eukaryotes
- no membrane-bound nucleus (nucleoid instead)
- circular chromosomal DNA
- cytoplasm mostly devoid of membranous structures
- 1-5 micrometers
8
Q
Archaea
A
- methanogens )energy from hydrogen, converts CO2 to methane)
- halophiles (thrive in salty environments)
- thermacidophiles (live in acidic hot springs)
-archaea are more closely related to humans than bacteria
9
Q
Eukaryotic cells
A
- protists, yeast, fungi, plants, animals
- bigger than prokaryotes 10-100micrometer
- evolved more recently
- linear chromosomes
- compartmentalized organelles
10
Q
Common features between prokaryotes and eukaryotes
A
- plasma membrane
- genetic information uses identical code
- some shared metabolic pathways (glycolysis)
- similar mechanism to make ATP
- similar mechanism for photosynthesis
- similar proteasomes (protein digesting structures)
- some similarities in cytoskeleton features
11
Q
Measurements
A
- 1000 micrometer = 1mm
- 1000 nanometer = 1micrometer
- 10Å = 1 nanometer (approx diameter of H atom)
- entire cells or large organelles measured in micrometers
- most other cells structures measured in nanometers
12
Q
Electron microscopes
A
- focuses a beam of electrons on or through a specimen
- transmission EM
- Scanning EM
13
Q
TEM
A
- transmission electron microscope
- penetrates through specimen to show organelles
14
Q
SEM
A
- scanning electron microscope
- scans surface of specimen to give a 3D image
15
Q
Why does a cell have to be so small
A
- surface area:volume ratio
- diffusion rates of molecules
- need for adequate local concentrations of reactants and catalysts
16
Q
Cell biology is reductionist
A
-analyzing things and describing complex phenomenon in terms of its simple or fundamental constituents
17
Q
Possible Spontaneous synthesis of biological materials ???
A
- 1952: biochemists Harold Urey and Stanley Miller
- mixed water vapour, methane, ammonia, hydrogen gasses in seals glass apparatus
- essentially recreating early earth atmosphere
- a few weeks later = organic compounds including amino acids and carbohydrates collected
- so yes, these conditions could lead to spontaneous life
- considered the classic experiment on abiogenesis
18
Q
Endosymbiont theory
A
- one smaller cell engulfed in a larger cell to create double membrane
- Lynn margulis
- 1967
