Exam 1 + 2 Material Flashcards
(46 cards)
1
Q
Flippase
A
Maintains ASYMMETRY between leaflets of the plasma membrane (charges
2
Q
Scramblase
A
Maintains SYMMETRY between leaflets of ER membrane
3
Q
Protein modifications to regulate chromatin structure
A
- Methylation of lysine (neutral)
- Acetylation of lysine (+)
- Phosphorylation of serine (-)
4
Q
Functions of Golgi Apparatus
A
- Central sorting center for proteins
- Attachment of O-linked carbohydrates to proteins
- Modification of N-linked glycosylation on proteins
5
Q
Functions of ER
A
- Attachment of N-linked carbohydrates to proteins
- Calcium storage
- Lipid synthesis
6
Q
Molecules with charge in a solution
A
- Phosphatidylserine
- Amino acids
7
Q
Molecules with NO charge in a solution
A
Sugars (monosaccharides)
8
Q
Where is phosphatidylserine found
A
Inner leaflet
9
Q
Where is phosphatidylcholine found
A
Both leaflets
10
Q
Differences between eukaryotes and prokaryotes
A
- Eukaryotes: linear cells, nucleus, internal membrane, telomeres, multiple origins of replications, introns
- Prokaryotes: circular cells, no nucleus, no internal membrane, no telomers, one origin of replication, no introns
11
Q
Sterols
A
Contains a rigid structure that stiffens phospholipids
12
Q
Types of sterols
A
- Animal: cholesterol
- Fungi: ergosterol
- Plants: phytosterol
13
Q
Plant cell wall components
A
- Cellulose provides tensile strength
- Tensin provides resistance to compression
- Lignin provides waterproofing
- Turgor pressure allows water to move inside the cell to build up internal pressure and prevent them from wilting against gravity
14
Q
Nuclear lamina
A
- Provide structural support
- Site for chromosome attachment during interphase
- Mutations can cause diseases such as Progeria
15
Q
Nuclear intermembrane space
A
Continuous with ER lumenal space (not mitochondrial)
16
Q
Nuclear pores
A
Allows small molecules to diffuse freely into the nucleus but large molecules require active transport
17
Q
Nucleolus
A
Site of ribosome assembly
18
Q
Resolution vs. Magnification
A
- Resolution is the ability to distinguish 2 objects that are close to each other
- Magnification is the ability to make an object appear larger/smaller but it will still be blurry
19
Q
Hydrophobic force
A
- Effect of entropy as a result of hydrogen bonding of the polar head groups being attracted to water
- The hydrogen bonds increase entropy
20
Q
Endosymbiont theory organelles
A
- Mitochondria
- Chloroplasts
21
Q
Mitochondria endosymbiont theory
A
- Has 2 membranes
- Contains ribosomes
- Has circular mDNA
- This shows it was a prokaryotic cell that was engulfed by a eukaryotic cell
22
Q
Heterochromatin features
A
- Highly condensed
- Can silence genes
23
Q
Structures in heterochromatin
A
Centromeres and telomeres
24
Q
Euchromatin features
A
Less condensed than heterochromatin
25
Structures in euchromatin
- Accessible to RNA transcription machinery
- Ex. RNA polymerase
26
Ribosome function
Protein synthesis
27
What are two sugars linked by
Oxygen
28
Electron microscopy
- Higher resolution compared to light microscopy
- Cells must be fixed (Cannot see living cells)
- Cannot see color
29
Light microscopy
- Can visualize living cells
- Can see different colors
- Limited resolution
30
Scanned electron microscopy
Can only see the EXTERNAL surface of a cell
31
Transmission electron microscopy
Can only see the INTERNAL surface of a cell
32
Fluorescence microscopy
- Absorb light at one wavelength
- Emit light at a longer wavelength
- Can visualize small cells
33
Confocal microscopy
- Uses scanning laser and pinhole apertures to limit detection in a focal plane
- Useful for obtaining 3D imaging
34
Resolution ranking
- DIC
- Green
- Red
35
Fluid Mosaic Model
- NOT continuous with the nucleus
- Fluid because molecules move freely past each other via lateral diffusion
- Mosaic because it contains discrete units that contain microdomains such as lipid rafts
- Phospholipids maintain lateral movements due to high levels of cholesterol
- Lipids can diffuse freely within a microdomain but are limited with neighboring microdomains
36
Lipid rafts
- Consists of lipids, proteins, and other molecules that act as discrete units
- Help with cell signaling and protein movement
37
Biomolecules that are polymers
- Carbs
- Proteins
- Nucleic acids
38
Carbohydrate monomers and functions
- Monomer: monosaccharide
- Store energy
- Provide structural support for a membrane
39
Protein monomers and functions
- Monomer: Amino acids
- Use their R-groups to interact with their environment
- Maintain cell communication
- Perform most cellular function
40
Nucleic Acid monomers and functions
- Monomer: Nucleotides
- Short-term energy storage
- Carry genetic information
41
Lipids
- Composed of fatty acids linked to glycerol
- Energy storage
- Assemble into membranes
42
Central Dogma
DNA > RNA > Proteins
43
Spontaneous Reactions
- Increase entropy in a system by releasing energy
- Useable energy decreases in these reactions
- Spontaneous reactions are favored
44
Second law of Thermodynamics and Cells
- Cells want to increase order to survive, so they need to expend energy to reduce entropy
- The second law states that processes are driven to increase entropy, which applies to closed systems
- Although cells are in open systems, they do NOT violate this law cells release heat into the universe which increases entropy
45
N-linked glycosylation
- Attaches oligosaccharide to NH2 groups on asparagine
- Can attach to multiple at the same time
46
O-linked glycosylation
- Attaches oligosaccharide to an OH group on serin and threonine
- Can only attach one at a time
