Chapters 6-7 Flashcards
1
Q
Endomembrane system
A
Endoplasmic reticulum, nuclear envelope, Golgi apparatus, lysosomes, and vesicles
2
Q
Central vacuole
A
Compartment for the storage of inorganic ions such as potassium and chloride
3
Q
Plasmodesmata
A
Cell junctions in plant cells
4
Q
Gap junctions
A
Communicating junctions in animal cells
5
Q
Centrosomes are composed of
A
Centrioles
Centromesomes are in animal cells
6
Q
The walls of plant cells are largely composed of polysaccharides and proteins that are synthesized
A
In the rough ER and the Golgi apparatus
7
Q
Basal bodies are most closely associated with
A
Cilia
8
Q
Which groups are primarily involved in synthesizing molecules needed by the cell?
A
Ribosomes, rough ER, smooth ER
9
Q
Glycoprotein
A
Proteins with covalently bonded carbohydrates
10
Q
Nucleoid
A
Region of a bacterial cell that contains genetic material
11
Q
In a eukaryotic cell, the DNA is in
A
The nucleus
12
Q
All of the following are functions of membrane proteins except Cell-cell recognition Protein synthesis Signal transduction Intercellular joining Transport
A
Protein synthesis
13
Q
According to the fluid mosaic model of membrane structure, proteins of the membrane are mostly
A
Embedded in a lipid bilayer
14
Q
Plasma membrane
Vesicles
A
Exchange with the environment
15
Q
Cilia
Flagella
A
Movement
16
Q
Desmosomes
Tight and gap junctions
Extracellular matrix
A
Cell-to-cell connections
17
Q
Cytoskeleton Microtubules Microfilaments Intermediate filaments ECM
A
Structural integrity
18
Q
Peroxisomes
A
Oxidation, conversion of H2O2 to water
19
Q
Lysosomes
Food vacuoles
A
Digestion
Recycling
20
Q
Smooth ER
A
Lipid synthesis
Drug detoxification
21
Q
Ribosomes
Rough/smooth ER
Golgi
Vesicles
A
Manufacture of proteins, membranes, and other products
22
Q
Mitochondria
Chloroplasts
A
Energy conversions
23
Q
Nucleus
Chromosomes
A
Information storage and transferral
DNA—mRNA—enzymes and other proteins
24
Q
Nucleus Chromosomes Centrioles Microtubules Microfilaments
A
Cell Division
25
Cytoskeleton is made of
Microtubules (thickest)
Microfilaments (actin filaments) (thinnest)
Intermediate filaments (middle range)
26
Aquaporins
Channel proteins that allow the passage of water molecules through the membrane
-facilitate the passage of water
27
If the stuff can't move
Water will!!
28
Diffusion
Movement of particles on any substances so that they spread out into available space
H-L
High concentration OF THAT MOLECULE to low concentration OF THAT MOLECULE
Molecules move based on its own solute concentration
29
Once all the stuff moves...
Then water will move because once the stuff moves, it changes the concentration of water
30
Everything moves
Down their concentration gradient
| And based on their own concentration
31
Concentration gradient
Region along which the density of a substance increases or decreases
-any substance will move down
32
Passive transport
Diffusion of a substance across a membrane
Does not require energy
H-L
33
Osmosis
Diffusion of WATER across a selectively permeable membrane
34
Isotonic
Same solute concentration
| Water diffuses across the membrane at the same rate in both directions
35
Hypertonic
More/higher solute concentration
Cell shrivels
Loses water, may die
36
Hypotonic
Less solute concentration
Water enters cell faster than it leaves
Cell will swell and burst (lyse)
37
Turgid
Very firm, healthy state for most plant cells
| Plant cell when in a hypotonic solution
38
Flaccid
Limp, when plant cells and their surroundings are isotonic
39
Plasmolysis
As plant cell shrivels, it's plasma/cell membrane pulls away from the cell wall at multiple places, causes plant to wilt and can cause death
40
Facilitated diffusion
Polar molecules and ions impeded by the lipid bilayer of the membrane diffuse passively w/ the help of transport proteins that span the membrane
PASSIVE
H-L
41
Sodium-Potassium pump
Transports sodium ions out of the cell and transports potassium ions into the cell
42
Active transport
L-H
Moving a solute against its gradient
Transport protein involved: carrier proteins because channels move solutes down their gradient
ATP supplies energy for the process
43
Proteins for:
Diffusion
Facilitated diffusion
Active transport
Diffusion: straight through membrane
Facilitated diffusion: channel and carrier proteins
Active transport: carrier protein
44
Membrane potential
| Which side of membrane is positive?
Voltage across a membrane
| Outside
45
Cations go
| Anions go
Into
| Out of
46
What two forces drive diffusion of ions across the membrane?
| What is combination of these forces called?
```
Chemical force (ion's concentration gradient)
Electrical force (effect of membrane's potential on environment)
Electrochemical gradient
```
47
Inside of cell is
| Outside of cell is
Negative
| Positive
48
Exocytosis
Cell secrets certain molecules by the fusion of vesicles with the plasma membrane
49
Endocytosis
Cell takes in molecules and matter by forming new vesicles from plasma membrane
3 types: phagocytosis, pinocytosis, receptor-mediated endocytosis
50
Receptor-mediated endocytosis
Form of pinocytosis
| Used to take in cholesterol in human cells
51
Phagocytosis
Cellular eating
52
Pinocytosis
Cellular drinking
53
Amphipathic
Has both a hydrophilic and hydrophobic region
54
Membrane fluidity
Movement in and out of a membrane, how membranes move
55
Fluid mosaic model
The membrane is a mosaic of protein molecules bobbing in a fluid bilayer of phospholipids
56
Integral proteins
Penetrate the hydrophobic interior of the lipid bilayer
| Both hydrophilic and hydrophobic
57
Peripheral proteins
Not embedded in lipid bilayer at all, appendages loosely bound to surface of the membrane, often exposed to integral proteins
58
Channel proteins
Function by having a hydrophilic channel that molecules or ions use as a tunnel through the membrane
59
Carrier proteins
Hold onto their passengers and change shape in a way that moves them across the membrane
60
Glycolipids
Covalently bonded to lipids (carbohydrates)
61
Glycoproteins
Carbohydrates covalently bonded to proteins
62
Transport protein
Channel across membrane
63
Enzymatic activity
Carries out steps of a metabolic pathway
64
Signal transduction
Receptor, signaling molecule
65
Cell-cell recognition
Identification tags
66
Intercellular joining
Hook together various kinds of junctions
67
Attachment to cytoskeleton and ECM
Noncovalently bound to membrane proteins
| Helps stabilize cell shape and stabilizes location of membrane proteins
68
Nucleus
Surrounded by nuclear
envelope
Contains chromosomes made of chromatin
69
Golgi apparatus
Cis/trans faces
| Modification of proteins, synthesis of polysaccharides, carbohydrates on proteins, phospholipids
70
Lysosomes
Breaks down ingested substances, cell macromolecules, and damaged organelles for recycling
71
Vacuole
Digests, stores, waste disposal, water balance, cell growth and protection
72
Centrioles
In centrosome
73
Nucleolus
Inside nucleus
| rRNA is synthesized from instructions in the DNA
74
Ribosomes
Made of rRNA and protein
75
Mitochondria
Cellular respiration
76
Peroxisomes
Contains enzymes that transfer hydrogen atoms from substances to oxygen
Produces H2O2
77
Microtubules
Thickest fiber that makes up cytoskeleton
| Maintains cell shape, cell motility, organelle movements, and chromosome movements in cell division
78
Cilia and Flagella
Microtubule containing extensions that project from some cells
Helps move cells
Anchored by basal body
79
Smooth ER
Synthesis of lipids, detoxification of drugs/poison
80
Rough ER
Aids in synthesis of secretory and other proteins from bound ribosomes, produces new membranes
81
Plastids (chromoplasts and leucoplasts)
Closely related organelles that includes chloroplasts, chromoplasts, and amyloplasts
82
Cytoskeleton
Network of fibers extending throughout cytoplasm
| Gives mechanical support to cell/maintains shape
83
Chloroplasts
Photosynthesis
84
Endomembrane system includes
```
Nuclear envelope
ER
Golgi
Lysosomes
Vacuoles
Plasma membrane
```
85
Endomembrane system
Nuclear envelope connected to rough ER, which is connected to smooth ER
Membranes and proteins produced by ER flow in the form of transport vesicles to the Golgi
Golgi punched off transport vesicles
Lysosome is now available for fusion with another vesicle for digestion
Transport vesicles carry proteins to plasma membrane for secretion
Proteins are secreted by the cell
86
Endosymbiotic theory
An early ancestor of eukaryotic cells engulfed an oxygen using non-photosynthetic prokaryotic cell. The host cell and its endosymbiont merged into a single organism-eukaryotic cell with a mitochondria. Evidence: mitochondria and chloroplasts have two membranes, contain ribosomes, as well as DNA molecules, and they are independent organelles that grow and reproduce inside a cell
87
Integral proteins
Penetrate the hydrophobic interior of the lipid bolster
88
Peripheral proteins
Not embedded in lipid bilayer at all, appendages loosely bound to surface of the membrane, often exposed to integral proteins
89
Channel proteins
Function by having a hydrophilic channel that molecules use as a tunnel through the membrane
90
Carrier proteins
Hold onto their passengers and change shape in a way that moves them across the membrane
91
Difference between animal and plant cells
Plant cells:
Cell wall
Chloroplasts
Large central vacuole
Plasmodesmata that pass through the cell walls
Animal cells:
Tight junctions, desmosomes, and gap junctions
Centrosome, intermediate filaments, and microvilli
92
How does the fluid mosaic model describe the structure of the plasma membrane?
Proteins in the membrane contribute to the mosaic quality of the membrane while the lateral and rotational movements of phospholipids contribute to its fluidity
