Organelles Flashcards
1
Q
Does a prokaryote have a nucleus?
A
No
2
Q
What is the diameter of a typical prokaryote cell?
A
1 um
3
Q
What is the diameter of a typical eukaryote cell?
A
10-100 um
4
Q
Does a prokaryote cell have a cytoskeleton?
A
No
5
Q
Does prokaryote have cytoplasmic organelles?
A
No
6
Q
Prokaryote cells have ______ ______ DNA
A
Single Cirulcar
7
Q
Eukaryote cells have ______ ______ DNA
A
multiple linear
8
Q
Walls of prokaryotes are made of?
A
Carbohydrate (peptidoglycan)
9
Q
RER is responsible for _____ production
A
protein
10
Q
SER is responsible for _____ production
A
lipid
11
Q
What gives membranes their shape?
A
microfilaments
12
Q
What is the backbone of all membranes?
A
phospholipid bilayer
13
Q
How does cholesterol affect a membrane?
A
It increases the rigidity
14
Q
Cholesterol has a ______ head
A
hydrophilic
15
Q
Glycolipid is a phospholipid with ______ attached sugar chains
A
covalently
16
Q
What kind of chains only face the extracellular surface?
A
Carbohydrate chains
17
Q
What is another name for integral protein?
A
Transmembrane protein
18
Q
What color will gram-negative prokaryotes stain?
A
Pink
19
Q
What color will gram-positive prokaryotes stain?
A
Purple
20
Q
Explain why some prokaryotes will stain pink and some purple
A
Gram negative bacteria has to membranes, (outer membrane, then cell wall, then plasma membrane) so the stain can’t get through the wall. Gram positive bacteria only has one plasma membrane (a cell wall on top) so stain binds to carbohydrates in cell wall and it stains purple
21
Q
What is glycocalyx?
A
The name of carbohydrates on eukaryotic surface
22
Q
What cannot cross a cell membrane unless they are transported through channels or transporters?
A
Anything hydrophilic (can’t cross the hydrophobic part of bilayer)
23
Q
A vacoule is responsible for?
A
Water storage
24
Q
What is responsible for the synthesis of ribosomal RNA?
A
nucleolus
25
What is responsible for DNA replication, synthesis of tRNA, mRNA, and some nuclear proteins?
Nucleus
26
Where does glycolysis, and many reactions in gluconeogenesis take place?
Cytosol
27
Where does pentose phosphate pathways, activation of a.a., fatty acid synthesis, and nucleotide synthesis take place?
Cytosol
28
Where does glycogen synthesis and degradation take place?
Glycogen granules
29
What are lysosomes responsible for?
Segregation of hydrolytic enzymes such as ribonuclease and acid phosphatase
30
What is ER responsible for?
Lipid synthesis, direction of biosynthetic products to their ultimate location
31
What are ribosomes responsible for?
Protein synthesis
32
What is responsible for a.a. oxidation, catalse & perodiase reactions, sterol degradation?
Microbodies
33
What are the duties of the golgi complex?
Maturation of glycoproteins & other components of membranes and secretory vessels
34
Where does citric acid cycle, ETC, odiative phosphorylation, fatty acid oxidation, amino acid catabolism, pyruvate oxidation take place?
Mitochondria
35
Where does the inner leaflet of cell membrane face?
cytoplasm
36
Where does outer leaflet of cell membrane face?
extracellularly
37
Phospholipids, glycolipids, and cholesterol are all components of ____ _____
Cell membrane
38
Cholesterol is a type of _____
Steroid
39
Triglyceride store ____
fat
40
Phosphatidylcholine is an example of a ______
phospholipid
41
What does amphipathic mean?
has hydrophobic & hydrophillic parts
42
Describe structure of phospholipid
amphipathic, polar head and 2 non-polar tails (tails are made of carbon)
43
All lipids are ____
amphipathic
44
Is cholesterol found on the inner or outer leaflet?
both
45
Are glycolipids found on the inner or outer leaflet?
outer
46
glycolipid carbohydrate residues form ____
glycocalyx
47
A phospholipid has a polar head and two non-polar tails, what is important about the tails?
One is kinked (unsaturated, double bonds) and one is no kinked (saturated)
48
How does more kinks in a phosphlipid tail affect the cell membrane?
It makes it more fluid
49
How does less kinks in a phospholipid tail affect the cell membrane?
It makes it less fluid
50
Phosphatidic acid is an example of what?
Phospholipid
51
Phocholinesphatidyl is an example of what?
Phospholipid
52
Phosphatidyl-ethanolamine is an example of what?
Phospholipid
53
Phosphatidyl-serine is an example of what?
Phospholipid
54
Where is phosphatidyl-serine found and why?
It is usually found on inner membrane. When a cell is undergoing apoptosis, an enzyme will flip it to outer membrane, signaling to macrophages to engulf it
55
Phosphatidyl-inositol is an example of what?
Phospholipid
56
Sphingomyelin is an example of what?
Phospholipid
57
Where is sugar found on cell membrane?
On extracellular surface
58
A fatty acid will form what when dropped in water?
Micelle
59
A phospholipid will form what when dropped in water?
Bilayer
60
What is the name of a circular bilayer used for drug delivery?
Liposome
61
What kind of bonding holds the lipids in the membrane together?
van der Waals bonding b/w tails
62
In electron microscopy, the membrane appears ______ because the polar heads stain and the lipid section remains clear
trilaminar
63
Membrane ______ is essential for exocytosis, endocytosis, membrane trafficking & biogenesis
fluiditiy
64
Which part of cholesterol is hydrophilic?
Hydroxy Head Group
65
As there is in crease in temperature, what happens to membrane fluidity?
Fluidity increases
66
Unsaturated fatty acid tails do what to membrane fluidity?
Increase fluidity
67
Cholesterol does what to membrane fluidity?
Make membrane more stable or rigid
68
What happens to red blood cells if there is too much cholesterol?
Because cholesterol makes membrane more rigid, cells have a distorted shape. RBC have thorn/finger like projections. Flexibility very important to function of RBC!
69
What is ascites?
A protruding abdomen
70
What is Asterixis?
Hold out hand and it flaps
71
What is a reticulocyte?
an immature RBC
72
Why does haemolytic anemia occur?
RBC are being destroyed too quickly
73
What does caput medusae and oesophageal varices mean?
new blood vessels are being formed
74
What pathology is associated with chronic liver disease?
Acanthocytosis
75
What is acanthocytosis?
spur cells due to increased cholesterol in RBC membrane
76
In acanthocytosis, RBC are deformed due to high cholesterol levels. What happens in the spleen because of this?
They get trapped and destroyed too early in the spleen
77
A pt is jaundiced, has portal hypertension with ascites, asterixis, an increased reticulocyte count and distorted cholesterol balance - what do you suspect pt has?
Acanthocytosis
78
What is a glycosylphosphatidylinositol anchor (GPI)?
A glycolipid that attaches proteins to plasma membrane
79
Lipid rafts are rich in what two compounds?
cholesterol and glycosphingolipids
80
Where do GPI tend to be found?
Lipid rafts
81
____ _____ contain integral and peripheral membrane proteins, stick out of membrane a little, and are less fluid.
Lipid rafts
82
What can be covalently attached to a GPI?
protein
83
Why do lipid rafts contain integral and peripheral membrane proteins clustered together?
The clustering enables proteins to function together for endocytic vesicles
84
_____ use ATP to flip a phospholipid across a membrane
Flippase
85
What maintains the asymmetry of a membrane
flippases
86
Flippases are ________ specific
phospholipid
87
Scramblases are ______ scramblers
non-specific
88
What two enzymes do flip-flop in cell membrane?
Flippase and Scramblase
89
Is scramblase or flippase activated during apoptosis?
Scramblase
90
What is a phosphlipid with a covalently attached sugar chain?
glycolipid
91
What is on the surface of all plasma membranes?
Glycolipids
92
Glycolipid is only on the ____ ____ of plasma membrane
outer leaflet
93
A Ganglioside is an example of a
Glycolipid
94
What is ganglioside a receptor for and where is it found?
Receptor for cholera toxin, found on intestinal epithelial cells
95
The protein:lipid ratio is dependent on what?
What kind of cell it is
96
Integral proteins bound to ____ ______ help maintain the structural integrity of the plasma membrane
actin cytoskeleton
97
List the functions of membrane proteins
Transport nutrients, metabolites, and ions across bilayer
Anchor membrane to macromolecules on either side
Receptor: signal transduction
Enzymes
Cell identity markers (MHC)
98
What is 30% of total protein and is amphipathic, often with an alpha helical secondary protein structure?
Integral transmembrane protein
99
What is the function of integral transmembrane proteins?
Receptors - signaling and adhesion, channels, transporters/pumps
100
What are located entirely outside but associated with inner/outer leaflet by noncovalent interactions?
Peripheral proteins
101
Peripheral proteins are part of the ______
cytoskeleton
102
What is located on either side of the bilayer and has a lipid group that inserts into the bilayer?
Lipid-anchored (peripheral) protein
103
What is the function of lipid-anchored protein?
Signaling and cell adhesion
104
What are the two different types of lipid anchors?
GPI (Glycosylphosphatidylinositol) anchor & Acylation or prenylation anchor
105
Acylation links proteins to the _____ ______
inner leaflet
106
Prenylation links proteins to the ____ _____
inner leaflet
107
GPI links proteins to the ____ _____
outer leaflet
108
What are the two kinds of transmembrane proteins in RBC?
Band 3 & Glycophorin
109
Glycophorin is a ________ transmembrane protein
single pass
110
Band 3 is a ________ transmembrane protein
multipass
111
Spectrin is found in what kind of cell?
RBC
112
What kind of chains make up spectrin?
alpha and beta
113
What proteins bind to spectrin?
Band 3 & Glycophorin
114
What two things bind together and help keep integrity of spectrin/junctional complex
F-actin & protein 4.1
115
What is the purpose of spectrin in RBC?
Reinforces bilayer, allows RBC to withstand stress
116
What is the purpose of ankyrin?
attaches spectrin cytoskeleton to membrane
117
What does ankyrin bind to?
band 3
118
What does protein 4.1 bind to?
glycophorin, spectrin, band 3
119
Draw example blood cell membrane, including Glycophorin, Band 3 protein, Ankyrin, spectrin, Band 4.1, & actin
Check answer on organelle power point, slide 40
120
What is the major cause of hereditary Spherocytosis?
inherited mutation in spectrin
121
A very small, round blood cell that loses biconcave shape is called a _____
spherocyte
122
Why are spherocytes small and round?
spectrin has a defect so the membrane is not strong - when membrane goes through small spaces like capillaries the membrane ruptures and little parts of membrane come off.
123
If a person has spherocytes what kind of anemia might the have?
haemolytic
124
If a person has the following symptoms: haemolytic anemia, jaundice, gall stones, and round, small RBC, what disease might they have?
hereditary spherocytosis
125
What is splenomegaly?
Increased spleen size
126
Why do pts with Hereditary spherocytosis have splenomegaly?
the RBC get trapped in spleen causing the spleen size to increase
127
Apical, lateral, and basal are all examples of _______ proteins but they all have different ______
transmembrane, functions
128
What is the function of the apical plasma membrane (and proteins)?
regulation of nutrient and water intake, regulated secretion, protection
129
What is the function of the lateral plasma membrane (and proteins)?
cell contact & adhesion, cell communication
130
What is the function of the basal plasma membrane (and proteins)?
cell-substratum contact, generating ion gradients
131
What is the name of the sugar coat on all cells?
glycocalyx
132
The majority of proteoglycan is _____
sugar
133
The majority of glycoprotein is _____
protein
134
Name three general classes of carbohydrates in the cell membrane
glycoproteins, glycolipids, proteoglycans
135
Why do all cells have a glycocalyx coat (What is the function of glycocalyx)?
protection from acids, enzymes, etc
recognition (leukocyte) & cell adhesion
repulsion: negative charge from sialic acid sugars
embryonic development: guides embryonic cells to destination
136
Cancer cells have a different _____ coat than non cancer cells
glycocalyx (sugar!)
137
Some anti-cancer therapies target enzymes that assemble what to start an immune defense to attack the cancer cells?
tumour glycocalyx - the antibodies recognize and attack
138
What are the primary marker for cell recognition?
carbohydrates
139
What are selectins?
a group of proteins that bind to the sugar chain of a glycoprotein instead of to the protein itself
140
What is the attachment for viruses, bacteria, toxins, and other cells?
carbohydrates
141
____ recognize addressins on lymphoid organ endothelial cells
L-selectins
