XI Chap 8 Cell: Unit of Life Flashcards
(337 cards)
1
Q
_________ emphasized the unity underlying the diversity in forms of biological organisms
A
Cell theory
2
Q
The physico-chemical approach to study of living organisms is called __________________
A
Reductionist Biology
3
Q
_______ was an outstanding figure in the field of protein structure and founder of the ‘Madras’ school of conformational analysis of biopolumers
A
G N Ramachandran
4
Q
____________ discovered the triple helical structure of collagen
A
G N Ramachandran
5
Q
G N Ramachandran was deeply influenced by ______’s publications on models of the alpha-helix and Beta-sheet structures
A
Linus Pauling
6
Q
______ is the basic unit of life in all organisms
A
Cell
7
Q
___________ organisms are capable of independent existence and performing the essential functions of life
A
Unicellular organisms
8
Q
_______ first saw and described a live cell
A
Anton Von Leeuwenhoek
9
Q
_________ discovered the nucleus
A
Robert Brown
10
Q
The invention of _________ and _________ revealed all the structural details of a cell
A
microscope and electron microscope
11
Q
In ______ a German botanist named _______ observed that all plants are composed of different kids of cells
A
1838, Matthias Schleiden
12
Q
In ________ a British Zoologist _________ studied animal cells and reported that cells had a thin outer layer today known as _________
A
1839,
Theodore Schwann,
plasma membrane
13
Q
_________ concluded that the presence of cell wall is unique to plant cells
A
Theodore Schwann
14
Q
Theodore Schwann proposed what hypothesis?
A
that the bodies of animals and plants are composed of cells and products of cells
15
Q
_______ and _______ together formulated cell theory, What was lacking in this theory?
A
Schleiden and Schwann,
lacking - explanation for how new cells are formed
16
Q
_____________ explained for the first time in the year ______ that cells divided and new cells are formed from pre-existing ones
A
Rudolf Virchow, 1855
17
Q
What does omnis cellula-e cellula mean?
A
Every cell from the cell,
cells divide to form new cells
18
Q
What are the 2 tenets of cell theory?
A
- All living organisms are composed of cells and products of cells
- All cells arise from pre-existing cells
19
Q
What are the exceptions to cell theory?
A
Bacteria, Viruses, Sieve tube (enucleated), RBCs (enucleated), Rhizopus (multinucleated)
20
Q
Cells of human cheek have ________ as delimiting structure of the cell, whereas onion cell has ______
A
outer membrane, cell wall
21
Q
Cell is a ___________ that separates outer and inner environments so that _____________
A
chamber, reactions can continue unperturbed
22
Q
EVERY cell at some point has DNA which stores info for some reactions and processes inside the cell. T or F?
A
True.
Even RBCs and sieve cells first have DNA then lose it to become enucleated
23
Q
Cells that have membrane bound nuclei are called _____ whereas those that lack it are called _____
A
eukaryotic,
prokaryotic
24
Q
Cell membrane is made up of ___________ which makes it __________ (hydrophilic/hydrophobic)
A
lipid, hydrophobic
25
Only in eukaryotic cells with membrane bound nuclei, a semi-fluid matrix called cytoplasm occupies the volume of the cell. T or F?
False, in both eukaryotic and prokaryotic
26
Prokaryote and eukaryotic cells BOTH have organelles. T or F?
True, but prokaryotes have non-membrane bound organelles
27
Main arena of cellular activities in both plant and animal cells is _________
cytoplasm
28
Various chemical reactions in the cytoplasm of a cell keep it in a _________ state
living
29
In addition to a nucleus, eukaryotic cells have other membrane-bound structures called ______
organelles
30
Endoplasmic reticulum, golgi complex, lysosomes, mitochondria, microbodies and vacuoles are all examples of ______________
cell organelles
31
Prokaryotic cells lack membrane bound organelles. T or F?
True
32
Ribosomes are membrane-bound organelles found in all cells - eukaryotic and prokaryotic. T or F?
False, found in all cells yes but NON-membrane bound
33
Ribosomes are found where in the cell?
Cytoplasm, within chloroplasts (in plants), within mitochondria and on rough ER
(in bacteria - associated with plasma membrane)
34
What is centrosome?
Non-membrane bound organelle,
in animal cells,
helps in cell division
35
Cells differ greatly in ______, ______ and ______
size, shape and activities
36
___________ are the smallest cells only _____ in length
Mycoplasma, 0.3 µm (micrometer)
37
Mycoplasma has ______ (cell wall / no cell wall) and its shape is ________
no cell wall, not fixed
38
Length of bacteria is ________
3 to 5 µm
39
Largest isolated single cell is _________
egg of an ostrich
40
Size of typical eukaryotic cell?
10-20 micrometers
41
Size of viruses?
0.02-0.2 micrometer
42
Size and full-form of PPLO?
0.1 micrometer
| Pleuro Pneumonia Like Organisms
43
Human RBCs are about 7.0 µm in radius. T or F?
False, in diameter
44
_______ cells are some of the longest cells in multicellular organisms
Nerve
45
Match the following:
1. round and biconcave
2. branched and long
3. elongated
4. round and oval
5. long and narrow
6. amoeboid
Columnar epithelial cells, Tracheid, Mesophyll, RBC, WBC, Nerve cells
1. round and biconcave - RBC
2. branched and long - nerve cells
3. elongated - tracheid
4. round and oval - mesophyll
5. long and narrow - columnar
6. amoeboid - WBC
46
____ (____m) and _____ (_____m) units are visible in electron microscope but not in compound microscope
Nanometer 10^-9
| Angstrom 10^-10
47
____ (____m) and _____ (_____m) units are visible in compound microscope
Micrometer 10^-6
| Millimeter 10^-3
48
Some eukaryotic cells measure in millimeters. T or F?
True
49
Shapes of cells vary with the functions they perform. T or F?
True
50
Blue green algae and PPLO are prokaryotic cells. T or F?
True
51
Pick which of these are correct:
Prokaryotic cells are ________ compared to eukaryotic
smaller, have nuclear membrane, multiply rapidly, unique inclusions, no organelles at all
smaller, multiply rapidly, unique inclusions
52
4 basic shapes of bacteria?
Bacillus - rod
Coccus - spherical
Vibrio - comma
Spirillum - spiral
53
Shapes, functions and fundamental organisation of prokaryotic cells vary greatly. T or F?
False,
shapes and functions vary greatly
but fundamental organisation is similar
54
All prokaryotes have a _______ surrounding the cell membrane except _______
cell wall, mycoplasma
55
Genetic material in prokaryotes is held how in the cell?
basically naked, not enveloped
56
Prokaryotes have what all types of DNA?
1. Genomic (single chromosome / circular DNA)
| 2. Plasmid (small circular DNA outside the genomic)
57
Plasmid DNA confers _______ to bacteria such as ________
unique phenotypic characters, antibiotic resistance
58
Plasmid DNA is present in _____________ (all / some / none) bacteria and _____________ (all / some / none) eukaryotes
some, none
59
Bacterial DNA is aka _____________ or _____________
nucleoid, main genomic DNA
60
_____________ in bacteria contains the essential genes whereas _____________ contains non-essential genes
Nucleoid, plasmid
61
Plasmid vs genomic DNA. Similarities (2) and differences (3,2)
Similarities - double-stranded, circular
Differences -
Plasmid is more than one, extrachromosomal and self-replicating independent of nucleoid
Genomic DNA is singular and naked
62
Bacterial surface structures are aka cell membrane extensions. T or F?
False, cell WALL extensions
63
A specialized differentiated form of cell membrane called _________ is found in prokaryotes. They are essentially _____ of cell membrane.
mesosome, infoldings
64
Most prokaryotic cells, particularly bacterial cells, have a chemically simple cell envelope. T or F?
False, complex
65
Cell envelope of prokaryotes consists of tightly bound 3 layered structure. What are the layers?
(outermost) Glycocalyx > Cell wall > Plasma membrane
66
Each layer of prokaryotic cell envelope has distinct features and functions. They do not have any coordinated function. T or F?
False, they have distinct functions but act together as a single protective unit
67
Bacteria can be classified into how many groups on basis of cell envelope differences? What are they? How are they identified?
2 groups,
Gram positive and Gram negative
Gram positive take up the gram stain, negative don't
68
Glycocalyx differs in ______ and _____ among different bacteria
composition and thickness
69
Glycocalyx as a loose sheath is called _____ and as a thick and tough layer is called _______
slime layer;
| capsule
70
Glycocalyx is made up of ___________
mucopolysaccharides (carbohydrates)
71
What are the functions of glycocalyx?
1. protects from host immune system
2. adhesion
3. prevents loss of water and nutrients
4. prevents from dessication
72
What are the functions of the cell wall layer of the cell envelope?
1. Determines the shape of the cell
2. Provides strong structural support
3. Prevents bacterium from bursting or collapsing
73
Cell wall in bacteria is non-cellulosic. T or F?
True
74
Cell wall is made up of _____________ which in turn constitutes (3) things?
peptidoglycan
NAG - N-acetyl glucosamine
NAM - N-acetyl muramic acid
Amino acids / peptides
75
NAM and NAG alternate in cell wall of bacteria and peptide chains form on _________ (NAM / NAG)
NAM
76
What is cross-linking in bacteria?
Peptide bonds in cell wall form cross-links - grid-like structure - makes cell wall stronger
77
Penicillin prevents _____________ in bacteria thereby causing the cell wall to undergo _____________
cross-linking,
| osmotic bursting
78
Why does penicilin not kill mycoplasma?
Because penicillin works by breaking down cell wall and mycoplasma has no cell wall
79
________ layer of prokaryotic cell envelope is selectively permeable and similar structurally to that of eukaryotes
Plasma membrane
80
Composition of cell wall in plants vs bacteria vs fungi?
Plants - cellulose
Bacteria - peptidoglycan
Fungi - chitin
81
Cell wall of plants, fungi and bacteria are made up of the same fundamental substance - carbohydrates. T or F?
True
82
_________ cells do not have cytoskeletal elements (threads on the inside providing structural support)
Bacteria or eukaryotic
Bacteria
83
Lysozyme in _______ and ______ in humans destroys bacteria by __________
saliva, tears, breaking down cell wall
84
Archaebacteria is not made up of peptidoglycan. T or F?
True
85
Gram positive bacteria retain the stain and are ______ in color.
Gram negative bacteria are colorless or ______ stain
blue, pink
86
Gram positive vs Gram negative bacteria
Comment on: cell wall/envelope - thin or thick?
amount of peptidoglycan and lipid?
presence of pili and porins
Gram positive - thick cell wall/envelope, more peptidoglycan but less lipid, no pilli or porins
Gram negative - thin cell wall/envelope, less peptidoglycan but more lipid, pilli and porins present
87
Categorize into Gram positive and Gram negative bacteria:
E Coli, Lactobaccillus, clostridium, mycoplasma, cyanobacteria, Frankia, Rhizobium, Streptococcus, Bacillus
```
E Coli - Negative
Lactobaccillus - Positive
Clostridium - Positive
Mycoplasma - Negative
Cyanobacteria - Negative
Frankia - Positive
Rhizobium - Negative
Streptococcus - Positive
Bacillus - Positive
```
88
Cell membrane is made up of a __________ bilayer
phospholipid
89
Cell membrane layer has a ______ head which is __________ (hydrophobic/hydrophillic) and two arms made up of _____ chains that are __________ (hydrophobic/hydrophillic)
polar, hydrophilic,
| carbon, hydrophobic
90
Phospholipid in cell membrane is made up of _____ fatty acids and one ____________
two, phosphate
91
Mesosome is formed by extensions of cell wall or plasma membrane into the cell. T or F?
False, extensions of plasma membrane only
92
Mesosome plasma membrane extensions can be in what forms? (3)
vesicles
tubules
lamellae
93
What does mesosome help in? (6)
cell wall formation,
DNA replication and distribution to daughter cells,
respiration,
secretion processes,
increase surface area of plasma membrane,
increase enzymatic content
94
Mesosome is similar in function to _____________ in eukaryotes
cristae of mitochondria
95
What is a unique feature of the cyanobacteria cell envelope?
Chromatophores, membranous extensions into the cytoplasm containing pigments
96
Chromatophores are analogous to _____________ in eukaryotes
thylakoid of chloroplasts
97
Bacterial cells are always motile. T or F?
False, can be motile or non
98
Motile bacterial cells have ______ extensions from the cell wall called flagella
filamentous
99
Non-motile bacteria do not show movement. T or F?
False, they move passively (e.g. carried by water)
100
All bacteria have the same or similar flagella number and arrangement. T or F?
False, diverse
101
What are the 3 parts of a bacterial flagellum?
1. Filament
2. Hook
3. Basal body
102
_________ is the longest portion of the bacterial flagellum. It extends from where to where?
Filament,
| from cell surface to outside
103
Flagella of bacteria is made of single thread of _____________
flagellan protein
104
Filament is the largest surface structure in bacteria. T or F?
False, flagella
105
Bacterial and eukaroytic flagella differ in their roles and structural make-up. T or F?
False, differ in structural make-up but SAME role of movement
106
Bacterial flagella vs eukaryotic flagella? (2)
| protein and arrangement
bacteria - flagellan protein, NO 9+2 arrangement
| eukaryote - tubulin protein, 9+2 arrangement
107
What are the 6 types of flagella arrangement?
Monotrichous, Amphitrichous, Peritrichous, Cephalotrichous, Atrichous
108
Peritrichous has flagella _____________ for example _____________
in all directions, E. Coli
109
Cephalotrichous has flagella _____________ whereas lophotrichous has flagella _____________ (example: _____________)
on head, two ends (spirillium)
110
Atrichous bacteria are _____________ (with/without) flagella and _____________ (motile/non-motile)
Examples? (3)
without, non-motile
cyanobacteria, mycoplasma, coccus
111
Flagella, Pili and Fimbriae are 3 surface structures that play a role in bacterial motility. T or F?
False, 3 surface structures but latter 2 don't play role in motility
112
Pilli are _________ and ________ surface structures made up of a special protein called _______
elongated, tubular, pillin
113
Fimbriae are _____________, ________-like fibres sprouting out of the bacterial cell
small, bristle-like
114
Role of pilli vs fimbrae
Pilli - sexual reproduction / conjugation
| Fimbrae - attach to substratum (host or rock)
115
Fimbrae are less in number compared to pilli which are many in number. T or F?
False, other way around
116
Eukaryotic cells are usually measured in micrometers and some in millimeters. T or F?
True
117
Prokaryotic cells are usually measured in _________meters
micro
118
Size of ribosomes (in nm) in prokaryotic cells?
15 nm by 20 nm
119
What are the two subunits of ribosomes? Together they form?
50S and 30S, together form 70S prokaryotic ribosomes
120
50S is the smaller unit of ribosome whereas 30S is the larger unit. T or F?
False, reverse
121
Ribosomes are the site of ________
protein synthesis
122
Ribosomes are _____________ (membrane-bound or non-membrane bound)
non-membrane bound
123
What is a polysome? aka?
Several ribosomes attach to a single mRNA and form a chain, aka polyribosomes
124
Ribosomes translate mRNA into _____________ and once folded they become proteins
polypeptides
125
First ___S ribosomal subunit attaches to mRNA followed by ___S
30S, 50S
126
Inclusion bodies are soluble small-size organelles that are granular in appearance. T or F?
False, insoluble
| Rest is correct
127
Why are inclusion bodies insoluble?
So that they take less space in cytoplasm
128
What are inclusion bodies?
reserve material in stored in prokaryotic cytoplasm
129
Inclusion bodies are not bound by any membrane and lie free in prokaryotic cytoplasm. T or F?
True
130
Examples of inclusion bodies?
Glycogen granules, phosphate granules, cyanophycean granules, glycogen granules
131
________ (type of inclusion body) are found in blue green and purple and green photosynthetic bacteria
Gas vacuoles
132
_____________ are aka pseudovacuoles. Why?
Gas vacuoles, they have a membrane (whereas other vacuoles don't) but the membrane is NOT made up of lipid
133
Gas vacuoles are a type of _____________ (name of the organelle)
inclusion body
134
Gas. vacuoles are found in plant cells. T or F?
False, cyanobacteria
135
Rank in order of solubility?
Starch, glycogen, glucose
Glucose - most soluble
Starch - less
Glycogen - least
136
Eukaryotes include:
protists
plants
animals
fungi
137
Four types of plasmid?
Resistance "R"
Tumor inducing "Ti"
Fertility "F"
Degenerative
138
What does R plasmid do?
Confer antibiotic resistance
139
_____________ plasmid results in uncontrolled cell growth in roots of plants
Ti
140
Ti plasmid is present in __________ organism
Agrobacterium tumifacien
141
______________ is aka natural genetic engineer
Agrobacterium Tumifacien
142
What is the role of F plasmid?
transfer of plasmid from one bacteria to another (primitive method of sexual reproduction i.e. conjugation)
143
In conjugation, _____________ bacteria has pilli whereas _____________ does not
F+ (male)
| F- (female)
144
What is unique about degenerative plasmid? Example of bacteria that contains it
Digests oil spills - bioremediation
| e.g. Pseudomonas putida
145
There is extensive compartmentalization of cytoplasm in eukaryotes. T or F?
True
146
Eukaryotes have a variety of complex locomotory and cytoskeletal structures. T or F?
True
147
Genetic material in eukaryotic cells is organised into ___________
chromosomes
148
All eukaryotic cells are identical. T or F?
False
149
Organelles without membrane vs. double membrane vs. single membrane
without membrane:
1. nucleolus
2. centriole
3. ribosome
double membrane:
1. mitochondria
2. chloroplast
3. nucleus
single membrane:
1. ER
2. Golgi bodies
3. lysosome
4. vesicles
5. vacuole
6. peroxisome
7. cilia/flagells
150
Plant vs. animal eukaryotic cells?
Plant - cell walls, plastids/chloroplasts and large central vacuole
Animals - none of the above + have centrioles
151
Cell membrane is present in all cells. T or F?
False, all LIVING cells
152
Cell membranes are absent in _____________, _____________ and _____________
tracheids, vessels, fibres
| dead cells
153
Why did we chemically study cell membrane of RBC?
Because RBCs do not contain organelles that could be confused for cell membrane (no golgi, ER, mitochondria or nucleus)
154
Detailed structure of the cell membrane was only studied after the advent of ______ in the _____
electron microscope, 1950s
155
Phospholipids are _____________ i.e. they have non-polar and polar parts
amphipathic
156
Chemical studies on cell membrane (before advent of electron microscope) enabled scientists to deduce ________
possible structure of the plasma membrane,
| cell membrane is mainly composed of lipids and proteins, also contains carbohydrates
157
Chemical studies to study cell membrane before the advent of the electron microscope were conducted on which cells?
Human RBCs
158
Major lipids are _________ arranged in a ______ in cell membrane
phorpholipids, bilayer
159
Lipids in cell membrane have ________ oriented towards the outer side and _________ oriented towards the inner part
polar head,
| hydrophobic tails
160
What does the orientation of lipid head and tail ensure?
Nonpolar tail of saturated hydrocarbons is protected from aquaeous environment
161
Cell membrane contains cholesterol. T or F?
True
162
Ratio of protein to lipid is consistent across different cell types. T or F?
False, varies
163
Protein-lipid ration in human RBCs?
52% (protein) to 40% (lipid)
164
Depending on __________ membrane proteins can be classified as integral and peripheral.
Ease of extraction
165
Peripheral proteins lie _____ while integral proteins lie ________
peripheral - on surface of membrane
| integral - partially or totally buried in membrane
166
In mitochondria, F1 complex is an example of a _____________ protein whereas F0 complex is an example of a _____________ protein
peripheral, integral
167
_____________ proteins are more common in plasma membrane (integral vs peripheral)
Peripheral
168
Cholesterol provides _____________ to cell membrane
stability
169
Cholesterol is present in _____________ and _____________ cells and absent in _____________
animal cells, mycoplasma
| absent: plant
170
_____________ (specifically _____________) on cell membrane act as antigens
Glycoproteins, sugar chains
171
What is Singer and Nicolson's model of cell membrane? When was it proposed?
1972, fluid mosaic model,
| quasi-fluid nature of lipid enables lateral movement of proteins within the overall bilayer
172
_____________ is the measure for fluidity within the membrane
ability to move within the membrane (greater lateral movt => more fluid)
173
6 functions that fluid nature of plasma membrane helps in?
1. Cell division
2. Cell growth
3. Endocytosis (phagocytosis-eating + pinocytosis-drinking)
4. Exocytosis (cell vomiting)
5. Making intercellular junctions
6. Transport of molecules (active and passive)
174
Why can't dead cells undergo plasmolysis?
Because they do not have a cell membrane
175
One of the most important functions of the cell membrane is __________
transport of molecules across it
176
According to the Singer and Nicolson model, proteins are like _____________ and phospholipids are like the a _____________
icebergs, sea
177
Proteins only exhibit lateral movement within cell membrane, whereas lipids can move: (3)
laterally, flip flop or rotational
178
Plasma membrane contains ______-______% proteins and ______-______% lipids
20-70% proteins
| 20-80% lipids
179
Other than proteins and lipids, cell membrane contains carbohydrates, enzymes and water. T or F?
True
180
Cell membrane is selectively permeable to some molecules on either sides. T or F?
True
181
Passive vs. Active transport
Passive - no energy required, along gradient (high to low), simple diffusion
Active - ATP utilised, against gradient (low to high)
182
Bulk vs specific transport
Bulk - large molecules
| Specific - individual / smaller molecules
183
Endocytosis vs exocytosis
Endo - substance enters cell (phago or pino)
| Exo - substance leaves cell (secretion or excretion)
184
How do each of these move across cell membrane?
Gas
H2O
Neutral/non-polar solutes (give example)
Polar solutes (give examples)
Gas - diffusion
H2O - osmosis
Neutral solutes - diffusion e.g. lipids, steroids
Polar solutes - channels or pumps (e.g. Na+, Cl-, Glucose, Fructose)
185
__________ (polar / non-polar) solutes are water soluble
Polar
186
_______ molecules cannot pass through the lipid bilayer and they require a _______ to facilitate their transport
Polar, carrier protein
187
Pump vs. channel (4)
Pump - made up of protein, requires ATP, active transport from low to high
Channel - made up of protein, no E required, passive transport from high to low
188
Cell membrane is a living structure whereas cell wall is a non-living structure. T or F?
True
189
Cell wall is a non-living rigid structure of fungi and plants. T or F?
True
190
Cell wall functions?
```
shape to cell
protects from mechanical damage
protects from infection
helps in cell-to-cell interaction
barrier to undesirable macromolecules
prevents osmotic bursting
```
191
Algae have cell wall made of _______
cellulose,
galactans,
mannans,
minerals (calcium carbonate)
192
Plants (except algae) have cell wall made of?
cellulose,
hemicellulose,
pectins,
proteins
193
Cell wall of young plant cell is called ___________
primary wall, growth
194
____________ (primary / secondary) cell wall is capable of growth and ____________ (innermost / outermost)
Primary, outermost
195
Primary wall gradually diminishes as cell matures and gives way to ______ formed on the _____ side of the cell
secondary wall, inner (towards membrane)
196
Secondary cell wall lies between ____________ and ____________
primary cell wall, plasma membrane
197
Secondary cell wall is made up of ____________
cellulose
| deposits of pectin / suberin / lignin
198
_____ is a layer of cell wall mainly made of calcium pectate which has ______ function
middle lamella, flues the different neighbouring cells together
199
Middle lamella is present in almost all cells of plants except ____________
epidermal cells
200
When fruits ripen and go soft, it is due to the degeneration of this part ____________
middle lamella
201
Cell wall and middle lamellae may be traversed by _________ which connect _______ of neighbouring cells
plasmodesmata, cytoplasm
202
Plasmodesmata are present in maximum number in ____________ cells
dividing / meristematic
203
Many membranous organelles of cell together considered _______ system because of ________
endomembrane system, coordinated functions
204
Endomembrane system includes? (4)
ER - endoplasmic reticulum
Golgi complex
Lysosomes
Vacuoles
205
Functions of ________, ________ and _______ are NOT coordinated with endomembrane sys?
mitochondria,
chloroplast,
peroxisomes
206
Electron microscope studies of eukaryotic cells finally revealed presence of:
lipids, proteins, ER
ER
207
ER is a network or _________ of tiny _________ structures scattered in cytoplasm
reticulum, tubular
208
ER divides the intracellular space into how many compartments? What are they?
2,
luminal (inside ER)
extra-luminal (cytoplasm)
209
ER often shows ______ attached to their outer surface
Ribosomes
210
RER vs. SER? (2)
RER - with ribosomes, protein synthesis
SER - without ribosomes, lipid/fat synthesis
211
RER is site for ___________
| SER is major site for __________
protein synthesis and secretion,
| lipid synthesis
212
SER is extensive and continuous with the outer membrane of the nucleus. T or F?
False, RER
213
In plant and animal cells, lipid-like steroidal hormones are synthesized in SER. T or F?
False,
| in animal cells only - rest is accurate
214
____________ subunit of ribosome attaches to the RER
60S, larger
215
Polypeptide produced by mRNA and ribosome goes into ____________ to be folded into a protein
lumen of ER
216
When considering the biogenesis, which came first: RER or SER?
RER, then evolved into SER
217
Apart from synthesis of lipid and steroids, SER is also responsible for ____________ and ____________
detoxification
| storing Ca in muscle cells
218
What are the 3 structures/shapes in ER?
Cisternae, tubules, vesicles
219
Match the structure to the function:
1. cisternae
2. tubules
3. vesicles
lipid and sterol synthesis, protein synthesis, packing and transport
1. cisternae - protein synthesis
2. tubules - lipid and sterol synthesis
3. vesicles - packing and transport
220
_________ first observed densely stained reticular structures near the nucleus. What year?
Camillo Golgi (1898)
221
Golgi bodies consist of many flat, disc-shaped sacs or cisternae stacked perpendicular to each other. T or F?
False, stacked parallel rest is correct
222
Golgi body sacs diameter: ______
0.5 μm to 1.0 μm
223
_____________ are unicisternal whereas _____________ are multicisternal
plants, animals
224
A fixed standard number of cisternae are present in Golgi complex. T or F?
False, varied
225
What are 'cis' and 'trans' faces of Golgi?
convex / forming face - cis
| concave / maturing face - trans
226
Golgi complex cisternae are _________ arranged near the nucleus
concentrically
227
Cis and trans faces of the golgi complex are entirely different but interconnected. T or F?
True
228
Function of golgi apparatus? (4)
Modification
Packaging and sorting materials to be delivered intra-cellularly or outside the cell
Formation of glycoproteins and glycolipids
Formation of lysosome
229
Materials to be packaged by golgi are in form of ______ from the ER fuse with ____ face of the apparatus and move towards the _____ face
vesicles, cis, trans
230
Why does the golgi apparatus remain in close association with ER?
to transfer vesicles from ER
231
Proteins synthesized by ribosomes on ER are modified in the _________ of golgi before release
cisternae
232
Golgi apparatus is important site of formation of ____ and ____
glycoproteins
| glycolipids
233
Lysosomes are membrane found ______ structures formed by process of _______
vesicular, packaging
234
Lysosomal vesicles are rich in _______
almost all types of hydrolytic enzymes active at acidic pH:
| hydrolases, lipases, proteases, carbohydrases
235
Enzymes found in lysosomes are capable of digesting ___________
macromolecules:
| carbs, proteins, lipids and nucleic acids
236
________ is a membrane-bound space found in the cytoplasm
Vacuoles
237
Vacuoles contain:
water, sap, excretory product and other materials not useful for the cell
238
Vacuole is bound by a single membrane called _________
tonoplast
239
In plant cells, vacuoles can occupy up to _____% of cell volume
90%
240
What is role of tonoplast in plants?
Facilitates transport of number of ions/other materials against gradient into the vacuole
241
Why is concentration of ions / other materials higher in vacuole?
Tonoplast transports them against gradient
242
In Amoeba _______ vacuole is important for osmoregulation
contractile
243
In cells like protists ______ vacuoles are formed by engulfing food particles
food
244
Mitochondria are easily visible under the microscope. T or F?
False, only if specifically stained
245
Number of mitochondria, shape and size per cell is fixed. T or F?
False, considerable degree of variability depending on the physiological activity of the cells
246
Shape and size of mitochondrion?
Sausage-shaped / cylindrical,
diameter of 0.2-1.0 μm (average 0.5 μm)
length 1.0-4.1 μm
247
There is an inter-membrane space between the outer and inner membrane of mitochondrion. T or F?
True
248
Each mitochondrion is a double membrane-bound structure with the outer and inner membrane dividing its lumen into two aqueous compartments. T or F?
True
249
Inner compartment of mitochondrion is filled with _______, a dense homogenous substance.
Matrix
250
_________ membrane forms the continuous limiting boundary of the organelle.
Outer / inner / both
Outer
251
Inner membrane of mitochondria has a number of folding called __________.
These are towards / away (?) from the matrix.
crista, towards
252
What do the crista do?
Increase surface area
253
The two membranes of mitochondrion share a common set of enzymes produced by the power houses of the cell. T or F?
False, own specific enzymes
254
Mitochondria are the site of anaerobic or aerobic respiration?
aerobic
255
They produce energy in the form of _____, hence they are called ________ of the cell
ATP, 'power houses'
256
Matrix of mitochondria possesses ?
- single circular DNA molecule
- few RNA molecules
- ribosomes (70S)
- components required for protein synthesis
257
Which ribosomes would you find in mitochondria?
70S
258
Mitochondria divide by _________
fission
259
Plastids are found in ________
all plant cells and in euglenoides
260
Plastids are small but are easily observed under the microscope. T or F?
False, they are large
261
Plastids bear specific pigments, thus imparting color to the plants. T or F?
True
262
Plastids can be classified into 3 based on ________
What are the 3 types?
based on type of pigment
chloroplasts, chromoplasts and leucoplasts
263
Which pigments do each of the plastid types contain?
Chloroplasts - chlorophyll (green color) and carotenoid
Chromoplasts - carotenoid - carotene, xanthophyll, etc. (yellow / orange / red color)
Leucoplasts - colorless
264
Carotenoid is present in both chloroplasts and chromoplasts. T or F?
True
265
What are functions of chloroplasts and leucoplasts?
Chloroplasts - trap light energy for photosynthesis
| Leucoplasts - store nutrients
266
Types of leucoplasts and what they store?
amyloplasts - carbs (starch),
elaioplasts - oils and fats,
aleuroplasts - proteins
267
Majority of chloroplasts are found in ______ cells of the leaves
mesophyll
268
Shapes of chloroplasts?
```
Lens-shaped
Oval
Spherical
Discoid
Ribbon-like
```
269
Length and width of chloroplasts?
length: 5-10 µm
width: 2-4 µm
270
How many chloroplasts in Chlamydomonas?
1 per cell
271
How many chloroplasts in green alga?
20-40 per cell
272
Chloroplasts and mitochondria are both double-membraned organelles, however, inner membrane of mitochondria is relatively less permeable. T or F?
False, first part is correct, but inner membrane of chloroplast is relatively less permeable
273
Space limited by the inner membrane of the chloroplast is called _______
stroma
274
A number of organised flattened membranous sacs called ______ are present in stroma
Thylakoid
275
What is special about thylakoid arrangement?
- in stacks called "grana" (like piles of coins)
| - flat membranous tubules called stroma lamellae connecting thylakoid of different grana
276
Another name for thylakoids arranged in grana?
intergranal thylakoids
277
________ of the thylakoids enclose a space called ________
membrane, lumen
278
Stroma of chloroplasts contains ?
- Intergranal thylakoids
- enzymes for carb and protein synthesis
- small, double stranded circular DNA molecules
- ribosomes
279
_________ pigments are present in the thylakoids
Chlorophyll
280
Ribosomes of chloroplasts are 80S or 70S?
Ribosomes of the cytoplasm?
Which are smaller?
chloroplasts - 70S, smaller
| cytoplasm - 80S
281
Ribosome were first observed under the electron microscope as ________ by __________ in the year __________
dense particles,
George Palade
1953
282
Ribosomes are ___________ structures, composed of ________ and _______.
granular, RNA and proteins
283
Mitochondria, ribosomes and chloroplasts are double-membraned structures. T or false?
False, ribosome has NO membrane
284
Eukaryotic ribosomes are ____S and prokaryotic are ____S
eukaryotic - 80S
| prokaryotic - 70S
285
What are the subunits of 70S? 80S?
70S: 50S and 30S
80S: 60S and 40S
286
What does S (wrt ribosomes) stand for?
Svedberg's Unit, sedimentation coefficient, indirect measure of density and size
287
What are cytoskeleton?
- elaborate network of filamentous proteinaceous structures
- consist of microtubules, microfilaments and intermediate filaments
- present in cytoplasm
288
What functions are cytoskeleton involved in?
- mechanical support
- motility
- maintenance of cell shape
289
______ and ______ are hair-like outgrowths of the cell membrane
cilia and flagella
290
Cilia vs. flagella structure?
cilia - small, work-like oars
| flagella - longer
291
Cilia cause movement of ________ where flagella are responsible for ______ movement
cilia - cell or surrounding fluid
| flagella - cell
292
Prokaryotic bacteria flagella are structurally similar to eukaryotic flagella. T or F?
False, structurally different
293
Cilia and flagella are covered with __________ and have a core called _______
plasma membrane
| core - axoneme
294
Axoneme of cilia/flagella possesses a number of ________ running parallel to _______
microtubules, long axis
295
Axoneme has ____ doublets of radially arranged peripheral microtubules and a pair of _______ located microtubules.
This arrangement is called ________
nine, centrally
9+2 array
296
Central tubules of axoneme are connected via _______ whereas peripheral doublets are interconnected by ______
bridges, linkers
297
Central tubules are enclosed by a ________
central sheath
298
Central sheath of central tubules is connected to ___________ by radial spoke
one of the tubules of each peripheral doublet
299
How many radial spokes in an axoneme?
9 (since 9 doublets)
300
Cilium and flagellum emerge from ________-like structure called basal bodies
centriole-like
301
__________ is an organelle usually containing 2 cylindrical structures called _______
Centrosome, centrioles
302
Centrioles like ______ to each other and each has an organisation like ________
perpendicular, cartwheel
303
Centrioles are surrounded by ___________
amorphous pericentriolar materials
304
Centrioles are made up of nine evenly spaced peripheral fibrils of ________. Each fibril is a ______, with adjacent ones linked.
tubular protein, triplet
305
The ______ part of the ______ region of the centriole is also proteinaceous and called the hub. It is connected with peripheral fibril triplets by radial spokes made of _______
central, proximal, protein
306
Centrioles form the basal body of ______ or _______
cilia or flagella
307
Centrioles form the basal body of _____ that give rise to spindle apparatus during cell division
spindle fibres
308
Spindle fibers give rise to the spindle apparatus during cell division in plant and animal cells. T or F?
False, in animal cells
309
Nucleus was first described by Robert Brown, but it was stained by basic dyes and given the name _________ by ________
chromatin, Flemming
310
Interphase nucleus is the nucleus when it is _________
not dividing
311
Interphase nucleus has highly extended and elaborate _____________ called chromatin, ______ matrix and one or more spherical bodies called _______
nucleoprotein fibres, nuclear, nucleoli
312
Nuclear envelope forms a barrier between _______ and ______
materials inside the nucleus and cytoplasm
313
Nuclear envelope consists of ________ membranes with a space between called _________
parallel, perinuclear space
314
Size of perinuclear space is ________
10 to 50 nm
315
Outer membrane of nucleus usually remains continuous with ________ and also bears ________
ER, ribosomes
316
The nuclear envelope is interrupted at a number of places by _______ formed by the fusion of ________
minute pores, fusion of its two membranes
317
Nuclear pores are the passages through which movement of _______ takes place in ____ direction(s) between nucleus and cytoplasm
RNA and proteins, both directions
318
Some mature cells lack nucleus like erythrocytes of mammals and sieve tube cells of plants. T or F?
True
319
Nuclear matrix is aka ________
nucleoplasm
320
Nucleoplsam contains ____ and _____
nucleoli (special structures) and chromatin
321
Content of nucleolus is discontinuous with rest of nucleoplasm because it has a membrane separating the contents of nucleolus from matrix. T or F?
False, continuous and no membrane
322
Nucleolus is a site for __________ synthesis
active ribosomal RNA synthesis
323
__________ are present in cells actively carrying out protein synthesis
Larger and more numerous nucleoli
324
During different stages of cell divisions, cells show structured ___________ instead of nucleus
chromosomes
325
What do chromatin contain?
DNA,
basic proteins called histones
non-histone proteins
and also RNA
326
A single human cell has approximately ____ meter long thread of DNA among its _______ chromosoms
2m, 46 chromosomes
327
Chromosomes are visible only in dividing cells. T or F?
True
328
What are centromere and kinetochores?
centromere - primary constriction in chromosome
| kinetochores - disc-shaped structures on sides of centromere
329
__________ holds two chromatids of chromosomes.
Kinetochore or centromere?
Centromere
330
Chromosomes can be classified into 4 types based on ________. They are?
position of centromere;
metacentric - two equal arms
sub-metacentric - slightly away from middle (one shorter, one longer)
acrocentric - close to its end (one extremely short and one very long)
telocentric - terminal
331
Sometimes a few chromosomes have non-staining secondary constrictions at a constant location, giving the appearance of a fragment called ________
satellite
332
_______ are membrane-bound minute vesicles that contain various enzymes
Microbodies
333
Microbodies are present only in animal cells. T or F?
False, plant and animal
334
Typical eukaryotic cell consists of cell membrane, nucleus and cytoplasm. T or F?
True
335
Nucleus controls activity of organelles and plays major role in ________
heredity
336
ER helps in transport of substances and synthesis of _______
proteins, lipoproteins and glycogen
337
Mitochondria help in ___________ and generation of _______
oxidative phosphorylation and generation of adenosine triphosphate (ATP)
