GEN BIO CELLS Flashcards
1
Q
The discovery of cells is generally credited to ________ for coining the term cellulae that was shortened to cell
A
Robert Hooke
2
Q
What he actually observed were the empty cell walls of dead plant tissue, walls that had originally been produced by the living cells they surrounded.
A
Robert Hooke
3
Q
first to examine a drop of pond water and scrapings from his teeth under the microscope and observed the teeming microscopic “animalcules”.
A
ANTON VAN LEEUWENHOEK
4
Q
Botanist who concluded that all plants are made of cells
A
Matthias Schleiden
5
Q
Stated that all animals are made of cells
A
Theodor Schwann
6
Q
Proposed that animal and plant cells are produced only by the division of cells that already exist
A
Rudolf Virchow
7
Q
unifying foundation of cell biology
A
Cell Theory
1. All organisms are composed of one or more cells.
2. The cell is the structural unit of life.
- cells are the basic units of organization of all organisms
3. Cells can arise only by division from a preexisting cell.
8
Q
Common Components of all Cells (Components that are found in every cell)
A
- CEntrally located genetic material
- Cytoplasm
- Plasma Membrane
- Ribosomes
9
Q
consists of a jelly-like cytosol within the cell in which other cellular components are found
A
Cytoplasm
10
Q
Centrally located genetic material can be _______ in prokaryotic cells and ___________ in eukaryotic cells
A
nucleoid; nucleus
11
Q
an outer covering that separated the cell’s interior from its surrounding environment
A
Plasma Membrane
12
Q
synthesize proteins
A
Ribosomes
13
Q
pro= “ “ and karyon= “ “
A
pro- = “before” ; -karyon- =“nucleus”
14
Q
_Procaryotic cells are predominantly single-celled (unicellular) organisms of the domains ________ and ________
A
Bacteria and Archaea
15
Q
-these cells have no membrane-bound organelles such as the nucleus
A
Prokaryotic
16
Q
- Eukaryotic (eu- = “ ”)
A
True
17
Q
cells of animals, plants, fungi, and protists. With membrane-bound organelles and genetic material enclosed in the nucleus
A
Eukaryotic
18
Q
the entire region of a cell within the plasma membrane
A
Cytoplasm
19
Q
In eukaryotes, it is made up of organelles suspended in the gel-like cytosol, the cytoskeleton, and various chemicals
A
Cytoplasm
20
Q
- consists of 70% to 80% water; has a semi-solid consistency due to the proteins within it
- contains all of the sugars, amino acids, and proteins the cell uses to carry out its everyday activities
A
Cytoplasm
21
Q
Encloses a cell and separates its contents from its surroundings
A
Plasma membrane
22
Q
a phospholipid bilayer that controls the passage of organic molecules, ions, water, and oxygen into and out of the cell
A
Plasma Membrane
23
Q
wastes (such as carbon dioxide and ammonia) also leave the cell by passing through the _________
A
plasma membrane
24
Q
induce changes w/in the cell when they come in contact with specific molecules in the environment, such as hormones, or with molecules (markers) on the surface of neighboring cells
A
receptor proteins
25
Eukaryotic and Prokaryotic (these terms refer to the presence or absence, respectively, of a membrane-bounded nucleus that contains genetic material)
distinguished by: their ____________________
sizes, types of internal structures, or organelles
26
(type of cell) DNA is found in the nucleoid region
Prokaryotes
27
(type of cell) DNA is within a membrane-bound nucleus
Eukaryotes
28
(type of cell) usually smaller
Prokaryotes
29
(type of cell) usually bigger
Eukaryotes
30
(type of cell) usually single-celled
Prokaryotes
31
(type of cell) often multicellular
Eukaryotes
32
(type of cell) may not need oxygen in metabolizing nutrients
Prokaryotes
33
(type of cell) usually need oxygen to exist
Eukaryotes
34
(type of cell) no membrane-bound organelles
Prokaryotes
35
(type of cell) membrane-bound organelles
Eukaryotes
36
simplest organisms. __________ cells are small.
Prokaryotes; prokaryotic
37
consist of cytoplasm surrounded by a plasma membrane and are encased w/in a rigid cell wall (acts as an extra layer of protection, helps maintain its shape, and prevents dehydration.) and is composed of peptidoglycans
Prokaryotes
38
carbohydrate matrix that is cross-linked by short polypeptide units
peptidoglycans
39
They have no distinct interior compartments.
Prokaryotes
40
has 2 layers; bacterial cell wall
Gram-Positive bacterial cell wall (Plasma membrane and peptidoglycan cell wall.
41
has 3 layers; bacterial cell wall
Gram-Negative bacterial cell wall (Outer lipid membrane, peptidoglycan, plasma membrane)
42
Aside from prokaryotes, what else has a cell wall
plants, fungi, protists, yeasts
43
Archaea lack a bacterial cell wall layer called _________
peptidoglycan
44
enables the cell to attach to surfaces in its environment
Polysaccharide capsule
45
long, threadlike structures used for locomotion
FLAGELLA
46
used by bacteria to attach to a host cell
FIMBRIAE
47
nerve cells in a giraffe's spinal cord can be how many meters long
2
48
most cells are only about _______ the size of a period at the end of a sentence
1/500
49
most bacterias are only ______ microns
1-10
50
most eukaryotic cells are only ____ microns
10-100
51
1 micron is = __________M
1/1,000,000 m
52
as cell increases in size, its ________ increases faster than its surface area
volume
53
T or F. If the cell grows too large, the plasma membrane will not have the sufficient surface area to support the rate of diffusion required for the increased volume. as a cell grows, it becomes less efficient
T
54
What are the 2 ways for cell to become more efficient
- to divide
- develop organelles that perform specific tasks
55
The Hallmark of the eukaryotic cell is ______________
compartmentalization.
56
achieved through a combination of an extensive endomembrane system that weaves through the cell interior and by numerous organelles (include membrane-bounded structures that form compartments w/in which multiple biochemical processes can proceed simultaneously and independently).
compartmentalization
57
4 basic functional groups of eukaryotic cells
- Manufacturing
- Breakdown or hydrolysis of molecules
- Energy processing
- Structural support, movement, and communication
58
nucleus, ribosomes, ER, and Golgi Apparatus belong to the group _________
Manufacturing
59
lysosomes, vacuoles, and peroxisomes belong to the _________ group
breakdown/hydrolysis of molecules
60
mitochondria and chloroplasts belong to the _______ group
energy processing
61
cytoskeleton, plasma membrane, and cell wall belong to the ________ group
structural support, movement, and communication
62
Almost all of the organelles and other structures present in an animal cell are also present in a plant cell What are the Exceptions?
- Lysosomes and centrioles (not in plants)
- some animal cells have flagella/cilia
- , only the sperm cells of a few plant species have flagella.
- plant cell has cell wall
63
___________ protect cells and help maintain their shape.
Cell walls
64
Difference between plant cell wall and prokaryotic cell wall
- Chemically different from prokaryotic cell walls, plant cell walls contain the polysaccharide cellulose.
65
channels through cell walls that connect adjacent cells.
Plasmodesma/Plasmodesmata
66
An important organelle found in plant cells is the _____________ where photosynthesis occurs
chloroplast,
67
Unique to plant cells is a _____________, a compartment that stores water and a variety of chemicals.
large central vacuole
68
Eukaryotic cells contain nonmembranous structures as well. What are these?
- cytoskeleton
- ribosomes
69
consists of protein tubes called microtubules and other protein filaments
cytoskeleton
70
the cell’s genetic control center and the most prominent organelle in a cell.
Nucleus
71
contains most of the cell’s DNA and controls the cell’s activities by directing protein synthesis.
Nucleus
72
Eukaryotic chromosomes are made up of a material called ______, which is a complex of proteins and DNA.
chromatin
73
Chromosomes are only visible and distinguishable from each other when the cell is getting ready to __________
divide.
74
Enclosing the nucleus is a _____________, a double-membrane perforated with protein-lined pores that control the flow of materials (ions, molecules, and RNA) into and out of the nucleus.
nuclear envelope
75
the semi-solid fluid inside the nucleus, where we find the chromatin and nucleolus
nucleoplasm
76
a prominent structure in the nucleus, is the site where a special type of RNA called ribosomal RNA (rRNA) is synthesized according to instructions in the DNA
nucleolus
77
Proteins enter through the __________ from the cytoplasm are assembled with this RNA to form the subunits of ribosomes.
nuclear pores
78
make proteins for use in the cell and export
RIBOSOMES
79
cellular components that carry out protein synthesis.
Ribosomes
80
Cells that have high rates of protein synthesis have a large number of _______
ribosomes
81
Cells active in protein synthesis also have prominent __________
nucleoli
82
____________ can be thought of as “universal organelles” because they are found in all cell types from all three domains of life
Ribosomes
83
3 domains of life
Bacteria, Archaea, Eukarya
84
Ribosomes are found in two locations in the cell:
- fluid in the cytoplasm (Free rib)
- attached to the outside of ER/nuclear envelope (Bound rib)
85
Most of the proteins made on free ribosomes function within the _________
cytoplasm/cell
86
__________ ribosomes make proteins that will be inserted into membranes, packaged in certain organelles, or exported from the cell.
Bound
87
a ribosome is composed of two subunits
large and small
88
Many cell organelles are connected through the __________ system
endomembrane
89
a system that fills the cell, dividing it into compartments, channeling the passage of molecules through the interior of the cell, and providing surfaces for the synthesis of lipids and some proteins.
endomembrane
90
Some of the membranes are physically connected and some are related by the transfer of membrane segments by _____________(sacs made of membrane).
tiny vesicles
91
The endomembrane system includes the________________ (6)
nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, vacuoles, and the plasma membrane.
92
T or F. The endomembrane system includes the membranes of either mitochondria or chloroplasts.
F. does not include
93
The largest of the internal membranes.
ENDOPLASMIC RETICULUM (ER)
94
Endoplasmic means “_________,” and reticulum is Latin for “_________”
within the cytoplasm; a little net
95
composed more of flattened sacs and forms a compartment throughout the cytoplasm.
Rough Endoplasmic Reticulum
96
Ribosomes transfer their newly synthesized proteins into the lumen of the RER where they undergo structural modifications such as the addition of short-chain carbohydrates to form _________
glycoproteins
97
modified proteins will be incorporated into the cellular membranes-the membrane of the ER or those of other organelles-or secreted from the cell (such as protein hormones, enzymes).
- via
transport vesicles
98
The RER is abundant in cells that secrete _______
proteins
99
the function of the ___________ is to move molecules between different locations inside the cell
transport vesicle
100
membrane-bound sacs that function in storage and transport
vesicles and vacoules
101
T or F. vesicles are larger than vacuoles
F. Vacuoles are larger
102
The membrane of a ________ does not fuse with the membranes of other cellular components.
vacuole
103
__________ also helps the cell grow in size by absorbing water and enlarging, and it can store vital chemicals or waste products in plants
central vacuole
104
a more tubelike structure connected to the RER.
SER
105
Inner region of the ER
SER-cisternal space or lumen
106
Outer region of the ER
cytosol
107
____________ anchored on the SER are involved in the synthesis of a variety of carbohydrates, lipids, and steroid hormones (
Enzymes
108
ovaries and testes are rich in what reticulum
ovaries and testes are rich in SmoothER
109
in the liver, the enzymes of the _______carry out detoxification
SER
110
Storage of calcium ions (in muscle contraction)
SER
111
finishes, sorts, and ships cell products
Golgi Apparatus
112
Golgi apparatus is Named after __________ it consists of flattened sacs stacked on top of each other; the stacks are not interconnected like ER sacs
Camillo Golgi,
113
receives and modifies products manufactured by the ER.
Golgi Apparatus
114
The receiving end of the Golgi apparatus is called the _________ and is usually located near the ER.
cis face
115
Materials arrive at the cis face in transport vesicles that bud off the ER and exit the trans face, where they are discharged in ____________
secretory vesicles
116
The most important alteration when proteins and lipids are transported into the Golgi Apparatus is the addition or modification of short sugar chains, forming _____________
glycoproteins and glycolipids.
117
these can release important molecules in the body
secretory/transport vesicles
118
digestive compartments within a cell
LYSOSOMES
119
Lysosomes is derived from 2 greek words meaning _____________
"breakdown body"
120
Lysosomes arise from
Golgi Apparatus
121
Contain high levels of degrading enzymes, which catalyze the rapid breakdown of proteins, nucleic acids, lipids, and carbohydrates
Lysosomes
122
Break down old organelles and recycle their component molecules
Lysosomes
123
Lysosomes destroy pathogens that might enter the cell
ex. A group of white blood cells called macrophages in a process known as __________________
phagocytosis or endocytosis
124
Contains enzymes involved in the breakdown of fatty acids to be used as fuel and the detoxification of alcohol and other harmful substances
PEROXISOME
125
oxidation reactions in peroxisomes release _________________ which would be damaging to cells; however, when these reactions are confined to peroxisomes, enzymes safely break down the H₂O₂ into oxygen and water
hydrogen peroxide
126
specialized peroxisomes in plants, are responsible for converting stored fats into sugars
* Glyoxysomes
127
Energy-Converting Organelles
- MITOCHONDRIA
- CHLOROPLASTS
128
MITOCHONDRIA harvest chemical energy from _______
food
129
Mitochondria are often called “powerhouses” or “energy factories” of the cell because they are responsible for making ________, the cell’s main energy carrying molecule
ATP
130
Mitochondria carry out _______________ in nearly all eukaryotic cells, converting the chemical energy of foods such as sugars to the chemical energy of ATP
cellular respiration
131
Two internal compartments of a mitochondrion
- Intermembrane Space
- Mitochondrial matrix
132
the narrow region between the inner and outer membranes of a mitochondrion
Intermembrane Space
133
Inner membrane of a mitochondrion encloses the second compartment, the ___________, which contains the mitochondrial DNA and ribosomes, as well as many enzymes that catalyze some of the reactions of cellular respiration
mitochondrial matrix
134
Inner membrane is highly folded (_________);
cristae
135
Inner membrane is highly folded (_________);
cristae
136
foldings inside the mitochondria increases the ________ enhancing capability of ATP production
surface area
137
convert solar energy to chemical energy
Chloroplasts
138
photosynthesizing organelles of all photosynthetic eukaryotes
Chloroplasts
139
The chloroplast is enclosed by an inner and outer membrane separated by a ___________
thin intermembrane space
140
The compartment inside the inner membrane of a chloroplast holds a thick fluid called _______ , which contains the chloroplast DNA and ribosomes as well as many enzymes
stroma
141
a network of interconnected sacs called ___________ is inside the chloroplast
thylakoids
142
compartment inside these sacs (thylakoids) is called the __________
thylakoid space
143
Stack of thylakoids is called _________
granum
144
* A network of protein fibers that help maintain the shape of the cell, secure some organelles in specific positions, allow cytoplasm and vesicles to move within the cell, and enable cells within multicellular organisms move
Cytoskeleton and Cell Surfaces
145
Three types of fibers compose the cytoskeleton
- Microfilaments
- Microtubules
- Intermediate Filaments
146
also called actin filaments
- narrowest; composed mainly of globular proteins called actin, arranged in a twisted double chain
Microfilaments
147
forms a three-dimensional network that helps support the cell’s shape
Microfilaments
148
Microfilaments are also involved in cell movements; filamentous form of actin serves as a track for the movement of a motor protein called__________, cause contraction of muscle cells (actin and myosin are plentiful in muscle cells)
myosin
149
Microfilaments help in Cell division in animal cells and ________________ which is the circular movement of the cytoplasm in plant cells
cytoplasmic streaming
150
can depolymerize (disassemble) and reform quickly, thus enabling a cell to change its shape and move; white blood cells make good use of this ability by moving to the site of infection and phagocytize the pathogen
Microfilament
151
made from various fibrous proteins and have a ropelike structure
Intermediate filaments
152
- no role in cell movement; their role is purely structural, maintaining the shape of the cell, and anchor the nucleus and other organelles in place
- most durable element of the cytoskeleton in animal cells
Intermediate Filaments
153
provides structural stability (part of intermediate filament)
Vimentin
154
found in epithelial cells and structures such as hair and fingernails
keratin
155
intermediate filaments of nerve cells are called ___________
neuro-filaments
156
straight, hollow tubes composed of globular proteins consisting of dimers of α- and β- tubulin subunits
Microtubules
157
in many animal cells, microtubules grow out from a “microtubule-organizing center” called a __________
centrosome
158
within the centrosome is a pair of ____________(barrel-shaped organelles found in the cells of animals and most protists; they occur in pairs, usually at right angles to each other near the nuclear membrane)
centrioles
159
Each centriole is composed of nine triplets of ___________.
microtubules
160
T or F. Centrioles are usually found in plant cells.
F.
161
shape and support the cell and also acts as tracks along which organelles equipped with motor proteins can move.
Microtubules
162
a circle of nine microtubule pairs surrounding two central microtubules (9 + 2 structure)
Eukaryotic cells:
163
made up of strands of the protein actin; often interact with strands of other proteins
microfilaments
164
made up of fibrous proteins organized into tough, ropelike assemblies that stabilize a cells' structure and help maintain its shape
Intermediate Filaments
165
Long, hollow cylinders made up of many molecules of the protein tubulin. Tubulin consists of 2 subunits, a-tubulin and b-tubulin.
Microtubules
166
short cellular projections that are often organized in rows
- are more numerous than flagella on the cell surface
Cilia
167
Specialized Cell Structures
* Centrosome
* Lysosomes
* Chloroplasts
* Central vacuole
* Cell wall
168
In plants and protists, the cell walls are made of ___________, whereas in fungi, the cell walls are composed of ______.
cellulose; chitin
169
In plants:
- ____________ are laid down when the cell is still growing
primary walls
170
between the walls of adjacent cells a sticky substance, called the ____________________, glues the cells together
middle lamella
171
some plants produce strong ________________, which are deposited inside the primary walls of fully expanded cells
secondary walls
172
Instead of cell walls, animals secrete a mixture of glycoproteins into the space around them, forming the _______________
extracellular matrix
173
Fibrous protein __________ (also found in cartilage, tendons, and ligaments) may be abundant in ECM, together with another fibrous protein, ___________; they are embedded in a complex web of other glycoproteins, called ____________, that form a protective layer over the cell surface
collagen; elastin; proteoglycans
174
T or F. Connections between cells, markers of cellular identity, and cell communication involve membrane proteins and proteins secreted by cells.
T
175
___________ (surface markers) give cells identity
Surface proteins
176
most tissue-specific cell-surface markers are _____________, lipids with carbohydrate heads
glycolipids
177
the immune system must recognize “self” and “non-self” in order to defend themselves against invading or malignant cells. They use a particular set of markers, encoded by genes of the __________
MHC proteins (major histocompatibility complex)
178
mechanically attach the cytoskeleton of a cell to the cytoskeletons of other cells or to the extracellular matrix
Adhesive/anchoring junctions
179
cadherin-based junction unique to vertebrates. cadherins interact with intermediate filaments
- join adjacent cells
- support tissues against mechanical stress
* Desmosomes
180
the membranes of neighboring cells are very tightly pressed against each other, knit together by proteins
Tight junctions
181
prevent leakage of extracellular fluid across a layer of epithelial cells.
- lines the digestive tract, preventing the contents from leaking into surrounding tissues
Tight junctions
182
are channels that allow small molecules to flow through protein-lined pores between neighboring cells
communicating junctions
183
these junctions are especially common in animal embryos, where chemical communication between cells is essential for development
communicating junctions
184
communicating junctions are called ______________ in animals; _____________ in plants
gap junctions; plasmodesmata
185
a channel through the cell wall that allows molecules and substances to move back and forth as needed
plasmodesmata
