Eukaryotic Cell: structure and function Flashcards
(188 cards)
1
Q
Facilitated transport can be differentiated from active transport, because active transport requires –
A
an energy source
2
Q
The cell is the basic unit of function and reproduction, because sub cellular components cannot –
A
regenerate whole cells
3
Q
Dialysis is based on a – membrane that mimics the cell membrane and has physical pores of a specified size and resembles the function of the cell membrane
A
semipermeable
4
Q
glucose is a relatively large molecule and cannot freely diffuse through the plasma membrane but requires a – embedded in the membrane
A
transporter protein
5
Q
diabetes results from the inhibited release of – to facilitate the uptake of glucose by the cell
A
insulin
6
Q
T/F: water, small hydrophobic molecules, small ions, and neutral gas molecules can freely diffuse through the semipermeable membrane
A
true
7
Q
A protein that has several regions that contain 20-25 hydrophobic amino acids would most likely be a – protein
A
integral
8
Q
A membrane bound vesicle that contains hydrolytic enzymes is most likely a –
A
lysosome
9
Q
lysosome is the digestive region of the cell and is a membrane bound organelle with a low pH around – that stores hydrolytic enzymes
A
5
10
Q
vacuoles and vesicles are membrane bound sacs involved in the transport and – of materials that are ingested, secreted, processed or digested by cells
A
storage
11
Q
chloroplasts are the site of photosynthesis and are found only in – and plant cell
A
algae
12
Q
vacuoles are – than vesicles and are more likely to be found in plant cells
A
larger
13
Q
chloroplasts contain their own – and – and may have evolved via endosymbiosis in like mitochondria
A
DNA and ribosomes
14
Q
– are vesicles involved in the transport and storages of materials that are ingested by the cell through phagocytosis. The vesicles are formed by the fusion of the cell membrane around the particle
A
phagosomes
15
Q
a phagosome is a cellular compartment in which – can be digested
A
pathogenic microorganisms
16
Q
phagosomes fuse with lysosomes in their maturation process to form –
A
phagolysosomes
17
Q
A DNA damage checkpoint arrests cells in – transition
A
G1/S
18
Q
DNA damage checkpoint is a signal transduction pathway that blocks cell cycle progression in G1, G2, and metaphase and slows down the rate of – progression when DNA is damaged
A
S phase
19
Q
G-C base pairs are linked by – hydrogen bonds
A
3
20
Q
A-T base pairs are linked by – hydrogen bonds
A
2
21
Q
Because of complimentary base-pairing, double-stranded DNA has equal quantities of G = C (and T = A)
A
Chargaff’s rule
22
Q
Phospholipids contain a – backbone, a phosphate group and a simple organic molecule (choline)
A
glycerol
23
Q
phospholipid tails are forced to aggregate via –
A
hydrophobic forces
24
Q
phospholipid hydrophilic heads = glycerol and –
A
negatively charged phosphate group
25
phospholipid hydrophobic tails usually consists of 2 long -- (saturated or unsaturated) hydrocarbon chains
fatty acid
26
-- is embedded within the lipid bilayer in animals but absent in plant cell membranes
cholesterol
27
the overall shape of a cell is determined by its --
cytoskeleton
28
-- is determined by the total concentration of dissolved particles in solution
osmolarity
29
compounds that dissociate into ions increase the concentration of particles and produce a -- osmolarity
increase
30
to determine which molecule (after dissociation into ions) generates the highest osmolarity, determine the number of -- each molecule dissociates into when dissolved in water
individual ions
31
the two ribosomal subunits are produced in the --
nucleolus
32
-- are the site of protein production
ribosomes
33
prokaryotic ribosomes subunits
30S and 50S = 70S
34
eukaryotic ribosomes subunits
40S and 60S = 80S
35
Golgi apparatus ia a membrane-bound organelle that modifies (glycosylation), sorts, and -- proteins
packages
36
rough ER is a portion of the endomembrane system that extends from the --
nuclear envelope
37
rough ER is the site of production and -- of proteins
folding
38
misfolded proteins exit the rough ER and are sent to the -- for degradation
proteosome
39
-- are phosphorylated proteins responsible for specific events during cell division, such as microtubule formation and chromatin remodeling
cyclins
40
cyclins can be divided into four classes based on their behavior in the cell cycle: G1/S, S, -- and G1 cyclins
M
41
p53 is a -- gene
tumor suppressor
42
p53 or guardian of the genome plays a big role in conserving stability by preventing --
genome mutation
43
a codon is a 3-nt segment of an -- that hybridizes (via complementary base pairing) with the appropriate anticodon on the tRNA to encode for one amino acid in a polypeptide chain during protein synthesis
mRNA
44
tRNA only interacts with the mRNA -- the mRNA is bound to the ribosomal complex
after
45
operon regulates the -- of genes into mRNA and is not involved in the translation of mRNA into proteins
transcription
46
peroxisomes are organelles found in most -- cells
eukaryotic
47
peroxisome breaks down very long chain fatty acids through --
beta-oxidation
48
in animal cels, the peroxisome converts the very long fatty acids into medium chain fatty acids, which are subsequently shuttled to the -- where they are eventually broken down via oxidation into CO2 and H2O
mitochondria
49
T/F: RNA can be found in nucleus, mitochondria, prokaryotic cells, and ribosomes
true
50
A vacuole is a membrane-bound organelle which is present in all -- and -- cells and some protist, animal, and bacterial cells
plant and fungal
51
vacuoles are enclosed compartments filled with water and contain inorganic and organic molecules (including enzymes in solution) and may contain -- that have been engulfed
solids
52
the -- and significance of vacuoles varies greatly according to the type of cell with greater prominence in plant cells
function
53
phosphotransferase is needed to form the mannose-6-phosphate tag that targets hydrolase enzymes to their lysosomal destination. Defective phosphotransferase causes I-cell disease. Which defective organelle gives rise to this condition?
Golgi
54
Golgi is part of the endomembrane system and serves as a cellular -- center (packages, processes, modifies)
distribution
55
smooth ER is part of the endomembrane system an dis connected to the nuclear envelope and functions in several -- processes
metabolic
56
smooth ER synthesizes
lipids, phospholipids, steroids
57
cells that secrete lipids, phospholipids, and steroids such as the testes, ovaries, and skin oil glands have an extensive --
smooth ER
58
smooth ER carries out metabolism of -- and --
carbohydrates and steroids
59
smooth ER detoxifies --
drugs
60
smooth ER is responsible for the attachment of -- on cell membrane proteins
receptors
61
mitochondria and chloroplasts are unusual organelles because they contain -- encoded proteins
nuclear and organelle encoded proteins
62
the enzyme cytochrome c oxidase is a large -- complex found in bacteria and mitochondrion of eukaryotes
transmembrane protein
63
-- is the last enzymes in the electron transport chain of mitochondria (or bacteria) located in the mitochondrial (or bacterial) membrane
cytochrome c oxidase
64
cytochrome c oxidase receives an electron from each of four cytochrome c molecules and transfers the electrons to an O2 molecule, converting molecular oxygen to two molecules of --
H2O
65
cytoskeleton is integral in proper cell division because it forms the -- and is responsible for separating sister chromatids during cell division
mitotic spindle
66
cytoskeleton is composed of -- and --
microtubules and microfilaments
67
cytoskeleton gives the cell mechanical support, maintains its shape and functions in cell --
motility
68
mitochondria divide -- to produce daughter mitochondria that incorporate some new nonradioactive and also inherit radioactive from the parent via semi conservation replication
autonomously
69
T/F: post-translational import of proteins involve the Golgi complex
true
70
width of animal cell
20 micrometers
71
ribosomes are composed of specific rRNA molecules and --
associated proteins
72
ribosomes are identified by the -- coefficients (Svedberg units)
sedimentation
73
peroxisomes contain the enzyme -- that decomposed H2O2 into H2O and O2
catalase
74
osmosis is a special type of diffusion involving water and is a form of -- transport
passive
75
high solute and low solvent concentrations
hypertonic
76
low solute and high solvent concentrations
hypotonic
77
solvents always flow spontaneously from an area of --
high solvent to low solvent concentration
78
during osmosis, water flows rom a -- to -- environment
hypotonic to hypertonic
79
after chromosome disjunction, cyclin B is marked for destruction by the --
anaphase promoting complex
80
complex of Cdk and cyclin B is called a maturation or -- promoting factor
mitosis
81
-- is necessary for the progression of the cells into and out of M phase
cyclin B
82
mitochondria have their own DNA genetic material and -- to manufacture their own RNAs and proteins
machinery
83
T/F: all organisms that reproduce sexually inherit mitochondrial organelle from their mother
true
84
mitochondrial genes cannot be -- because all mitochondria are inherited from the mother
recessive
85
-- is involved in the synthesis of phosphatidylcholine
smooth ER
86
examples of plastids
chloroplast and chromoplast
87
-- are site of manufacturing and storage of important chemical compounds used by the cell and often contain pigments used in photosynthesis
plastids
88
plastids like prokaryotes contain a -- double-stranded DNA molecule
circular
89
mitochondrial mutations are often limited to one -- type
tissue
90
thyroid gland synthesizes -- in response to high blood calcium levels
calcitonin
91
calcitonin acts to reduce blood calcium, opposing the effects of --
parathyroid hormone
92
calcitonin lowers blood Ca2+ by inhibiting the absorption of Ca2+ by --
intestines
93
calcitonin lowers blood Ca2+ by inhibition of -- activity in bones
osteoclast
94
calcitonin lowers blood Ca2+ by inhibition of renal tubular reabsorption of Ca2+, allowing it to be --
excreted in urine
95
kidneys are essential in the urinary system and serve homeostatic functions such as the regulation of -- , maintenance of pH balance, and regulation of blood pressure (via salt and water balance)
electrolyes
96
kidneys secrete -- (involved in blood pressure regulation) that induces the release of aldosterone from the adrenal cortex
renin
97
secretion of renin -- blood pressure via sodium reabsorption
increases
98
PTH -- blood calcium
increase
99
high levels of Ca2+ in bone and kidney involves -- receptor
PTH 1
100
high levels of Ca2+ in CNS, pancreas, testes, and placenta involves -- receptor
PTH 2
101
largest organ
liver
102
T/F: liver function includes detoxification, protein synthesis, and production of biomolecules necessary for digestion
true
103
liver synthesizes -- which emulsifies lilies in the small intestine
bile
104
rough ER is involved in the synthesis of -- proteins
plasma membrane
105
active protein involves a -- and uses energy to move a substance across a membrane agains (up) a concentration gradient
carrier protein
106
refers to how some ionic species can pass through the barrier while others cannot
Donnan equilibrium
107
the presence of a different charged substance that is unable to pass through a membrane creates an --; the electrical potential arising between the solution is the Donnan potential
uneven electrical charge
108
overexpression of cyclin D promotes an unschedules entry into --
S phase
109
synthesis of cyclin D is initiated during -- and drives the G1/S phase transition
G phase
110
biochemical events lead to characteristic cell changes (morphology) and death which include -- (irregular bulge in plasma membrane), cell shrinkage, chromatin condensation, nuclear fragmentation and chromosomal DNA fragmentation
blebbing
111
programmed cell death
apoptosis
112
traumatic cell death that results from acute cellular injury, whereas apoptosis conferees advantages during an organism's life cycle
necrosis
113
unlike necrosis, apoptosis produces cell fragments called -- that phagocytic cells are able to engulf and quickly remove before the contents of the cell can spill out onto surrounding cells and cause damage
apoptotic bodies
114
a failure in which stage of spermatogenesis produces nondisjunction that results in a male having a XXY?
anaphase I
115
During meiosis anaphaseI, -- separate
homologous chromosomes
116
During meiosis anaphase II, -- separate
sister chromatids (identical copies, except for recombination)
117
In sperm, X and Y would be "homologous chromosomes" and would normally separate during meiosis I; failure to do so would create a sperm containing both X and Y which causes --
Klinefelter syndrome
118
Anaphase is when the -- splits and the homologous chromosomes/sister chromatids are drawn away (via spindle fibers) from each other toward opposite sides
centromere
119
-- is observed in females due to a single X karyotype (single X chromosome and lacking a Y)
Turner's syndrome
120
protein targeting occurs during the synthesis of which type of proteins?
secreting proteins
121
most proteins that are secretory, membrane-bound, or targeted to an organelle use the -- sequence of the protein to target the protein
N-terminal signal sequence (5-30 amino acids)
122
the signal sequence of the polypeptide is recognized by a -- while the protein is still being synthesized on the ribosome
signal recognition particle (SRP)
123
protein synthesis pauses while the -- is transferred to an SRP receptor on the ER (in eukaryotes) or to the plasma membrane (in prokaryotes) before translation of the polypeptide resumes
ribosome-protein complex
124
free ribosomes produce proteins in the --
cytosol
125
attached ribosomes produce proteins that are inserted into the --
ER lumen
126
the concentration of growth hormone receptors will significantly reduce after selective destruction of --
plasma membrane
127
all anterior pituitary hormones including GH are -- hormones
peptide hormones
128
peptide hormones are hydrophilic and cannot pass across the hydrophobic phospholipid bilayer, and therefore peptide hormones bind to receptors on the --
plasma membrane
129
urea, a byproduct of amino acid metabolism, is a small uncharged molecule and therefore crosses the cell membrane by --
simple diffusion
130
export of Na+ from a neuron is coupled with the import of --
K+
131
the sodium-potassium-ATPase pump (ATP dependent process) is necessary for the maintenance of a -- across the neuron membrane
voltage potential
132
movement of Ca2+ into a muscle cell occurs against the concentration gradient and Ca2+ enters by -- which requires ATP
active transport
133
synaptic vesicles contain -- and their exocytosis at a nerve terminus is an ATP-dependent process that is triggered by an action potential propagating along the neuron
neurotransmitters
134
p53 is a tumor suppressor protein that regulates the cell cycle and prevents --
cancer
135
-- is 1/2 the mass of carbon and is a unit of convention for expressing the molecular mass of proteins
Dalton
136
newly synthesized secretory protein: .... --> exterior of cell via exocytosis
rough ER, Golgi, secretory vesicles
137
cholesterol is normally found dispersed in varying amounts throughout animal cell membranes in the irregular spaces between the -- of the membrane
hydrophobic tails
138
cholesterol -- fluidity of the membrane because it confers stiffening and strengthening effects on the membrane
decreases
139
proteins targeted to the Golgi from the rough ER have three destinations: --, transported into organelles or targeted to the plasma membrane as a receptor, channel or pore
secreted out of the cell
140
the presence of -- differentiates a protein from a carbohydrate molecule
nitrogen
141
most abundant plasma protein
albumin
142
because albumin is too large to pass from the circulatory system into the interstitial space, it is primarily responsible for the -- of the circulatory system
osmotic pressure
143
osmotic pressure is the force of H2O to flow from an area of -- solute to -- solute concentration
lower solute to higher solute concentration
144
capillaries are -- to albumin
impermeable
145
increasing albumin solute concentration in the arteries/capillaries increases the movement of H2O from the interstitial fluid to -- the osmotic pressure in the arteries/capillaries
reduce
146
retinoblastoma protein (pRb or RB1) is a -- that is dysfunctional in several major cancers
tumor suppressor protein
147
one function of RB1 is to prevent -- by inhibiting cell cycle progression until a cell is ready to divid
excessive cell growth
148
RB1 also recruits several -- such as methylases and acetylases
chromatin remodeling enzymes
149
-- prevents cells from replicating damaged DNA by preventing its progression along the cell cycle through G1 into S phase
RB1
150
glycolysis occurs in the --
cytoplasm
151
oxidation of pyruvate into acetyl-CoA and the Krebs (TCA) cycle occur in the --
mitochondrial matrix
152
ETC (cytochrome) occurs in the --
inner membrane of the mitochondria
153
ETC (H+ proton gradient) occurs in the --
inter membrane space of the mitochondria
154
pyruvate is oxidized to acetyl-CoA as a preliminary step before joining -- in the Krebs cycle, which occurs in the mitochondrion
oxaloacetate
155
most abundant lipid in the body
triglycerides
156
minerals (potassium, sodium, calcium, magnesium) are essential nutrients because they must be consumed in the diet and act as -- (nonorganic components) for enzymes
cofactors
157
T/F: minerals are digested by lysosomes
false
158
recycling of organelles within the cell is accomplished through -- by the lysosomes
autophagy
159
albumins are -- proteins
globular
160
T/F: carotenoids and lecithin are lipid derivatives
true
161
defective attachment of a chromosome to the spindle blocks the activation of the -- complex
anaphase promoting
162
in meiosis II, human cells have a single -- copy of the genome
unreplicated
163
centrioles are cylindrical structures composed mainly of --found in most eukaryotic cells (except flowering plants and fungi)
tubulin
164
centrioles are involved int eh organization of the mitotic spindle and in the completion of --
cytokinesis
165
centrioles contribute to the structure of the -- and are involved in organizing microtubules in cytoplasm
centrosomes
166
position of the centriole determines the position of the -- and plays a crucial role in the spatial arrangement of the cell
nucleus
167
-- are the organizational sites for microtubules (i.e. spindle fibers) that assemble during cell division
centriole
168
cAMP is a -- triggered when a ligand (peptide hormone or neurotransmitter) binds to a membrane-bound receptor
second messenger
169
through a G-protein intermediate, the -- is activated and converts ATP into cAMP
adenylate cyclase
170
adenylate cyclase is attached to the inner layer of the --
phospholipid bilayer
171
placed in a hypertonic solution, erythrocytes will undergo -- as osmotic pressure draws water out of the cell and the cell shrivels
crenation
172
peroxisomes are abundant in the --
liver
173
-- are hollow proteins composed of tubulin monomers
microtubules
174
microtubules are necessary for the formation of the -- that separates chromosomes
spindle
175
T/F: microtubules are necessary for the synthesis of cilia and flagella
true
176
T/F: microtubules are necessary for the formation of the cell cytoskeleton within the cytoplasm
true
177
actin and myosin are -- fibers in muscle cells
contractile
178
actin and myosin are composed of --
microfilaments
179
a cell division where each of the two daughter cells receives a chromosome complement identical to that of the parent is --
mitosis
180
-- interfere with microtubule formation
colchicine
181
amoeboid moves using pseudopodia which are bulges of cytoplasm powered but eh elongation of flexible -- not microtubules
microfilaments
182
microtubules are long, hollow cylinders made up of polymerized alpha and beta --
dimers
183
T/F: apoptosis occurs both in fetal development and during ageing
true
184
high level of DNA synthesis occur in cells such as -- cells that use mitosis for rapid reproduction
skin cells
185
coat-proteins like -- are used to build small vesicles to safely transport molecules within and between cells
clathrin
186
clathrin is a protein that is collected on the -- side of the cell membrane and functions in the coordinated pinching off of membrane into receptor-mediated endocytosis
cytoplasmic
187
a lipid-soluble toxin that inactivates clathrin results in -- delivery of polypeptide hormones to endosomes
reduced
188
in osmosis, H2O always flows from a region of -- osmotic pressure to a region of -- osmotic pressure
lower to higher
