Unit 2 - Cell Structure and Function Flashcards
1
Q
higher solute concentration
A
hypertonic
2
Q
lower solute concentration
A
hypotonic
3
Q
equal solute/solvent concentration
A
isotonic
4
Q
diffusion of free water across a selectively permeable membrane
A
osmosis
5
Q
the total solute concentration in a solution
A
osmolarity
6
Q
Water moves by osmosis into the area with a _______ _______ concentration.
A
HIGHER solute
7
Q
Water concentrations and solute concentrations are _______ related
A
inversely
8
Q
Water would diffuse out of a ________ environ. –> _______ environ.
A
hypotonic, hypertonic
9
Q
Solutes diffuse along their own concentration gradients, __________ environ. –>_________ environ.
A
hypertonic, hypotonic
10
Q
In plant and animal cells, osmoregulation maintains ______ balance and allows _______ of internal solute composition/water ________
A
water, control, potential
11
Q
LESS cellular solute and MORE cellular water
A
environmental hypertonicity
12
Q
EQUAL solute and water
A
isotonic solution
13
Q
MORE cellular solute and LESS cellular water
A
environmental hypotonicity
14
Q
What is a plant cell’s state in environmental hypertonicty?
A
Plasmolysis
15
Q
the process in which cells lose water in a hypertonic solution
A
plasmolysis
16
Q
What is a plant cell’s state in isotonic solution?
A
flaccid
17
Q
cell lacking turgidity
A
flaccid
18
Q
What is a plant cell’s state in environmental hypotonicity?
A
turgid
19
Q
OPTIMUM STATE FOR PLANT CELLS
A
turgidity
20
Q
Water flows into the plant vacuoles via ________ causing vacuoles to _______ and press against the cell wall
The cell wall expands until it begins to exert the pressure back on the cell, this pressure is called ____________ __________
A
osmosis, expand, turgor pressure
21
Q
______ _____ maintains homeostasis for plant in environmental hypotonicity
A
Cell wall
22
Q
What is an animal cell’s state in environmental hypertonicty?
A
shriveled
23
Q
What is an animal cell’s state in isotonic solution?
A
normal
24
Q
What is a animal cell’s state in environmental hypotonicity?
A
lysed
25
External environments can be _________, ________, or ________ to the internal environment of cells.
hypertonic, hypotonic, isotonic
26
Water moves by OSMOSIS from areas of ______ osmolarity/solute concentration to areas of ______ osmolarity/solute concentration.
LOW, HIGH
27
Growth and homeostasis are maintained by the _________ movement of molecules _______ membranes.
constant, across
28
Osmoregulation maintains ________ balance and allows organisms to control their _______ _______ compostion
water, internal solute
29
measures tendency of water to move by osmosis
Water potential
30
Water potential is calculated from __________ potential and _________ potential
pressure, solute
31
Water moves by ________ from an area of ________ water potential --> _____ water potential
osmosis, HIGH, LOW
32
Water moves by ________ from an area of ________ solute potential --> _____ solute potential
osmosis, HIGH, LOW
33
Values of water potential can be ________, _________, or _________
positive, negative, zero
34
The more _______ water potential is, the ______ likely it is to move into an area
negative, more
35
Osmoregulation allows organisms to control what 2 things?
internal solute composition, water potential
36
As solute potential increases, water potential ___________.
descreases
37
As pressure potential increases, water potential ___________.
increases
38
As pressure potential decreases, water potential ___________.
decreases
39
In an ________ system the pressure potential is ZERO --> water potential ______ solute potential
OPEN, equals
40
Small molecules pass ______ across a cell membrane
freely
41
What are three examples of small molecules that can pass across a membrane?
N2, O2, CO2
42
movement of molecules from high concentration to low concentration
diffusion
43
Small amounts of very ______ molecules, like water, can diffuse across a cell membrane
polar
44
movement of molecules from high concentration to low concentration through TRANSPORT PROTEINS
facilitated diffusion
45
the diffusion of water across a selectively permeable membrane
osmosis
46
Large quantities of water move via ____________.
aquaporins
47
Differences in relative solute concentrations can facilitate _________
osmosis
48
net movement of molecules down their concentration gradient
passive transport
49
the movement of molecules against their concentration gradient
active transport
50
Active transport moves molecules and or ions against their concentration gradient from _____ concentration to _____ concentration
LOW, HIGH
51
carrier proteins used in active transport
protein pumps
52
Active transport requires _________ energy (such as ATP).
metabolic
53
Active transport establishes and maintains ___________ __________.
concentration gradients
54
Name the process:
The cell uses energy to take in macromolecules and particulate matter by forming new vesicles derived from the plasma membrane
endocytosis
55
Name the process
The cell's internal vesicles use energy to fuse with the plasma membrane and secrete large macromolecules out of the cell
exocytosis
56
What are the three types of endocytosis?
Phagocytosis, pinocytosis, receptor-mediated endocytosis
57
_________ ________ is the net movement of molecules from high concentration to low concentration without direct input of metabolic energy.
Passive transport
58
Via simple diffusion, water is transported in ____ amounts
small
59
Via facilitated diffusion, water is transported in ________ amounts through _________
large, aquaporins
60
______ ________ requires the direct input of energy to move molecules from regions of low concentration to regions of high concentration.
active transport
61
Large molecules and large molecules are moved INTO the cell by ________.
endocytosis
62
Large molecules and large molecules are moved OUT OF the cell by ________.
exocytosis
63
Phospholipids are _____________.
amphipathic
64
Phospholipids have a _________ ________ head and _______ ___________ tail.
polar hydrophillic, nonpolar hydrophobic
65
Phospholipids spontaneously forms a ______ in an AQUEOUS environment
bi-layer
66
Selective permeability is a direct consequence of ________ ______
membrane structure
67
What are the two types of transport proteins?
channel and carrier
68
What type of transport protein spans membrane and changes shape to bring molec. into cell?
carrier
69
What type of transport protein is a hydrophilic tunnel that allows small molecules to move through?
channel
70
What cell organelle:
- is the boundary between cell and environment
- controls transport of materials in and out cell
cell membrane
71
What are the two types of embedded protein?
peripheral and integral
72
Embedded proteins can be _______ or ________.
hydrophilic or hydrophobic
73
an embedded protein that is loosely bound to the exterior of the cell membrane
peripheral protein
74
A peripheral protein is HYROPHILIC with ______ ______ _______ groups
charged polar side
75
A peripheral protein is HYDROPHILIC with ______ ______ _______ groups
charged polar side
76
an embedded protein that spans the cell membrane
integral protein
77
A peripheral protein is:
- HYDROPHILIC with ______ ______ _______ groups
- HYDROPHOBIC with ______ side groups
and:
__________ hydrophobic interior of bilayer
charge polar side, nonpolar, penetrates
78
The structure of the cell membrane is called a ________ _______. It is not _______ because it is joined by _________ interactions, which are weaker than covalent bonds.
fluid bilayer, static, hydrophobic
79
A steroid type found between phospholipid layer and cell surface
cholestrol
80
regulates bilayer fluidity under different conditions
cholesterol
81
Diversity and loca. of carbs and lipids enable them to function as _____________.
markers
82
What are the six functions of embedded proteins?
(1) Transport
(2) Cell-cell recog.
(3) Enzymatic activity
(4) Signal transduction
(5) Intercellular joining
(6) Attachment for extracellular matrix or cytoskeleton
83
A protein that forms an ion channel through a membrane is most likely
a transmembrane protein
84
_______ function as recognition sites for interactions between cells
glycolipids
85
______________ is the driving force for BOTH facilitated and simple diffusion.
Concentration gradient
86
a passive process during which molecules move from a region of higher to lower concentration
Diffusion
87
What is the cholesterol in the cell membrane?
It stabilizes the cell membrane
88
composed of ribosomal RNA and protein. They help to synthesize proteins.
ribosomes
89
provides mechanical support and plays a role in intracellular transport 🚕
endoplasmic reticulum (ER)
90
What are the two types of ER?
Rough and smooth
91
helps to compartmentalize the cell and helps to carry out protein synthesis in the ribosomes.
Rough ER
92
helps in detoxification and lipid production
Smooth ER
93
- a membrane-bound organelle that is composed of several flattened membrane sacs
- vital in the final stages of preparing a protein. - helps correctly folding and modifying protein as needed
- packages 📦 proteins
Golgi Complex
94
- helps with ATP production
- has a small set of its own DNA 🧬
- a double membrane organelle
- its outer membrane is a smooth phospholipid bilayer
- its inner membrane is highly convoluted, (highly folded) which increases the surface area for a growing number of electron transport chains
Mitochondria
95
The mitochondria's increase in _____ ________ facilitates the production of ATP.
surface area
96
Where does cellular respiration occur?
mitochondria
97
What is the first step of cellular respiration?
It occurs with or without _____.
It does NOT occur in the ______.
glycolysis; oxygen; mitochondria
98
After the completion of glycolysis, the rest of cellular respiration occurs in the ___________, given that __________ is present.
mitochondria; oxygen
99
Where does the Citric Acid/Krebs Cycle occur?
matrix of mitochondria
100
Oxidative phosphorylation, with the help of the electron transport chain, occurs in the _______ ________.
inner membrane (of mitochondria)
101
- membrane-enclosed sacs that contain hydrolytic enzymes
- these enzymes = digestive enzymes --> help to break down 🚮 excess or worn-out cell parts
- help with programmed cell death ☠️, apoptosis
lysosomes
102
- a membrane-bound sac that has many different roles including:
storage + release of macromolecules and waste
vacuole
103
Plants 🌱 have a specialized large central vacuole that also serves many functions. The primary function of the large central vacuole is ____ ______.
water retention
104
Water retention is important for _____ ______.
turgor pressure
105
- photosynthetic algae and plants contain specialized organelles that can photosynthesize (capture, store, and use solar energy ⚡️) and make simple sugars
- have double membrane and thylakoids = flattened sacs with a phospholipid bilayer.
chloroplasts
106
Plants cells have BOTH chloroplasts AND _________
mitochondria
107
Where does photosynthesis occur?
chloroplast
108
What are the two stages of photosynthesis?
light-dependent ☀️ and light-independent 🌓
109
The light-DEPENDENT reaction of photosynthesis occurs in the _______ and produces the _____ and ______ necessary for the light-independent reaction.
grana; ATP, NADPH
110
The light-INDEPENDENT reaction of photosynthesis is where the _______ ______ takes place and ______ is fixed to make simple ______.
Calvin-Benson, carbon, sugars
111
In what type of microscopy are animal cells visible?
light
112
type of electron microscopy - slices through nucleus with a diamond blade
transmission
113
type of electron microscopy - scans electrons on surface of cell and produces 3D image of organelles
scanning
114
What is the only thing that can leave the nucleus?
RNA
115
Animal cells have multiple mito_______.
Plant cells have multiple chloro_______ and mito_________.
chondria; plasts, chondria
116
What is the biggest organelle in the plant cell?
central vacuole
117
Eukaryotic vs Prokaryotic:
- DNA
- Ribosomes
- Golgi and ER?
Eukaryotic | Prokaryotic
- contained in membrane | - free
- regular | - smaller 70s rib.
- yes | - no
118
Free living prokaryotic cells ate by primitive pro-eukaryotic cells to become mitochondria and chloroplasts seperately
endosymbiotic theory
119
a membrane bound sac
vesicles
120
What is the shape of vesicles, including vacuoles, contractile vacuoles, lysosomes, and peroxisomes?
circle
121
large vesicle, function varies; found in animal and plant cells
vacuoles
122
found in protists and other things; helps regulate temperature in paramecium
contractile vacuole
123
vesicle with enzymes that remove H+ found in plants and animals
peroxisomes
124
What human organs should have a higher amount of peroxisomes?
1. Liver
2. Kidney
3. Lungs
125
Both chloroplasts and mitochondria have their own ______.
DNA
126
type of phospholipid in phospholipid bilayer/cell membrane:
- one or more double bonds create a "kink" or bend that pushes phospholipids in cell membrane apart and make more liquidy
unsaturated
127
Kinks make the cell _______.
weaker
128
The more compact your membrane is, the more ______ it is.
sturdy
129
type of phospholipid in phospolipid bilayer/cell membrane:
- normal and no kinks
saturated
130
Low temperatures cause phospholipids to draw closer to each other. Cholesterol pushes the phospholipids _______ from each other.
away
131
Higer temperatures cause phospholipids to drift farther from each other. Cholesterol pushes the phosphlipids ________ to each other.
close
132
What does cholesterol do for the cell membrane?
Stabilizes it
133
At low temperatures, cholesterol prevents the membrane from ______.
hardening
134
At high temperatures, cholesterol keeps membrane _______.
solid
135
_______, ________ molecules can pass through the cell membrane through simple diffusion
small, hydrophobic (non-polar)
136
channel proteins that only allow water in (passive transport)
aquaporin
137
not really an organelle - a clump of DNA that produces ribosomes
nucleolus
138
The inside of a transport protein is likely to be ________.
hydrophillic
139
Protein CHANNELS allow ______, ______ molecules or polar molecules to cross the plasma membrane. __________ amino acids will line the inner portion of the channel to allow this movement.
small, charged, hydrophillic
140
What three organelles display folded structures which allows them to function more efficiently?
The Golgi complex, mitochondria, chloroplast, and endoplasmic reticulum (ER)
141
Prokarya do not have ____________ or __________.
mitochondira, chloroplasts
142
Facilitated diffusion is an example of _________ transport. The movement of water across a cell membrane _______ require energy but it is facilitated or helped through _______ membrane proteins.
passive, doesn't, aquaporin
143
A mutation causes the membrane of a lysosome to become leaky. Describe a result of this:
Hydrolytic enzymes leak into the cytoplasm causing digestion of vital proteins.
144
The lysosomal membrane separates __________ enzymes from the _______. Without this membrane, hydrolytic enzymes are capable of __________ essential components in the cytosol.
hydrolytic, cystol, destroying
145
This organelle contains a double membrane which provides compartmentalization to separate different metabolic reactions
mitochondria
146
The water potential of pure water is:
0
147
PURE water DOES NOT contain any _______. As solutes are added to a solution, water potential becomes MORE ______.
solute, negative
148
epidermal pores on a plant's surface that are essential for the control of water balance in plants
stomata
149
- located in the leaf epidermis
- form stomatal pores, which regulate CO2 influx from the atmosphere into the leaves for photosynthetic carbon fixation
- regulate water loss of plants via transpiration to the atmosphere by closing/opening stomata
guard cells
150
Osmoregulation in plants occurs by
the work of guard cells
151
the process of regulating water potential in order to keep fluid and electrolyte balance within a cell or organism relative to the surrounding
osmoregulation
152
The membrane of the chloroplast is _______ permeable.
FREELY
153
stacks of thylakoids
grana
154
the site of photochemical or LIGHT-DEPENDENT reactions of photosynthesis
thylakoid
155
Increased folding increases efficiency for________ __________ reactions, and all reactions in the chloroplast.
light-dependent
156
Fluid between the inner chloroplast membrane and outside thylakoids
CARBON FIXATION (CALVIN CYCLE) REACTIONS OCCUR HERE
stroma
157
________ captures energy from macromolecules.
Mitochondria
158
Some viral infections can lead to the rupture of the lysosome membrane. Which prediction of the effect of this disruption of cellular compartmentalization is most likely correct?
Hydrolytic enzymes will be released, which will cause cell death.
159
Gaucher disease is an inherited disorder in which cells of the body are unable to break down a particular type of lipid, resulting in a buildup of the lipid in some tissues and organs.
Based on the information provided, Gaucher disease results most directly from a defect in the function of which of the following organelles?
The lysosome
160
The _________ contains specific enzymes used to break down a variety of molecules and cellular waste products.
lysosome
161
Testosterone is a small steroid hormone that is important in cell signaling. Which of the following describes where testosterone enters a cell and why it is able to cross at that point?
testosterone is nonpolar and can diffuse through the membrane.
162
Researchers investigate the transport of a certain protein into cells by endocytosis. In an experiment, the researchers incubate the cells in the presence of the protein and measure the amount of the protein that is absorbed into the cells over a five-minute period.
Based on their observations, what should the researchers do to further clarify how the availability of the protein outside the cells affects the rate of endocytosis of the protein?
Incubate the cells in the presence of several different concentrations of the protein.
163
Which of the following transport mechanisms will be affected most directly by a temporary shortage of ATP molecules inside the cell?
The transport of glucose molecules against a concentration gradient
164
Photosynthesis is a process used by both _________ and some _________.
eukaryotes (algae and plants), prokaryotes (cyanobacteria)
165
Which of the following observations best supports the claim that mitochondria evolved from once-free-living prokaryotic cells by the process of endocytosis?
Mitochondria has a double membrane
166
The double membranes of mitochondria provide evidence that an ancestor of mitochondria, which was most likely a type of free-living ______ ________, was ingested via endocystosis by a ________ eukaryotic cell.
aerobic bacterium, primitive
167
Beetroot cells contain a family of dark red pigments called betalains. The selectively permeable nature of the beetroot cells keeps the internal environment of the cell separate from the external environment of the cell. Researchers are interested in determining whether the selective permeability of beetroot cells is due to the cell membrane or if it is due to the cell wall.
Exposure to cellulase is known to damage the structure of the cell wall. An experiment is set up in which beetroot cells are placed in an aqueous solution with cellulase and in one without cellulase.
Which of the following results best refutes the alternative hypothesis that selective permeability is a consequence of the cell wall?
When beetroot cells are placed in a solution with cellulase, the solution remains clear.
168
Cellulase digests _______ and damages the structure of the cell _____, not the cell ________. The lack of color change in the solution indicates that the betalain is not leaking out of the beetroot cells even though the cell wall has been damaged. This refutes the alternative hypothesis.
cellulose, wall, membrane
169
Why do the hydrolytic enzymes released by lysosomes when they fuse with damaged organelles do not continue to act on other health functioning organelles are the targeted organelle is broken down and recycled?
Enzymes of lysosomes = acidic pH for functional shape
alkaline pH of cytosol quickly denatures them
170
A researcher studying membrane dynamics fuses two small cubiodal cells together to form one cell. What happens to the cell due to the altered SA:V?
The cell will have difficulty taking in and eliminating nutrients and waste materials.
171
The HYDROPHOBIC tails of the cell membrane phospholipid bilayer prevent large quantities of ______ from entering the cell without _______ _______.
water, transport proteins
172
The HYDROPHILLIC heads of the cell membrane phospholipid bilayer allow large quantities of ______ from entering the cell without _______ _______.
small, nonpolar molecules; transport proteins
173
Potassium ions (K+) will use ______ diffusion to travel ACROSS GRADIENT to the less concentrated, HYPOTONIC cell solution
facilitated
174
Potassium ions (K+) will use ______ _______ to travel AGAINST GRADIENT to the concentrated, HYPERTONIC cell solution
active transport
