TEAS 7 - Science (Parts of the Cell) Flashcards
1
Q
What are the 3 main parts of every cell?
A
- cell membrane
- cytoplasm
- nucleus
2
Q
The cell ___ is the outer layer of the cell.
A
cell membrane
3
Q
The cell membrane is the ___ layer of the cell. It is made up of a thin, flexible layer of ___ and ___ that surrounds the cell and controls what goes in and out of the cell, acting like a gatekeeper.
A
outer
lipids
proteins
4
Q
The ___ is a gel-like substance that fills the inside of the cell. It is made up of water, salts, and various types of molecules, including proteins, enzymes, and nutrients. This is also where all the cell’s main organelles are found and where many of the cell’s metabolic reactions take place.
A
cytoplasm
4
Q
What are specialized structures inside the cytoplasm that perform essential functions in the cell?
A
organelles
5
Q
The ___ are the organelles responsible for producing energy in the cell. They are often called the “powerhouses” of the cell.
A
mitochondria
6
Q
The ___ ___ is a network of membranes that helps to transport proteins and other molecules throughout the cell.
A
Endoplasmic Reticulum
7
Q
The ___ ___ is another membrane-bound organelle that helps to process and package proteins for transport within and outside the cell.
A
Golgi Apparatus
8
Q
___ are small organelles that contain enzymes to break down waste and other cellular debris.
A
Lysosomes
9
Q
The nucleus also contains the ___, which is responsible for making ribosomes, the cell’s protein-making factories.
A
nucleolus
10
Q
The ___ is a network of protein fibers that help to give the cell its shape and provide support.
A
cytoskeleton
11
Q
The ___ is a membrane-bound organelle found in eukaryotic cells that contains the genetic material of the cell.
A
nucleus
12
Q
What acts as the control center of a cell, regulating all the cell’s activities by directing the synthesis of proteins and other important molecules?
A
the nucleus
13
Q
The nucleus contains the cell’s ___, which is organized into chromosomes.
A
DNA
14
Q
Chromosomes are made up of ___, which are the basic units of heredity.
A
genes
15
Q
Genes contain instructions for making ___, which are the building blocks of the cell and carry out many important functions.
A
proteins
16
Q
How are DNA, genes, chromosomes, and proteins related?
A
Genes are segments of DNA –>
DNA is organized into chromosomes –> Genes (which are segments of DNA and are part of chromosomes) contain instructions for making proteins –>
proteins are building blocks of cells
17
Q
In addition to containing DNA, the nucleus also contains a dense structure called the ___.
A
nucleolus
18
Q
What is the nucleolus responsible for?
A
for assembling RNA and proteins into ribosomes
19
Q
A cell’s DNA is organized into ___.
A
chromosomes
20
Q
Instructions for making proteins are located in the ___.
A
genes
21
Q
What is the jelly-like substance that fills the inside of eukaryotic cells?
A
cytoplasm
22
Q
One of the main functions of the ___ is to provide a medium for cellular activities. It acts as a space where many of the cell’s chemical reactions occur. It contains important molecules, such as proteins, carbohydrates, and ions, that are needed for the cell’s metabolism, growth, and reproduction.
A
cytoplasm
23
Q
Additionally, the cytoplasm plays a role in intracellular ___. It provides a medium for molecules and organelles to move within the cell.
A
intracellular transport
24
___ is a type of organelle also known as the “powerhouse of the cell” because it creates the energy (ATP) used by the cell to carry out its functions.
Mitochondria
25
When an organelle can replicate and express its own DNA, we call it ___-___.
semi-autonomous
26
___ is a process that occurs in the mitochondria of cells where the movement of ions across a selectively permeable membrane creates a gradient that is used to generate ATP (adenosine triphosphate)
Chemiosmosis
27
Mitochondria have a double layer of membrane, where the outer layer is smooth and made of lipids, while the inner layer is folded into little finger-like structures called ___.
cristae
28
What is the purpose of cristae in mitochondria?
they give the inner membrane a lot of surface area for energy production
29
Special enzymes in the inner membrane use this surface area to make a molecule called ___, which is like a battery for our cells.
ATP
30
The space between the two layers of the membrane is called the ___ ___, while the space inside the inner membrane is called the ___.
intermembrane space
matrix
31
Where does chemiosmosis take place?
intermembrane space
32
Chemiosmosis is the process where the energy made during ___ ___ is used to move hydrogen ions across the inner membrane of the mitochondria, creating a proton ___.
cellular respiration
proton gradient
33
What does ATP synthase make?
ATP
34
This proton gradient is used by another special enzyme called ___ ___ to make ATP.
ATP synthase
35
35
Mitochondria have their own ___ and it is ___ from the cell’s nuclear DNA.
DNA
separate
35
This genetic material is found in the form of a small circular DNA molecule, called the ___ ___ (mtDNA).
mitochondrial DNA
36
What shape is mitochondrial DNA (mtDNA)?
small, circular DNA
37
Since the mitochondria has its own DNA, this means that mitochondria can replicate and express their own genes, making them ___-___.
semi-autonomous
38
What does it mean when we say that mitochondria are semi-autonomous?
mitochondria have their own DNA, so they can replicate and express their own genes
39
Mitochondria also all have their own ribosomes and can make their own ___.
proteins
40
The proteins synthesized by the ___ are mostly involved in the production of energy.
mitochondria
41
What is cell death called?
apoptosis
42
Mitochondria play a key role in cell death, also known as ___. Apoptosis is a ___ process that occurs in cells in response to certain signals, such as DNA damage or viral infection.
apoptosis
programmed
43
When a cell receives these signals, the mitochondria release a group of proteins called ___ ___, which triggers a cascade of events that lead to the death of the cell.
cytochrome c
44
When would mitochondria release a group of proteins called cytochrome c?
cytochrome c triggers a cascade of events that lead to the death of the cell
45
Mitochondria are also responsible for ___ synthesis, specifically for energy production.
protein synthesis
46
What is the function of the mitochondria’s inner membrane?
Increase surface area for energy production
47
What is the process called that occurs in the mitochondria and generates ATP using a proton gradient?
Chemiosmosis
48
What feature of mitochondria makes them semi-autonomous?
Each mitochondrion has its own genome and ribosomes
49
What is the organelle found in eukaryotic cells that plays a key role in the modification, sorting, and transport of proteins and lipids?
Golgi Apparatus
50
___ is a flat structure located within the Golgi apparatus and in the endoplasmic reticulum that assists with the packaging of proteins.
Cisternae
51
___ are the large, complex macromolecules that are responsible for the structure, function, and regulation of our cells and tissues.
Proteins
52
52
___ are large, complex macromolecules that are responsible for the structure, function, and regulation of our cells and tissues.
Proteins
52
___ are the macromolecules that play many important roles such as providing energy to cells, protecting our organs, and helping to produce hormones.
Lipids
53
What is the number of Golgi "bodies" in a cell dependent on?
the function of that particular cell
54
What is the organelle is responsible for the modification, sorting, and transport of proteins and lipids within a cell?
Golgi Apparatus
55
Golgi bodies are responsible for the ___ made to proteins. Once proteins are delivered to the Golgi Apparatus, they may be modified (or changed).
changes (or modifications)
56
The Golgi is composed of a series of flattened, stacked ___, which are membrane-bound structures.
cisternae
57
The cisternae are organized into three regions: the ___-Golgi, ___-Golgi, and __-Golgi.
cis-Golgi
medial-Golgi
trans-Golgi
58
What other organelle is the cis-Golgi closest to?
endoplasmic reticulum (ER)
59
The cis-Golgi is the region closest to the ___ ___ (ER) and is responsible for receiving newly synthesized ___ and lipids from the ER.
endoplasmic reticulum
proteins
60
The ___-___ is the region between the cis-Golgi and trans-Golgi and is responsible for further modification of the proteins and lipids.
medial-Golgi
61
61
Which side of the cisternae faces away from the ER?
trans-Golgi
61
Which side of the cisternae is closest to the ER?
cis-Golgi
61
the ___ face, the side of the cisternae facing the Endoplasmic Reticulum (ER) which receives newly incoming proteins and lipids from the ER.
cis
62
The ___ face, the side of the cisternae facing away from the ER, sorts and directs the proteins and lipids to their final destinations.
trans
62
The ___ ___ (ER) is a network of interconnected sacs and tubules within the cytoplasm of an eukaryotic cell.
endoplasmic reticulum
63
The proteins are made by the ___ on the RER, and then undergo modifications and folding within the RER before being transported to their final destination.
ribosomes
63
Why is the RER called "rough?"
because it is studded with ribosomes
64
65
65
The SER plays a variety of roles, including ___ concentration and synthesis, ___ hormone synthesis, carbohydrate metabolism, and detoxification of drugs and poisons.
lipid
steroid
66
67
A ___ is a type of cellular organelle found in eukaryotic cells. It is a spherical, membrane-bound structure that contains a variety of hydrolases, which are enzymes that break down and digest cellular waste and damaged materials.
Lysosome
68
68
Cellular ___ refers to the maintenance of a stable and ___ internal environment within a cell. This internal environment includes factors such as the concentration of ions and nutrients, pH, and the presence of waste products.
homeostasis
balanced
68
A ___ is a double-membrane structure formed during the process of autophagy, which is a cellular degradation and recycling process.
Phagosome
69
Autophagy is a process of cellular degradation and ___.
recycling
70
71
___ is also known as programmed cell death.
Apoptosis
72
Apoptosis, also known as programmed cell death, is a process by which cells naturally ___-___ in a controlled and regulated manner.
self-destruct
73
What are considered the recycling centers of our cells?
lysosomes
74
Lysosomes are like the ___ centers of our cells. They play a very important role in keeping our cells healthy and functioning properly.
recycling
75
Think of our cells as tiny cities. Just like how cities need to get rid of their ___, our cells need to get rid of old and damaged materials too. That’s where ___ come in!
waste
lysosomes
76
Lysosomes contain special enzymes, called ___, that break down and recycle old or damaged materials in our cells, just like how recycling centers break down and reuse waste.
hydrolases
77
Hydrolases are enzymes that require a certain pH in order to function effectively. What is it?
pH of 5
78
79
Do lysosomes require a basic or acidic environment to survive?
acidid (pH of 5)
80
Lysosomes have an ___ environment with a pH of around ___.
acidic
5.0
81
The (low/high) pH of the lysosome provides the optimal environment for these enzymes to work and digest the contents within the lysosome, including cellular waste, damaged organelles, and bacteria.
low
82
When vesicles, called ___, containing cellular waste or damaged materials are delivered to the lysosome, the acidic environment within the lysosome activates the ___ and the contents of the vesicles are digested and recycled.
phagosomes
hydrolases
83
The pH of the lysosome is maintained by a ___ ___, which actively pumps hydrogen ions into the lysosome to keep the pH low.
proton pump
84
By breaking down and digesting cellular waste, lysosomes help to prevent the buildup of ___ materials within the cell.
harmful
85
What do lysosomes work with to ensure that cellular waste is processed and eliminated efficiently?
golgi apparatus
86
___ ___ refers to when the inside environment of the cell is stable and balanced.
Cellular homeostasis
87
What are two types of processes that cells can use to prepare materials that are targeted for digestion?
- endocytosis
- autophagy
88
Endocytosis is the process by which the cell ___ ___ materials and substances from ___ the cell, and then processes and digests them within the lysosome.
takes in
outside
89
___ is the process by which the cell takes in materials and substances from outside the cell, and then processes and digests them within the lysosome.
Endocytosis
90
___ is the process by which cells degrade and recycle their own cellular components, also facilitated by the lysosome.
Autophagy
91
Autophagy is the process by which cells degrade and recycle ___ ___ cellular components, also facilitated by the lysosome.
their own
92
When is an autophagosome formed?
during the process of autophagy
93
An ___ is a double-membraned vesicle that is formed during the process of autophagy.
autophagosome
94
Autophagy is a cellular process in which the cell identifies and engulfs its ___ damaged or unnecessary parts, such as proteins or organelles, into a double-membraned vesicle known as an ___.
own
autophagosome
95
Autophagy plays an important role in cellular homeostasis by making sure that damaged and unnecessary cell parts are ___ and ___.
removed and recycled
95
The autophagosome fuses with a ___, which digests and recycles the contents of that vesicle.
lysosome
95
When ___ are damaged they can become dysfunctional and fail to effectively digest and recycle cellular components.
lysosomes
96
When lysosomes are damaged, this can lead to the accumulation of cellular ___ and damaged materials, causing cellular ___ and potentially triggering ___.
waste
stress
apoptosis
96
Damage to lysosomes can lead to ___, which is programmed cell death.
apoptosis
96
In some cases, lysosomal damage can also trigger the release of lysosomal ___ into the cytoplasm, where they can activate apoptotic pathways and lead to cell ___.
contents
death
97
What disease is a lysosomal storage disease caused by a deficiency of the enzyme glucocerebrosidase?
Gaucher disease
98
What is the primary function of lysosomes in a cell?
cellular waste disposal
98
Which organelle is responsible for the synthesis and packaging of enzymes that are later transported to the lysosome?
Golgi apparatus
99
What is the optimal pH range for lysosomal enzymes to function effectively?
pH 4.5-5.0
100
Which of the following diseases is caused by a lysosomal storage disorder?
Gaucher disease
100
What happens to a cell when the lysosome is damaged or impaired?
it triggers apoptosis
101
The ___ is a network of filaments and tubules found in the cytoplasm that give the cell its shape.
cytoskeleton
102
Is the cytoskeleton an organelle?
No, it is made up of protein that provides shape, structure, and support of the cells
103
___ are protein (actin) filaments found in eukaryotic cells and assist in cell membrane motility, endocytosis, exocytosis, secretion, and vesicle transfer.
Microfilaments
103
What is interchangeable with the term "microfilaments?"
actin
104
What is interchangeable with the term "actin?"
microfilaments
105
The cytoskeleton is a complex ___ of protein fibers that provides the cell with shape, structure, and mechanical support.
network
105
___ are rigid, hollow rods that provide structure, help to move cells, organize genetic material during cellular division, and help with intracellular transport. Cilia and flagella are common types of microtubules.
Microtubules
106
___ ___ are filaments that provide structure and support for cells. They are also essential in anchoring the cell to other cells and to the extracellular matrix.
Intermediate fibers
106
One of the key functions of the cytoskeleton is to facilitate the ___ of materials within the cell.
movement
107
The cytoskeleton is composed of three main types of fibers. What are they?
microfilaments
intermediate fibers
microtubules
108
Microfilaments help the cell move by forming temporary extensions called ___.
pseudopodia
108
___, or actin filaments, are thin, flexible fibers made of the protein actin.
Microfilaments
108
Microfilaments, also known as ___ ___, are thin, flexible fibers made of the protein actin.
actin filaments
109
They are also important for moving organelles and other materials within the cell, which is called ___ ___.
cytoplasmic streaming
110
Microfilaments also play a very significant role during cellular replication and division, most notably during ___, when the cell splits into two ___ cells.
cytokinesis
daughter
110
Additionally, microfilaments can bundle together to help the cell keep its shape. They are like ___ pipes that run through a building.
shape
flexible
111
During cytokinesis, microfilaments contract and form a furrow in the ___ of the parent cell. The microfilaments form a ___ that gets smaller as they contract.
The cytoplasm is pinched until the ___ cell is split into two ___ cells.
middle
ring
original
daughter
112
During muscle contraction, the ___ filaments within the muscle fiber are pulled toward the center of the sarcomere, which is the basic unit of muscle contraction.
actin filaments
sarcomere
113
Intermediate fibers are ___ and more rigid than microfilaments (but not as thick as ___).
thicker
microtubules
113
Muscle contraction occurs due to the action of the protein ___, which forms cross-bridges with the ___ filaments and uses ___ energy to “walk” along the filaments and pull them toward the center of the sarcomere.
myosin
actin
ATP
114
___ ___ are thicker and more rigid than microfilaments (but not as thick as microtubules), and they provide the cell with mechanical strength and support.
Intermediate fibers
114
While intermediate fibers are ___ directly involved in the movement of materials within the cell, they provide a ___ framework that allows for the proper organization of other cytoskeletal elements.
not
stable
114
___ are long, tubular structures that play a critical role in maintaining the shape and organization of cells.
Microtubules
115
What are key components of the cytoskeleton, which form a network of protein fibers that provide structural support and help with cell division, movement, and communication?
Microtubules
116
Microtubules are made up of ___, which are pairs of protein subunits.
dimers
117
Dimers are arranged in a ___-___-___ fashion to form long chains, which then assemble into the cylindrical shape of a microtubule.
head-to-tail
117
Dimers, which make up microtubules, are pairs of protein subunits called ___-___ and ___-___.
alpha-tubulin
beta-tubulin
117
What is the shape of microtubules?
cylindrical shape
118
The formation of dimers is essential for___ stability and function. For example, when a microtubule is assembled, the dimers are positioned in a specific way that allows for the microtubule to ___ and ___ in a controlled manner.
microtubule
grow
shrink
119
The dimer formation allows proteins to ___ along the microtubules.
travel
119
Proteins that travel across microtubules are called ___ proteins.
motor
119
What are the names of the two motor proteins that travel along microtubules?
kinesins
dyneins
119
Kinesins move, or “walk”, toward the ___ end of the microtubule, while dyneins travel toward the ___ end.
positive
negative
120
What do kinesins and dyneins carry to their destinations?
these proteins typically carry vesicles to their destinations
121
___ move, or “walk”, toward the positive end of the microtubule, while ___ travel toward the negative end.
Kinesins
dyneins
122
Microtubules are also major components of the mitotic ___ fibers, which separate sister chromatids during ___.
spindle
mitosis
122
The binding of certain drugs or proteins to microtubules can ___ the formation of dimers or cause them to be misaligned.
This can alter the stability and function of the ___ and has important implications for medical research, as drugs that target microtubules can be used to treat diseases such as cancer and Alzheimer’s.
disrupt
microtubule
123
One end of the spindle fibers attaches to the center (___) of each sister chromatid, while the other end of the fiber attaches to one of the two ___ at each end of the cell.
kinetochore
centrosomes
124
The spindle fibers begin to ___ and pull the sister chromatids ___ to opposite ends of the cell.
shorten
apart
125
What are the three main types of fibers that make up the cytoskeleton?
Microfilaments, intermediate fibers, and microtubules
125
Which type of cytoskeletal fiber is responsible for cell movement and the formation of temporary cell extensions?
Microfilaments
125
What is the role of microfilaments during cell division?
They contract to form a furrow and split the cell into two daughter cells.
126
Which motor proteins move along microtubules and carry vesicles to their destinations?
Kinesins and dyneins
127
How do microtubules contribute to maintaining cell shape and organization?
The dimers that make up microtubules are organized in a head-to-tail orientation that forms strong chains
128
___ are tiny, hair-like structures that project from the surface of cells.
Cilia
128
___ are whip-like structures that protrude from the surface of certain cells and are used for locomotion or movement.
Flagella
129
___ are cylindrical organelles found in eukaryotic cells that play an important role in cell division.
Centrioles
130
Cilia and flagella are ___ hair-like structures that protrude from the surface of certain cells.
microscopic
130
___ are organelles found in eukaryotic cells that play a key role in organizing the microtubules within the cell.
Centrosomes
131
What are cilia and flagella composed of?
they are composed of microtubules
132
Cilia and flagella play important roles in cellular ___, ___ perception, and ___ movement.
movement
sensory
fluid
132
Flagella are typically ___ and ___ in number than cilia
longer
fewer
132
Flagella are used for motion called ___.
locomotion
133
For example, in bacteria, ___ rotate like propellers to move the cell through liquid environments, while in sperm cells, the ___ propels the cell toward the egg.
flagella
flagellum
134
Cilia, on the other hand, are ____ and more ___ than flagella.
shorter
numerous
135
What is typically longer and fewer in number? Flagella or cilia?
Flagella
136
What is shorter and more numerous? Flagella or cilia?
Cilia
137
___ can be found in many types of cells, including those in the respiratory tract, oviducts, and the brain.
In the respiratory tract, ___ help move mucus and foreign particles out of the lungs, while in the oviducts, ___ help move the egg toward the uterus. In the brain, ___ play a role in sensing and transmitting signals.
Cilia
cilia
cilia
cilia
137
The ___ is a crucial organelle that regulates the organization and growth of microtubules in a cell. Positioned near the nucleus, it serves as the microtubule organizing center
centrosome
137
The centrosome is composed of two cylindrical ___, which have a unique pattern of microtubule arrangement.
centrioles
137
What do two centrioles create?
a centrosome
138
When a cell divides, the centrosome duplicates and moves to ___ poles of the cell, where it plays a crucial role in organizing the microtubules that make up the mitotic spindle.
opposite poles
139
Centrioles are small, ___ structures found in most eukaryotic cells.
cylindrical
140
A pair of centrioles make up a ___.
centrosome
141
During cell division, centrioles ___ and move to opposite ends of the cell, where they help to organize microtubules into spindle fibers that attach to the ___ and pull them apart during cell division.
Remember, the centrioles are part of the ___.
duplicate
chromosomes
centrosomes
142
Defects in ___ function have been associated with a variety of human diseases, including cancer and ciliopathies, which are characterized by ___ in cilia and flagella formation and function.
centriole
defects
142
Centrioles have a ___ role. They play a role in organizing microtubules in the cytoplasm, for maintaining the cell’s ___ and supporting the ___ of cellular structures.
structural
shape
movement
143
What are cilia and flagella made of?
Microtubules
144
What is the difference between cilia and flagella in terms of their length and function?
Flagella are longer and used for locomotion, while cilia are shorter and more numerous.
145
Where can cilia be found in the human body, and what is their function?
In the respiratory tract, where they help move mucus and foreign particles out of the lungs
145
What is the role of flagella in bacterial cells?
To propel the cell through liquid environments
146
What is the main function of the centrosome?
To regulate the growth and arrangement of microtubules within the cell
147
What happens to the centrosome during cell division?
It duplicates and moves to opposite poles of the cell
147
The ___ ___, also known as the cell membrane, is a thin, semi-permeable membrane that surrounds and encloses the contents of a cell, acting as a barrier to the outside environment.
plasma membrane
147
What is the role of centrioles during cell division?
To organize microtubules into spindle fibers
147
A ___ is a type of lipid molecule that is an essential component of cell membranes. They are composed of a hydrophilic (water-loving) head and a hydrophobic (water-fearing) tail.
phospholipid
148
___ ___ are the proteins anchored within the plasma membrane.
Integral proteins
149
___ ___ are a type of membrane protein that form channels or pores in the cell membrane, allowing the passive diffusion of specific molecules or ions across the membrane
Channel proteins
150
___ ___ are a type of membrane protein that facilitates the movement of molecules across the cell membrane
Carrier proteins
151
The cell membrane, also known as the ___ ___, is a thin, flexible barrier that surrounds and encloses the contents of a cell.
plasma membrane
152
What is one of the primary functions of the plasma membrane?
to control the passage of substances into and out of the cell
153
The membrane is ___ permeable, meaning it allows ___ molecules, such as oxygen, carbon dioxide, and small hydrophobic molecules, to freely diffuse across it while restricting the passage of larger, polar, or charged molecules.
selectively permeable
certain
154
This selective permeability is due to the structure of the membrane, which is made of a bilayer of ___ molecules.
phospholipid
155
The hydrophobic ___ of the phospholipids face inward, while the hydrophilic ___ face outward, creating a barrier that separates the inside of the cell from the outside environment.
tails
heads
155
Phospholipids are ___, meaning they have both ___ (water-repelling) and ___ (water-loving) regions, which allows them to form a stable bilayer in an aqueous environment.
amphipathic
hydrophobic
hydrophilic
156
The hydrophobic tails of the phospholipids face ___, while the hydrophilic heads face ___.
inward
outward
157
Phospholipid heads are ___ and face ___ while phospholipid tails are ___ and face ___.
hydrophilic, outward
hydrophobic, inward
158
Another important function of the cell membrane is to facilitate cell-to-cell ___ and signaling.
communication
159
The membrane contains various receptors and proteins that allow the cell to ___ and ___ to external stimuli (hormones, neurotransmitters, pathogens, etc).
detect
respond
160
The cell membrane can form ___ with adjacent cells, which allow cells to ___ to each other and coordinate their activities, as in the case of tissues and organs.
junctions
adhere
161
The cell membrane also contains various ___ and proteins that allow it to withstand mechanical stress and ___ in temperature or pressure.
lipids
changes
162
The plasma membrane can also actively ___ molecules across the membrane, using energy from ___ or ion gradients, which is critical for various cellular processes such as nutrient uptake, waste removal, or signaling.
transport
ATP
163
The plasma membrane also plays a role in maintaining the ___ of the cell. The membrane is anchored to the ___, a network of protein filaments that provides support and shape to the cell.
structure
cytoskeleton
163
What is the primary function of the plasma membrane in a eukaryotic cell?
To control the passage of substances into and out of the cell
164
Which of the following describes the structure of a phospholipid?
It has two hydrophobic tails and one hydrophilic head
164
What type of protein forms channels in the plasma membrane to allow the passive diffusion of specific molecules?
Channel proteins
165
Which of the following best explains why the plasma membrane is selectively permeable?
The phospholipid bilayer allows only certain molecules to pass based on size and polarity
166
How does the plasma membrane contribute to cell-to-cell communication?
By containing receptors that detect and respond to external signals
167
What role do integral proteins play in the plasma membrane?
They are anchored within the membrane and assist in various functions such as transport and signaling
168
Which of the following functions are carried out by the nucleus?
The nucleus regulates the DNA transcription and translation process.
169
Which function of the plasma membrane requires energy from ATP?
Active transport of molecules across the membrane
170
Smooth endoplasmic reticulum helps in which of the following functions?
Smooth ER regulates the synthesis of various lipids and hormones.
170
Which of these is a function of the ribosome?
Ribosomes help in amino acid assembly and in the formation of peptide bonds.
171
Which of the following describes the structure of the endoplasmic reticulum?
The endoplasmic reticulum is an interwoven network of membranes that extends from the surface of the nuclear membrane.
171
Which of the following body cells have large amounts of ribosomes?
Muscle cell
*The muscle cells/tissues have a large number of ribosomes and, therefore, a higher rate of protein synthesis.
171
What is the main function of the rough endoplasmic reticulum?
Rough ER helps in protein synthesis required for the rest of the cellular function.
172
What is the main difference between the two types of endoplasmic reticulum?
The rough ER has ribosomes on its membrane surface whereas the smooth ER does not.
173
Which of the following is the function of the Golgi complex?
The Golgi complex helps in sorting the new proteins into the vesicles.
174
Which of these functions is performed by lysosomes?
Lysosomes carry out intracellular digestion and disintegrate the cell after its death.
175
Certain dead cells and foreign substances are normally removed from our cells with the help of cellular digestive enzymes. Which organelles contain these enzymes?
Lysosomes
176
Which of the following statements correctly describes the process of phagocytosis?
Phagocytosis is the process where the cell membrane invaginates to engulf foreign particles and forms a vacuole, within, to digest them.
177
Which of the following statements correctly describes mitochondria?
Mitochondria is responsible for cellular respiration in both plants and animals.
178
What is the main function of a flagellum?
A flagellum helps in the locomotion of the organism.
179
Which of the following functions are carried out by the cytoskeleton of the cell?
The cytoskeleton helps in cell division and cytokinesis.
180
What is the chief role of cholesterol in the cell membrane’s function?
It decreases the permeability of the cell membrane.
*Cholesterol gets deposited into the phospholipid layer and restricts the movement of the molecules across the cell membrane.
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A cell membrane acts as a semipermeable membrane. What does that mean?
It allows only certain molecules to diffuse across the membrane.
