Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology HL - IB > Cell specialisation > Flashcards

Cell specialisation Flashcards

(101 cards)

Start Studying
1
Q

What occurs immediately after fertilization in terms of cell production?

A

Following fertilization, a zygote is formed, which undergoes several rounds of cell division to produce unspecialized cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are unspecialized cells?

A

Unspecialized cells, also known as stem cells, have the potential to differentiate into various specialized cell types depending on developmental cues.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How does differentiation occur in early-stage embryos?

A

Differentiation occurs as cells respond to various signals and gradients, leading them to develop into specific cell types with distinct functions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the significance of gradients in early-stage embryos?

A

Gradients of signaling molecules (morphogens) influence gene expression patterns, guiding the differentiation process and determining cell fate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How do morphogens affect gene expression?

A

Morphogens create concentration gradients that activate or repress specific genes in target cells, leading to the formation of different tissues and organs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What role does the environment play in cell differentiation?

A

The cellular microenvironment, including neighboring cells and extracellular matrix components, provides signals that can influence the differentiation pathway of unspecialized cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why is the ability to differentiate important for multicellular organisms?

A

Differentiation allows for the development of specialized cells and tissues necessary for complex functions, enabling multicellular organisms to thrive and adapt.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does the process of differentiation relate to embryonic development?

A

During embryonic development, unspecialized cells progressively differentiate into specialized cell types that form the various tissues and organs of the organism.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What happens if differentiation processes are disrupted?

A

Disruption in differentiation can lead to developmental abnormalities, diseases, or failure to form necessary tissues and organs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Why is understanding cell differentiation significant in biology?

A

Understanding how unspecialized cells differentiate into specialized cells provides insights into development, regenerative medicine, and potential treatments for diseases related to cell function.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are stem cells?

A

Stem cells are unspecialized cells with the unique ability to divide indefinitely and differentiate into various specialized cell types.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the capacity of stem cells to divide?

A

Stem cells have the capacity to undergo endless divisions, allowing them to produce a large number of daughter cells while maintaining their own population.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do stem cells differentiate?

A

Stem cells can differentiate into specialized cells through specific signaling pathways and environmental cues that activate particular gene expression patterns.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the significance of differentiation in stem cells?

A

Differentiation allows stem cells to develop into various cell types necessary for the formation of tissues and organs, contributing to overall organism development.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What factors influence the differentiation of stem cells?

A
  1. Signaling Molecule Gradients
    Cells detect concentration differences of signaling proteins like BMP (bone morphogenetic proteins). Near the signaling source (e.g., in the stem cell niche), high BMP levels keep stem cells undifferentiated. As cells move away, lower BMP levels trigger differentiation. For example, BMP gradients help decide whether a stem cell becomes a skin cell or a neuron.
  2. Cell-Cell Interactions
    Direct contact between cells or chemical signals (like hormones) influence fate. For example:
    - Contact-dependent signals: Neighboring cells send proteins through gap junctions to activate differentiation genes.
    - Growth factors: Insulin released by pancreatic cells can guide nearby stem cells to become insulin-producing cells.
  3. Extracellular Matrix (ECM)
    The physical and chemical environment around cells provides cues:
    - Stiffness: A rigid ECM (like bone) promotes bone cell differentiation, while a soft ECM (like brain tissue) guides nerve cell development.
    - Anchor points: ECM proteins like collagen act as “handholds” that trigger internal signals when cells attach.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How do gradients affect stem cell behavior?

A

Gradients of morphogens create concentration differences that can activate or repress certain genes, guiding stem cell fate and promoting differentiation into specific lineages.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the four main types of stem cells?

A

Therearefourtypes ofpotency:
Totipotency
- Totipotent stem cells are stem cells that can differentiate into any cell type found in an embryo, as well as extra-embryonic cells (the cells that make up the placenta)
- The zygote formed when a sperm cell fertilises an egg cell is totipotent
- Also the embryonic cells up to the16-cell stage of human embryo development
are totipotent

Pluripotency:
- Pluripotent stem cells are embryonic stem cells that can differentiate
into any cell type found in an embryo but are not able to differentiate into extra-embryonic cells (the cells that make up the placenta)

Multipotency
- Multipotent stem cells are adult stem cells that can differntiation closely related cell types
- For example bone marrow stem cells differntiate

erentbloodcells

Unipotency - unipotent stem cells areadultcells thatcan onlydi

erentiateintotheir

own lineage
Forexampleheartmusclecells (cardiomyocytes) can generatenew
cardiomyocytes through thecellcycletobuildandreplaceheartmuscle. Most
cells in animalbodies areunipotent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Why is the ability to differentiate important for multicellular organisms?

A

The ability to differentiate allows multicellular organisms to develop specialized tissues and organs, enabling complex functions necessary for survival and adaptation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How does understanding stem cell properties contribute to medicine?

A

Understanding the properties of stem cells opens avenues for regenerative medicine, tissue engineering, and potential treatments for diseases caused by cell loss or dysfunction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What can happen if differentiation processes are disrupted in stem cells?

A

Disruption in differentiation can lead to developmental disorders, cancer (due to uncontrolled proliferation), or failure to produce necessary cell types for tissue function.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are stem cell niches?

A

Stem cell niches are specialized microenvironments within tissues that maintain stem cells and regulate their behavior, including proliferation and differentiation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Where is one location of a stem cell niche in adult humans?

A

One example of a stem cell niche is found in the bone marrow, which houses hematopoietic stem cells responsible for producing blood cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the function of the stem cell niche in the bone marrow?

A

The bone marrow niche provides signals and support to maintain hematopoietic stem cells and regulate their differentiation into various blood cell types.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Where is another location of a stem cell niche in adult humans?
Hair follicles contain a stem cell niche that contributes to hair growth and regeneration by providing a reservoir of epithelial stem cells.
26
How do hair follicle stem cells function within their niche?
Hair follicle stem cells receive signals from the surrounding environment that promote their proliferation and differentiation into hair shaft and other follicular cells.
27
What role does the microenvironment play in maintaining stem cells?
The microenvironment of a stem cell niche provides essential signals, including growth factors and extracellular matrix components, that influence stem cell fate decisions.
28
How can the stem cell niche promote proliferation?
The niche can promote proliferation by providing a supportive environment with necessary nutrients and signaling molecules that stimulate stem cell division.
29
How does the niche influence differentiation of stem cells?
The niche can direct differentiation by releasing specific signals or morphogens that activate particular gene expression pathways in stem cells.
30
Why is understanding stem cell niches important in medicine?
Understanding how stem cell niches function can lead to advancements in regenerative medicine, tissue engineering, and therapies for diseases involving stem cell dysfunction.
31
What happens if the balance within a stem cell niche is disrupted?
Disruption in the balance of signals within a stem cell niche can lead to inadequate maintenance of stem cells, resulting in impaired tissue regeneration or diseases such as cancer.
32
What are totipotent stem cells?
Totipotent stem cells are the most versatile type of stem cells, capable of developing into any cell type in the body, including both embryonic and extra-embryonic tissues.
33
When do cells become totipotent during development?
Cells are totipotent during the early stages of embryonic development, specifically from fertilization up to the eight-cell stage in mammals.
34
What are pluripotent stem cells?
Pluripotent stem cells can differentiate into nearly all cell types in the body but cannot form extra-embryonic tissues like the placenta.
35
When do cells transition from totipotent to pluripotent?
Cells transition to pluripotency after the early cleavage stages of development, typically around the blastocyst stage.
36
What are multipotent stem cells?
Multipotent stem cells have a more limited differentiation potential compared to pluripotent cells; they can develop into a restricted range of cell types within a specific tissue or organ.
37
Where are multipotent stem cells commonly found in adult humans?
Multipotent stem cells are found in various adult tissues, such as bone marrow (hematopoietic stem cells) and skin (epithelial stem cells).
38
How do the differentiation capabilities of totipotent, pluripotent, and multipotent stem cells differ?
Totipotent cells can form any cell type, pluripotent cells can form nearly all cell types except extra-embryonic tissues, and multipotent cells can only form specific cell types related to their tissue origin.
39
Why is it important to understand the differences between these types of stem cells?x
Understanding these differences is crucial for advancements in regenerative medicine, developmental biology, and therapeutic applications targeting specific cell types.
40
What happens if there is a failure in the differentiation process of stem cells?
A failure in differentiation can lead to developmental disorders, cancer (due to uncontrolled proliferation), or insufficient production of necessary cell types for tissue function.
41
How does the understanding of totipotency and pluripotency contribute to research?
Knowledge of these concepts aids researchers in exploring potential treatments for diseases and injuries by harnessing the regenerative capabilities of stem cells.
42
How does cell size vary in humans?
Cell size in humans varies widely, with different types of cells exhibiting distinct sizes based on their specialized functions, such as gametes, blood cells, and muscle fibers.
43
What are the sizes of male and female gametes?
Male gametes (sperm) are typically about 50 micrometers long, while female gametes (eggs) are much larger, approximately 100 micrometers in diameter.
44
What is the size range of red blood cells?
Red blood cells are approximately 6-8 micrometers in diameter, allowing them to efficiently transport oxygen throughout the body.
45
How do white blood cells compare in size to red blood cells?
White blood cells are generally larger than red blood cells, ranging from 10 to 20 micrometers in diameter, reflecting their role in immune response and defense.
46
What is the significance of neuron size?
Neurons can vary significantly in size, with some having long axons that can extend over a meter, allowing for rapid transmission of signals across long distances in the body.
47
How do striated muscle fibers differ in size from other cells?
Striated muscle fibers (skeletal muscle cells) can be quite large, often exceeding 30 centimeters in length and containing multiple nuclei, enabling coordinated contraction and force generation.
48
What is the relationship between cell size and function?
Cell size is often related to its specific function; larger cells may be specialized for tasks requiring more space or resources, while smaller cells can facilitate rapid transport and communication.
49
Why is it important for gametes to be different sizes?
The size difference between male and female gametes ensures successful fertilization, with the larger egg providing nutrients and support for early development.
50
How does the size of red blood cells enhance their function?
The biconcave shape and small size of red blood cells increase their surface area-to-volume ratio, optimizing oxygen diffusion and transport efficiency.
51
What role does understanding cell size play in biology?
Understanding cell size and specialization helps explain how different cell types contribute to overall organism function, development, and adaptation to various physiological demands.
52
What is the surface area-to-volume ratio?
The surface area-to-volume ratio is a mathematical relationship that compares the surface area of a cell to its volume, influencing how efficiently materials can be exchanged with the environment.
53
Why is the surface area important for cells?
The surface area determines the capacity for exchange of materials (such as nutrients and waste) across the cell membrane; larger surface areas facilitate more efficient exchange.
54
How does cell volume affect the need for exchange?
The volume of a cell reflects its metabolic activity and resource needs; larger volumes require more nutrients and produce more waste, increasing the demand for efficient exchange.
55
What happens to the surface area-to-volume ratio as a cell grows?
As a cell increases in size, its volume grows faster than its surface area, leading to a decrease in the surface area-to-volume ratio, which can limit the cell's ability to exchange materials effectively.
56
How can models help illustrate the surface area-to-volume relationship?
Models, such as cubes of different side lengths, can simplify the complex relationships in real organisms, allowing for easier understanding of how scale factors operate similarly in biological systems.
57
What is a consequence of having a low surface area-to-volume ratio in larger cells?
A low surface area-to-volume ratio can result in insufficient exchange of materials, potentially leading to nutrient shortages or accumulation of waste products, which can impair cellular function.
58
Why do smaller cells tend to have higher surface area-to-volume ratios?
Smaller cells have relatively larger surface areas compared to their volumes, enhancing their ability to efficiently absorb nutrients and expel waste.
59
How does cell specialization relate to size and surface area-to-volume ratios?
Specialized cells may adapt their shapes or structures (e.g., microvilli in intestinal cells) to maximize their surface area relative to volume, improving their efficiency in specific functions.
60
What is one adaptation that helps larger cells overcome size constraints?
Larger cells may develop specialized structures (such as folds or extensions) to increase their effective surface area without significantly increasing volume.
61
Why is understanding surface area-to-volume ratios important in biology?
Understanding these ratios is crucial for comprehending how cell size and shape influence metabolic functions, nutrient uptake, and overall cellular efficiency in living organisms.
62
Why is increasing the surface area-to-volume ratio important for cells?
Increasing the surface area-to-volume ratio enhances the efficiency of material exchange across the cell membrane, which is crucial for nutrient uptake and waste removal.
63
What is one adaptation that cells use to increase their surface area?
Flattening of cells increases surface area, allowing for more efficient exchange of materials without significantly increasing cell volume.
64
How do microvilli contribute to surface area?
Microvilli are tiny, finger-like projections on the surface of some cells that greatly increase the surface area available for absorption and exchange processes.
65
What is an example of a cell that utilizes microvilli?
Epithelial cells in the intestines have microvilli that enhance nutrient absorption by increasing the surface area in contact with digested food.
66
What is invagination in the context of cell structure?
Invagination refers to the inward folding of a cell membrane, which can create additional surface area for exchange processes while maintaining a compact cell volume.
67
How do erythrocytes (red blood cells) exemplify adaptations for increased surface area-to-volume ratios?
Erythrocytes have a biconcave shape that increases their surface area relative to volume, facilitating efficient gas exchange (oxygen and carbon dioxide) in the bloodstream.
68
What role do proximal convoluted tubule cells in the nephron play in increasing surface area?
Proximal convoluted tubule cells have numerous microvilli that enhance their ability to reabsorb water, ions, and nutrients from filtrate back into the bloodstream.
69
Why is it beneficial for proximal convoluted tubule cells to have a high surface area-to-volume ratio?
A high surface area-to-volume ratio allows these cells to maximize reabsorption efficiency, ensuring essential substances are retained while waste products are excreted.
70
How does understanding adaptations to increase surface area-to-volume ratios contribute to biology?
Understanding these adaptations helps explain how different cell types optimize their functions and maintain homeostasis within larger biological systems.
71
What can happen if a cell's surface area-to-volume ratio becomes too low?
If a cell's surface area-to-volume ratio is too low, it may struggle to efficiently exchange materials, leading to metabolic inefficiencies and potential cell dysfunction or death.
72
What are type I pneumocytes?
Type I pneumocytes are thin, flat epithelial cells that line the alveoli in the lungs and facilitate gas exchange by providing a minimal barrier for diffusion.
73
How does the extreme thinness of type I pneumocytes benefit gas exchange?
The extreme thinness reduces the distance for diffusion of oxygen and carbon dioxide, allowing for efficient gas exchange between the alveoli and bloodstream.
74
What are type II pneumocytes?
Type II pneumocytes are cuboidal epithelial cells in the alveoli that produce and secrete pulmonary surfactant, which reduces surface tension in the alveoli.
75
What are lamellar bodies in type II pneumocytes?
Lamellar bodies are specialized secretory vesicles within type II pneumocytes that store surfactant until it is released into the alveolar lumen.
76
How does surfactant produced by type II pneumocytes function?
Surfactant reduces surface tension within the alveoli, preventing collapse during exhalation and improving lung compliance, making breathing easier.
77
Why is it important for both type I and type II pneumocytes to be present in the alveoli?
The presence of both cell types allows for efficient gas exchange (type I) while maintaining lung stability and function through surfactant production (type II).
78
How do adaptations of type I and type II pneumocytes illustrate specialization in tissue function?
These adaptations demonstrate how different cell types within a tissue can have specific roles that contribute to the overall function of the organ—in this case, efficient respiration.
79
What is the overall role of the alveolar epithelium in the respiratory system?
The alveolar epithelium facilitates gas exchange between air in the lungs and blood in capillaries while maintaining proper lung function through structural support and surfactant production.
80
How does understanding the adaptations of pneumocytes contribute to medical science?
Understanding these adaptations can inform treatments for respiratory conditions, such as surfactant replacement therapy for premature infants with respiratory distress syndrome.
81
What could happen if type II pneumocytes fail to produce sufficient surfactant?
Insufficient surfactant production can lead to increased surface tension, alveolar collapse (atelectasis), impaired gas exchange, and respiratory distress.
82
What are the main features of cardiac muscle cells?
Cardiac muscle cells are branched, striated, and interconnected, allowing for coordinated contractions essential for pumping blood.
83
How do the lengths and nuclei of cardiac muscle cells differ from striated muscle fibers?
Cardiac muscle cells typically have one or two nuclei and are shorter than striated muscle fibers, which are long, cylindrical, and multinucleated.
84
What is the significance of branching in cardiac muscle cells?
The branching structure allows for efficient electrical conduction and synchronization of contractions across the heart, ensuring effective blood pumping.
85
What are striated muscle fibers?
Striated muscle fibers, also known as skeletal muscle fibers, are long, cylindrical cells characterized by a regular arrangement of myofibrils, giving them a striped appearance.
86
How do contractile myofibrils function in both cardiac and striated muscle cells?
Contractile myofibrils contain actin and myosin filaments that interact to produce muscle contraction through the sliding filament mechanism.
87
Why do striated muscle fibers have multiple nuclei?
The presence of multiple nuclei in striated muscle fibers allows for the coordination of metabolic activities and protein synthesis necessary for maintaining large cell size and function.
88
What hypothesis explains the differences between cardiac and striated muscle cells?
The differences in structure (branching vs. unbranched) and number of nuclei may relate to their distinct functional roles; cardiac muscles require synchronized contractions while skeletal muscles need to exert force over a wide range of motion.
89
How does the structure of cardiac muscle cells support their function?
The intercalated discs between cardiac cells facilitate rapid communication and coordination, allowing the heart to contract as a unified organ.
90
Are striated muscle fibers considered individual cells?
Yes, striated muscle fibers are considered individual cells despite being multinucleated; they form through the fusion of myoblasts during development.
91
Why is understanding the adaptations of cardiac and striated muscle important in biology?
Understanding these adaptations helps explain how different types of muscle tissue meet specific physiological demands, contributing to overall organism function and health.
92
What are the primary functions of sperm and egg cells in humans?
Sperm cells are responsible for fertilizing the egg, while egg cells (ova) provide the genetic material and nutrients necessary for early embryonic development.
93
What adaptations do sperm cells have for their function?
Sperm cells are streamlined and have a flagellum (tail) that allows for efficient swimming towards the egg, maximizing their chances of successful fertilization.
94
How does the structure of sperm contribute to its motility?
The elongated shape and presence of a flagellum reduce resistance in the fluid environment, enabling rapid movement through the female reproductive tract.
95
What is the role of the acrosome in sperm cells?
The acrosome is a cap-like structure that contains enzymes necessary for penetrating the protective layers surrounding the egg during fertilization.
96
What adaptations do egg cells have for their function?
Egg cells are larger than sperm and contain substantial cytoplasm, which provides nutrients and support for the developing embryo after fertilization.
97
How does the size of an egg cell benefit embryonic development?
The large size of the egg cell allows it to store essential nutrients and organelles needed for early cell divisions and growth before implantation.
98
What is the significance of the zona pellucida in egg cells?
The zona pellucida is a protective glycoprotein layer surrounding the egg that facilitates sperm binding and prevents multiple sperm from fertilizing the same egg.
99
How do sperm and egg cells exemplify specialization in gametes?
Sperm are specialized for mobility and delivery of genetic material, while eggs are specialized for nurturing early development, reflecting their distinct roles in reproduction.
100
Why is it important for sperm to reach the egg efficiently?
Efficient movement towards the egg increases the likelihood of fertilization, which is essential for successful reproduction and continuation of genetic material.
101
How does understanding the adaptations of sperm and egg cells contribute to reproductive biology?
Understanding these adaptations provides insights into fertility, reproductive health, and potential treatments for infertility issues in humans.

Biology HL - IB (35 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions