Cell Structure & Function Flashcards

Learn the characteristics of living things and identify structures in prokaryotic and eukaryotic cells, explaining how each part contributes to cell function. (160 cards)

1
Q

What is the cell theory?

A
  • Everything living is made of cells.
  • The smallest structural component of everything living is the cell.
  • Existing living cells create new cells.
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2
Q

After hearing about Schleiden’s discoveries with plant cells, what did Theodor Schwann discover in 1839 about animals and cells?

A

That animals are comprised of cells.

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3
Q

What did Matthias Schleiden discover about plants and cells in 1838?

A

That plants are comprised of cells.

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4
Q

What was Rudolf Virchow’s contribution to classical cell theory?

A

He proposed the third and final tenet that all living cells must come from other living cells.

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5
Q

What additional concepts does modern cell theory add to classical cell theory?

A
  • Chemical energy flows within cells. (metabolism)
  • Genetic material is transferred to new cells during cellular division. (DNA)
  • All cells are chemically and structurally similar.
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6
Q

What did the cell theory put an end to?

A

The debate about spontaneous generation.

The cell theory rejected the idea that cells appeared ‘out of thin air’.

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7
Q

Who discovered and described unicellular bacteria and protists.

A

Antonie van Leeuwenhoek

He discovered and described unicellular bacteria using early microscopes, marking the first observation of single-celled organisms.

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8
Q

Where does chlorophyll exist in plant cells?

A

Within the thylakoid membranes of plant chloroplasts.

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9
Q

What process converts chemical energy from sunlight into glucose and oxygen in plant cells?

A

Photosynthesis

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10
Q

What is cleavage in the context of animal development?

A

The process by which the zygote rapidly divides without growing to become multicellular.

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11
Q

What are the three primary germ layers in animal development?

A
  • Ectoderm
  • Mesoderm
  • Endoderm
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12
Q

What is the cell wall in plant cells composed of?

A

Cellulose

The cell wall is primarily made up of this carbohydrate. It is composed mainly of cellulose, which provides structural support and protection.

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13
Q

What type of cell arrangement is typical for prokaryotes?

A

Single-celled organisms.

Example: Bacteria, Archaea

Bacteria typically exhibit simple arrangements such as chains (strepto-) or clusters (staphylo-), depending on how they divide.

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14
Q

What type of cell arrangement is typical for eukaryotes?

A

Can be single-cellular or multicellular organisms.

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15
Q

How do prokaryotes and eukaryotes differ in terms of reproduction?

A
  • Prokaryotes reproduce asexually.
  • Eukaryotes are able to reproduce sexually.
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16
Q

What are the differences in organelles between plant and animal cells?

A
  • Plant Cells:
    • Rectangular shape
    • One large central vacuole
    • No lysosomes
    • Chloroplasts present
    • Cell wall present
    • Does not contain centrosomes to aid in replication.
  • Animal Cells:
    • Round shape
    • Several small vacuoles
    • Lysosomes present
    • No chloroplasts
    • No cell wall
    • Contains centrosomes to aid in replication.
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17
Q

What is the function of chloroplasts in a plant cell?

A

The site where photosynthesis occurs.

Responsible for photosynthesis by converting water and carbon dioxide into food for the plant.

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18
Q

What is a key difference between plant cells and animal cells?

A

Plant cells have cell walls, chloroplasts and central vacuoles. Animal cells do not.

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19
Q

List the similarities between animal cells and plant cells.

A
  • Eukaryotic cells
  • surrounded by a cell membrane
  • contain membrane-bound organelles
  • mitochondria
  • nucleus
  • Golgi Apparatus
  • Endoplasmic reticulum
  • ribosomes
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20
Q

What are some similarities between bacterial cells and eukaryotic cells?

A
  • Cell wall (in some cases)
  • Cell membrane
  • Ribosomes
  • Cytoplasm
  • Genetic material
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21
Q

What is a key feature unique to plant cells?

A

Presence of a cell wall for support and rigidity.

The cell wall surrounds the membrane of a plant cell.

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22
Q

What is the main difference in nutrition between plant cells and animal cells?

A
  • Plant cells are autotrophs.
  • Animal cells are heterotrophs.
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23
Q

What is the prominent structure found in plant cells that occupies a large portion of the cell volume and stores water?

A

Large central vacuole

The vacuole helps the cell elongate as well as help with water balance within the cell and perform photosynthesis.

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24
Q

What structure found in animal cells acts as a microtubule organizing center during cell division?

A

centrosome

The centrosome contains a pair of centrioles at right angles to each other.

The centrosome in animal cells acts as the main microtubule organizing center, playing a key role in cell division.

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25
What is the function of vacuoles in both plant and animal cells?
Used as temporary storage sites for food, enzymes, water and other materials.
26
What organelles in **plant** and **animal** cells provide energy?
* Animal cell: **Mitochondria** * Plant cell: **Chloroplasts** ## Footnote Mitochondria exist in both plant and animal cells.
27
What is the *structure* of **chloroplasts** in plant cells?
* Double membrane. * Stacks of sacks known as grana.
28
What is the **cytoskeleton** in both plant and animal cells?
A network of protein filaments that help provide structure and support for the cell.
29
Do prokaryotic cells have a **true membrane-bound nucleus**?
No ## Footnote Prokaryotic cells lack a true membrane-bound nucleus; instead, their DNA is located in a region called the nucleoid.
30
How do prokaryotic and eukaryotic ribosomes **differ**?
They are both made of rRNA and proteins, but the subunits are **different sizes**. ## Footnote Eukaryotic ribosomes are bigger than prokaryotic ribosomes.
31
What is the function of **ribosomes** in a cell?
Ribosomes translate mRNA into proteins used for cell growth, repair, and function.
32
What is the **endoplasmic reticulum (ER)** referred to as in the cell?
The **transport system** or highway of the cell.
33
What are the **two categories** of endoplasmic reticulum (ER)?
* Smooth ER (SER) * Rough ER (RER)
34
What is the **rough endoplasmic reticulum (RER)** responsible for?
Transporting properly synthesized proteins and **retaining** incorrectly made proteins.
35
What is the **smooth endoplasmic reticulum (SER)** responsible for?
Synthesizing, transporting, and storing lipids needed by the cell.
36
What is the function of the **Golgi apparatus**?
To further process and package materials into secretory vesicles for transport. ## Footnote Often referred to as the post office of the cell.
37
What is the function of the **nucleus** in a cell?
Contains a cell's **genetic code** which provides the instructions for protein synthesis.
38
What is the **rough endoplasmic reticulum**?
Endoplasmic reticulum with membrane-bound ribosomes attached.
39
What is the function of **lysosomes** in a cell?
Contain digestive enzymes to **break down** excess or worn out organelles, food particles, viruses, and bacteria.
40
What is the **function** of **mitochondria** in a cell?
Transform energy and break down stored energy. ## Footnote Often referred to as the powerhouse of the cell.
41
What is a **ribosome**'s structure?
A cellular organelle made up of **multiple proteins and ribosomal RNA**. It contains two subunits, one large and one small, that join together during the translational process.
42
What happens to proteins synthesized by **membrane-bound ribosomes**?
They are transferred to the endoplasmic reticulum, then to the Golgi apparatus for processing.
43
What is the function of the **smaller subunits** of ribosomes?
Decoding the messenger RNA.
44
What is the function of the **larger subunits** of ribosomes?
Formation of the peptide bonds.
45
What are the **stages** of protein synthesis in ribosomes?
1. Initiation stage 2. Elongation stage 3. Termination stage
46
Where can ribosomes be found within the cell?
* Free in the cytoplasm. * Bound to the endoplasmic reticulum. * Within the mitochondria and chloroplasts.
47
What is **homeostasis**?
Regulation of an organism's internal environment.
48
What are the **three main systems** of homeostasis in body systems?
* Thermoregulation * Osmoregulation * Chemical regulation
49
What are the main components of body systems for maintaining homeostasis?
* Sensor/Receptor * Control center * Effector ## Footnote **Sensor/Receptor**- Nervous System detects a change. **Control center**- Brain determines how to respond. **Effector**- organs carry out orders from the brain and returns the body to homeostasis. Example: The nerves in your skin detect the cold and send signals to your brain. The brain then directs nearby blood vessels to constrict, reducing blood flow near the skin’s surface to conserve heat.
50
What are the two main types of **feedback loops** in maintaining homeostasis?
* Positive feedback loops * Negative feedback loops
51
Which **body systems** are involved in homeostasis?
**All** body systems. ## Footnote Homeostasis involves coordination of multiple systems, including the nervous, endocrine, respiratory, and circulatory systems.
52
What is the main purpose of the **plasma membrane** in both prokaryotic and eukaryotic cells?
It is a thin, flexible, selectively permeable barrier that **protects** the cell and **regulates** the passage of substances in and out.
53
What is the function of the **nuclear membrane** in eukaryotic cells?
**Regulates transport** into and out of the nucleus and keeps the DNA safe.
54
What is a **plasma membrane**?
Also known as the cell membrane, is the thin, flexible barrier that **separates** the cell from the environment.
55
What does the **plasma membrane** do?
Has several important functions including: * Protection * Transport * Recognition * Cell signaling
56
What does the plasma membrane allow to **diffuse** directly across it?
Small, nonpolar molecules, such as oxygen and carbon dioxide.
57
How do larger molecules like glucose **move** across the plasma membrane?
They require **transport proteins** to move across the plasma membrane.
58
What is the role of the plasma membrane in **cell signaling**?
Molecules attach to receptors on the surface of the cell membrane **transporting signals** between cells.
59
What are the components of the **plasma membrane**?
* Phospholipid Bilayer * Proteins * Carbohydrates * Cholesterol
60
What is the **main function of carbohydrates** in the plasma membrane?
Cell recognition ## Footnote Carbohydrates in cells primarily provide energy storage (as starch or glycogen) and structural support (as cellulose or chitin).
61
Are phospholipids **stationary** in the plasma membrane?
Lateral movement, rotation, and sometimes **translocation** can occur within the cell membrane.
62
What type of **proteins** are found in the plasma membrane?
* Peripheral proteins * Integral proteins ## Footnote Peripheral proteins only go halfway through the membrane. Integral proteins go entirely through the membrane.
63
What **stabilizes** the phospholipids in the plasma membrane?
cholesterol molecules ## Footnote Cholesterol molecules located throughout the surface of the plasma membrane help stabilize the phospholipids and keep them in position ensuring membrane fluidity.
64
What are **membrane-bound organelles?**
Organelles surrounded by a **phospholipid bilayer**.
65
What is the **main function** of a membrane-bound organelle?
Isolate certain chemical reactions and processes while regulating what substances enter and leave the organelle.
66
What **types of cells** have membrane bound organelles?
Eukaryotic cells ## Footnote Examples: nucleus, mitochondria, and endoplasmic reticulum, unlike prokaryotes.
67
Which organelles are membrane-bound?
* Endoplasmic reticulum (both the smooth and the rough) * Golgi apparatus * Vacuoles * Mitochondria * Lysosomes (found in animal cells) * Chloroplasts (found in plant cells) ## Footnote Other organelles, that are not membrane bound include ribosomes, peroxisomes, cilia, flagella, centrioles, microtubules, cytoskeleton, centrosomes, and the cell wall.
68
What is a **membrane-bound** cell?
A **cell surrounded by a phospholipid bilayer** known as the plasma membrane. ## Footnote The plasma membrane also separates the internal components of a cell and the environment.
69
Who coined the term **'cell'** and described cells in detail in 1665?
Robert Hooke ## Footnote Hooke named them cells because when he examined a piece of cork under the microscope he noticed little structures that reminded him of the living quarters of monks- *also known as cells.*
70
Who studied **cellular division** in frog embryos in the 1850s?
Robert Remak
71
Which scientist **identified chromosomes and mitosis** in salamander cells in the 1880s?
Walther Flemming
72
Who described how cells **pass down chromosomes** (DNA) during division?
August Weismann
73
What is the main function of **chlorophyll** in photosynthesis?
Absorbing specific wavelengths of light energy. ## Footnote Chlorophyll absorbs red and blue wavelengths of light to fuel photosynthesis.
74
What is the **chemical equation** for photosynthesis?
6CO2 + 6H2O → C6H12O6 + 6O2 ## Footnote CO2= carbon dioxide H2O= water C6H12O6= glucose O2= oxygen
75
What wavelengths of **visible light** does chlorophyll mostly absorb?
* Blue * Red ## Footnote Green wavelengths are reflected, which is why plants appear green.
76
How do **electrons** in chlorophyll behave when they absorb light energy?
They jump to a **high energy level**, or excited state.
77
# Fill in the blanks: **Photosynthesis** is essentially the reverse of \_\_\_\_\_\_ \_\_\_\_\_\_.
cellular respiration
78
What is a **living organism**?
Anything that exhibits all of the characteristics of **life**. ## Footnote Examples: Humans, fungi, algae, trees, animals, bacterial, protozoa, insects.
79
What are the common **characteristics of living organisms**?
* Cellular organization * Reproduction * Growth and development * Regulation * Respond to stimuli * Use and obtain nutrition * Excretion of waste
80
What is **cellular organization** in living organisms?
It ranges from atoms and molecules to cells, tissues, organs, organ systems, and the entire organism.
81
What are the **two types of cells** that comprise living organisms?
* **Eukaryotic cells** (organelles are surrounded by a membrane) * **Prokaryotic cells** (organelles not surrounded by a membrane)
82
What is **reproduction** in living organisms?
The process of **producing new individuals**. ## Footnote Reproduction can be sexual (requiring a partner), or asexual (not requiring a partner).
83
How do living organisms **obtain energy**?
From **metabolism** of food and **cellular respiration**. ## Footnote The sun is the ultimate source of energy in an ecosystem. Producers convert sunlight to a usable form that is able to be consumed by other living organisms.
84
What is the **response to stimuli** in living organisms?
The ability to **detect and respond** to physical or chemical changes in the internal or external environment. ## Footnote Example: Venus flytrap snapping shut quickly when a fly lands on it.
85
What is the **role** of regulation in living organisms?
The ability to **regulate internal functions** in response to external stimuli.
86
What is the term for the specific characteristics that living organisms develop to **thrive in their environment**?
Adaptations ## Footnote Heritable traits or features that improve an organism’s survival and reproductive success in a particular environment.
87
What is the term for the process by which living organisms obtain energy by **breaking down food**?
Cellular respiration
88
Living organisms can either be **unicellular** or **multicellular**. What is the basic unit of organization in living organisms?
Cells
89
What are the **two ways** in which offspring are produced in living organisms?
* Sexual reproduction * Asexual reproduction
90
What is the term for the change from a **small size to a larger size** in living organisms?
Growth ## Footnote For example, a seedling growing into a mature plant demonstrates biological growth.
91
What is the term for the **change in features and characteristics** throughout the life of an organism?
Development ## Footnote For instance, a caterpillar transforming into a butterfly illustrates development.
92
What are **autotrophs**?
Organisms that can produce their own food. ## Footnote Auto means self.
93
What are **heterotrophs**?
Organisms that must eat **other** organisms to get energy and nutrition. ## Footnote Hetero means other. Examples: Insect, birds, humans
94
What is **evolutionary adaptation**?
Living things are descendants of their ancestors and adapt to their environments over long periods of time.
95
Differentiate between sexual and asexual reproduction.
* **Sexual reproduction** involves the fusion of gametes, resulting in genetic diversity. * **Asexual reproduction** involves a single parent and produces genetically identical offspring.
96
# Define: thermoregulation
The process of regulating body **temperature**.
97
# Define: osmoregulation
The maintenance of the body's **salt and water balance** in homeostasis.
98
# Define: chemical regulation
The process of maintaining **homeostasis of chemicals** in the body.
99
What occurs in a **positive feedback loop**?
The product of the effector stimulates the effector and **increases the product**. ## Footnote Example: A woman is pregnant and nearing birth. The body will release oxytocin leading to increased uterine contractions. As the contractions continue more oxytocin is released leading to the continuation and amplification of labor until the baby is born. Once the baby is born the high level of oxytocin being released stops.
100
What occurs in a **negative feedback loop**?
The original state is **restored** due to a response that **opposes** that change. ## Footnote Example: Your body senses that as you are working out the concentration of oxygen in your blood is low. In response you begin breathing heavily and your heart beats more rapidly. Your body will continue to behave this way until you slow down your exercise and your oxygen levels return to normal. Once homeostasis has been achieved your breathing and heart rate will also return to their normal level.
101
How does the hypothalamus regulate **body temperature**?
By **processing sensory information** and causing changes in effector organs, such as sweating and dilating blood vessels to release excess heat.
102
How are **blood glucose levels** controlled?
By the **pancreas secreting insulin** when levels are high and glucagon when levels are low.
103
What is **diabetes**?
A condition where **dysfunction of glucose homeostasis** causes blood glucose levels to be too high. ## Footnote Normal blood glucose levels: 100mg/dL (fasting) and no more than 140 mg/dL 2 hours after eating.
104
# Define: endocrine system
Body system that uses **hormones** that travel through the blood to convey messages.
105
What is the **hypothalamus** and what is its function?
Portion of the brain that controls the **endocrine system** and helps maintain **homeostasis** in the body.
106
What are **gametes**?
Specialized **sex cells** produced by each parent for sexual reproduction. ## Footnote Male Gamete: sperm Female Gamete: ova
107
What is **spermatogenesis**?
The process of creating **male gametes** (sperm).
108
What is **oogenesis**?
The process of creating **female gametes** (ova).
109
What is a **zygote**?
A fertilized ovum. ## Footnote It is the fertilized egg formed by the union of sperm and ovum, representing the first cell of a new organism.
110
What are the **three major body axes** that the zygote must establish after fertilization?
* Anteroposterior axis (head to tail) * Dorsoventral axis (back to belly) * Transverse axis (left to right)
111
What is the process of the **formation of organs** in the embryo called?
Organogenesis ## Footnote The stage of embryonic development in which the three germ layers (ectoderm, mesoderm, and endoderm) differentiate and give rise to the body’s organs and organ systems.
112
What is the purpose of an **energy pyramid**?
To show how energy is transferred within the **trophic levels**.
113
What **percentage** of energy is transferred from one trophic level to the next?
10% ## Footnote The other 90% of energy is heat lost due to metabolic processes.
114
What is the **genetic material** found in both prokaryotic and eukaryotic cells?
DNA ## Footnote The molecule that stores hereditary information in the form of genes. In prokaryotes, DNA is typically a single circular chromosome located in the nucleoid, while in eukaryotes, DNA is arranged into multiple linear chromosomes housed within the nucleus.
115
What is the **average size range** of prokaryotic cells?
**0.1 - 5 micrometers** in diameter.
116
What is the **average size range** of eukaryotic cells?
**10 - 100 micrometers** in diameter. ## Footnote Some eukaryotic cells are able to be seen with the naked eye, for example chicken egg.
117
How is **DNA structured** in prokaryotic cells compared to eukaryotic cells?
* Prokaryotic cells have DNA in a **single circular chromosome**. * Eukaryotic cells have DNA arranged into **linear chromosomes**.
118
What is the process of **cell division in eukaryotic cells** called?
Mitosis ## Footnote Eukaryotic cells divide by mitosis for growth and repair, and by meiosis to produce gametes for reproduction.
119
How do prokaryotic cells **divide**?
Using **binary fission**. ## Footnote Prokaryotic cells divide by binary fission, a simpler process than mitosis, producing two identical daughter cells.
120
What is the **main difference** between eukaryotic and prokaryotic cells?
Eukaryotic cells contain membrane-bound organelles, while prokaryotic cells do not.
121
What are some **examples** of eukaryotic organisms?
* Plants * Animals * Fungi
122
What is the **main advantage of organelles** in eukaryotic cells?
They **compartmentalize cellular functions**, separating processes and organizing space.
123
List the **similarities** between prokaryotic and eukaryotic cells.
* both are alive * have a cell membrane * contain DNA * have ribosomes * can divide and reproduce
124
Where does **DNA replication and transcription** take place in prokaryotic cells?
In the **nucleoid** area of the cytoplasm.
125
What specialized molecule makes up the **cell walls** of **prokaryotic cells**?
**Peptidoglycan** in most bacteria. ## Footnote A polymer of sugar and amino acids.
126
What is the function of **flagella** in prokaryotic and eukaryotic cells?
It enables **motility** and allow the cell to **move toward nutrients** or away from harmful conditions.
127
Where is the **DNA located** in prokaryotic cells?
In a space called the **nucleoid**. ## Footnote In prokaryotic cells, the DNA is circular and resides in the nucleoid.
128
What are the **main functions** of a cell?
* Structure and support. * Growth and repair. * Transport of materials. * Produce energy. * Reproduction.
129
What are the **differences** between prokaryotic and eukaryotic cells?
* Prokaryotic Cells: * Simple structure * Lack true nucleus * Lack membrane-bound organelles * Unicellular * Reproduce through binary fission * Eukaryotic Cells: * Larger and more complex * Contain diverse organelles * Have a membrane-bound nucleus * Can be multicellular * Reproduce through mitosis
130
What is a **simplified** description of prokaryotic cells?
Simple in structure and do not contain many organelles.
131
What **process** involves moving molecules into the cell through vesicles?
Endocytosis
132
What are the **hydrophilic** parts of phospholipids in the bilayer?
heads ## Footnote The hydrophilic heads of phospholipids face outward toward water, interacting with the aqueous environment.
133
What are the **hydrophobic** parts of phospholipids in the bilayer?
tails ## Footnote The hydrophobic fatty acid tails of phospholipids face inward, away from water, forming the interior of the bilayer.
134
What is the **fluid mosaic model** used to describe?
The **structure** of the plasma membrane. ## Footnote The fluid mosaic model describes the structure of the plasma membrane as fluid due to the drifting nature of its components and mosaic due to the various macromolecules that make it up.
135
What are **organelles**?
Small structures that perform different jobs within a cell.
136
Describe the structure of a **phospholipid bilayer**.
Consists of **two layers of phospholipids** with a hydrophilic phosphate head attracted to water and a hydrophobic lipid tail that does not interact with water.
137
What **provides the energy** required for **cellular processes** within a cell?
**ATP** created through cellular respiration within the **mitochondria**.
138
What are **cilia** and **flagella** made of?
Microtubules
139
What is the function of **intermediate filaments**?
Anchoring organelles in place within the cell and helping anchor the cell to the environment.
140
What are **microfilaments** made of?
The protein actin twisted together to form a long chain.
141
What are the **differences** between microtubules and microfilaments?
* **Microtubules**: * made of tubulin * have a diameter of 25 nm * involved in intracellular transport * **Microfilaments**: * made of actin * have a diameter of 7 nm * responsible for cellular movement
142
What are **intermediate filaments** made of?
Several fibrous proteins twisted together like twine.
143
What is the *function* of **microfilaments**?
* Keep cell shape. * Play a crucial role in muscle cell contraction. * Cause cell movement.
144
What is the function of **microtubules**?
* To provide support for the cell. * Aid in cell division. * Provide a route for intracellular transport.
145
What elements create the cytoskeletal structure?
* **Microfilaments**: made of the protein actin. * **Intermediate filaments**: made of a variety of proteins including keratin. * **Microtubules**: made of tubulin.
146
What is the **extracellular matrix**?
A complex structure of macromolecules that **keep cells together to form tissues** in the body.
147
What are the functions of the **extracellular matrix**?
* Contains growth factors. * Helps control when new blood vessels should form. * Serves as a guide for cell movement within the tissue. * Helps create stem cells leading to the development of specialized cells.
148
What is a **proteoglycan** composed of?
A protein core surrounded by long chains of starch-like molecules called glycosaminoglycans.
149
What type of cells are responsible for **producing and organizing** the components of the **extracellular matrix** in most tissues?
Fibroblasts ## Footnote They play a key role in wound healing by producing scar tissue and maintaining the structural framework of most tissues.
150
What is the function of **fibrous proteins** in the extracellular matrix?
Provide tensile strength and *support* to tissues.
151
What is the function of **proteoglycans** in the extracellular matrix?
Provide resistance to compressive forces.
152
Name the **four principle classes** of fibrous proteins found in the extracellular matrix.
* Collagen * Elastin * Fibronectin * Laminin ## Footnote Collagen is the most abundant protein in the human body.
153
What is the main function of **laminin** in the extracellular matrix?
Serves as the 'glue' between dissimilar tissues.
154
What is the main function of **fibronectin** in the extracellular matrix?
Helps position cells within the extracellular matrix, assist in cellular division and specialization.
155
What are the **components** of the extracellular matrix?
* Fibroblast cells * Proteoglycan proteins * Proteins such as collagen, laminin, fibronectin, and elastin
156
What term is used to describe organisms that can **create their own food**?
Autotroph
157
What term is used to describe organisms that **obtain food by consuming other organisms**, rather than producing their own.?
Heterotroph
158
What occurs during the **initiation stage** of ribosomal protein production?
**mRNA** binding to the smaller subunit of the ribosome and involves the **release of initiation factors**.
159
What occurs during the **elongation** stage of ribosomal protein production?
**GTP** binds with elongation factor Ef-Tu and **formation of peptide bonds** between amino acids.
160
What occurs during the **termination** stage of ribosomal protein production?
Recognition of termination codon by release factors **RF1 and RF2**, leading to the r**elease of the peptide chain**.