Michael Levin Bioelectricity 101 Crash Course Lesson 25: Bioelectric Circuits: The Body’s Control System for Shape Summary

• Bioelectric circuits are networks of cells that communicate and coordinate their activity through electrical signals.
• These circuits are not limited to the nervous system; they exist in all tissues.
• The key components of bioelectric circuits include ion channels, gap junctions, and the membrane potential of individual cells.
• These circuits are dynamic and reprogrammable; their activity patterns can change over time and in response to signals.
• Bioelectric circuits process information about the desired shape and structure of the organism (the “target morphology”).
• They control cell behaviors like proliferation, differentiation, migration, and apoptosis to achieve and maintain that shape.
• Bioelectric circuits are analogous to electronic circuits, but they use ions instead of electrons, and they are embedded within living tissue.
• Bioelectrical states are emergent properties: no single component (single ion channel, single cell, etc) “has” the “correct voltage” or any kind of anatomical setpoint. Rather, it is the interaction and dynamics that will generate those voltage landscapes we talked about previously.
• Disruptions in bioelectric circuits can lead to developmental defects, regeneration failures, and cancer.
• Understanding and manipulating bioelectric circuits offers exciting possibilities for regenerative medicine, cancer therapy, and synthetic bioengineering.
• Unlike genetic components, the activity across an electrical network is rapid.
• Gap junctions, when open, result in a lowering of the total membrane potential; when blocked, it raises.
• Bioelectricity is a good candidate for error correction of morphology, since it occurs over whole fields of tissues; it can help explain regenerative feats, and top-down control of biological outcomes.
• It helps link molecular biology with tissue scale organization (that had been an area of relative neglect.)

Michael Levin Bioelectricity 101 Crash Course Lesson 25: Bioelectric Circuits: The Body’s Control System for Shape

We’ve come a long way in this course! We’ve learned about ions, ion channels, membrane potential, voltage gradients, and how these electrical phenomena are not just confined to the nervous system but are fundamental to all cells. We’ve seen how bioelectric signals play crucial roles in development, regeneration, and even cancer. Now, it’s time to put all these pieces together and understand how these individual components work together as a system – a bioelectric circuit.

Think about an electronic circuit, like the one inside your phone or computer. It has various components (resistors, capacitors, transistors, etc.) connected in a specific way. These components interact with each other, processing electrical signals and controlling the device’s behavior. A bioelectric circuit is similar, but instead of using electrons flowing through wires, it uses ions flowing through ion channels and gap junctions. And instead of being built on a circuit board, it’s embedded within living tissue.

Here’s a breakdown of the key components of a bioelectric circuit:

• Ion Channels: These are the “gates” that control the flow of ions across the cell membrane. Different types of ion channels allow different types of ions to pass through, and they can be opened or closed in response to various signals (like voltage changes, chemical signals, or mechanical forces).
• Gap Junctions: These are direct connections between adjacent cells, forming channels that allow ions and small molecules to flow directly from one cell to another. Gap junctions create electrical coupling between cells, allowing them to share electrical signals and coordinate their activity. Think of them as “bridges” or “tunnels” connecting neighboring cells.
• Membrane Potential (Vmem): Each cell has a voltage difference across its membrane – the membrane potential. This voltage is created by the unequal distribution of ions inside and outside the cell. The membrane potential is a key variable in bioelectric circuits; changes in Vmem can act as signals, influencing cell behavior.
• The Cells Themselves: All of cells themselves in the tissue involved are connected by, or can sense bioelectric communication (like by an electrical field). This could also be likened to a collection of transistors on a circult board.

These components are not static; they are dynamic and interconnected. The activity of ion channels affects the membrane potential, which in turn can influence the opening or closing of gap junctions, and vice versa. This creates a complex network of feedback loops and interactions. And crucially, this network can change over time – it’s reprogrammable.

What does it mean to say that a bioelectric circuit is “reprogrammable”? It means that the pattern of electrical activity within the circuit can be altered, and this alteration can change the behavior of the cells within the circuit. It’s like rewriting the software of a computer – you can change the instructions without changing the physical hardware.

How does this “reprogramming” happen? It can occur through:

• Changes in ion channel expression: The cell can produce more or fewer of specific types of ion channels, changing the flow of ions and thus the membrane potential.
• Changes in ion channel activity: Existing ion channels can be opened, closed, or modified, altering their permeability to ions.
• Changes in gap junction connectivity: The number and strength of gap junctions between cells can be altered, changing the degree of electrical coupling.
• External influences: External factors like electric fields, chemical signals, or mechanical forces can influence ion channel activity and membrane potential, thereby “reprogramming” the circuit.

So, what do these bioelectric circuits actually do? They’re not just buzzing with random electrical activity; they are processing information and controlling cell behavior. They’re like a “control system” for the body’s shape and structure. The bioelectric network receives diverse inputs, integrates it together, and outputs cell behavior.

Think of it like this: The bioelectric circuit “knows” what the correct shape of a tissue or organ should be. This “knowledge” is encoded in the pattern of electrical activity within the circuit – the bioelectric code. If the tissue is damaged, or if development goes astray, the bioelectric circuit detects this deviation from the “target morphology” and initiates corrective actions.

How does the circuit “know” the correct shape? This is still an area of active research, but it likely involves a combination of factors:

• Genetic information: Genes provide the “blueprint” for building the body, including specifying which ion channels and gap junctions are produced.
• Mechanical forces: The physical forces acting on cells can influence their bioelectric state and their interactions with neighboring cells.
• Previous history: The bioelectric pattern can retain a “memory” of the previous state, helping to guide regeneration or repair. This is the pattern homeostasis aspect of it.

The bioelectric circuit controls cell behavior through several key mechanisms:

• Cell Proliferation: Changes in membrane potential can influence whether a cell divides or not.
• Cell Differentiation: The bioelectric state can help determine what type of cell a cell will become (e.g., a muscle cell, a skin cell, a nerve cell).
• Cell Migration: Electric fields can guide the movement of cells, directing them to the right place during development or wound healing.
• Apoptosis (Programmed Cell Death): Bioelectric signals can trigger the self-destruction of cells that are damaged or no longer needed. This is important for sculpting tissues and removing abnormal cells.

Let’s consider some specific examples of bioelectric circuits in action:

• Planarian Regeneration: As we’ve discussed, planarians have an incredible ability to regenerate. This is controlled by a bioelectric circuit that “remembers” the original body plan. By manipulating ion channels and gap junctions, researchers can alter this circuit, causing the worm to regenerate with a different head shape or even multiple heads. This is a dramatic demonstration of the reprogrammability of bioelectric circuits.
• Frog Embryo Development: In frog embryos, bioelectric gradients guide the formation of the body plan. For example, a specific pattern of voltage across the early embryo helps determine where the face will form. Disrupting this pattern can lead to facial defects.
• Wound Healing: When you cut yourself, a bioelectric signal is generated at the wound site. This signal helps to attract cells to the area, stimulate cell division, and guide the formation of new tissue.
• Left-Right Patterning. The very fact of an animal having mirrored symetrical organs implies this ability, from cytoskeletal polarity, and the way information has to go through bioelectric networks in tissues, acting “computationally”, setting up patterns like gradients that serve as a blue-print.

Crucially, bioelectric circuits are not limited to the nervous system. While the nervous system is a specialized type of bioelectric circuit, designed for rapid, long-distance communication, bioelectric circuits exist in all tissues, coordinating cell behavior at a local level. Think of the nervous system as the “high-speed internet” of the body, while bioelectric circuits are the “local area network” within each tissue and organ. They do interact, however; Neurons affect tissue by bioelectricity!

When bioelectric circuits go wrong, it can have serious consequences:

• Developmental Defects: Disruptions in bioelectric signaling during development can lead to birth defects, like the facial malformations seen in frog embryos with altered voltage patterns.
• Regeneration Failure: If the bioelectric circuit “forgets” the correct body plan, regeneration may fail or produce abnormal structures.
• Cancer: As we’ve discussed, cancer cells often have abnormal membrane potentials and disrupted gap junction communication. This can lead to uncontrolled cell growth and metastasis. By restoring normal bioelectric patterns, it’s sometimes possible to normalize cancerous growth, reverting tumor cells to a more normal state.

The emerging understanding of bioelectric circuits opens up exciting possibilities for:

• Regenerative Medicine: By manipulating bioelectric signals, we might be able to stimulate the regeneration of lost limbs, organs, or tissues.
• Cancer Therapy: By correcting the aberrant bioelectric patterns in tumors, we could potentially develop new, less toxic cancer treatments.
• Treatment of Developmental Disorders: By understanding how bioelectric signals go wrong during development, we might be able to prevent or correct birth defects.
• Synthetic Bioengineering: By designing artificial bioelectric circuits, we could potentially create new biological structures and devices, like artificial organs or “living machines.”

In summary, bioelectric circuits are a fundamental control system for shape and form in living organisms. They are dynamic, reprogrammable networks of cells that communicate and coordinate their activity through electrical signals. They are not just a byproduct of cellular activity; they are active information processors that guide development, regeneration, and maintain tissue homeostasis. Understanding and learning to control these circuits will revolutionize medicine and biology.

Michael Levin Bioelectricity 101 Crash Course Lesson 25: Bioelectric Circuits: The Body’s Control System for Shape Quiz

1. What is a bioelectric circuit?

A) A circuit found only in the brain.
B) A network of cells that communicate through electrical signals.
C) A type of electronic circuit used in computers.
D) A system for generating electricity from biological sources.

2. Which of the following is NOT a key component of a bioelectric circuit?

A) Ion channels
B) Gap junctions
C) Membrane potential
D) DNA polymerase

3. What is the role of gap junctions in a bioelectric circuit?

A) They block the flow of ions between cells.
B) They allow direct electrical communication between adjacent cells.
C) They generate action potentials.
D) They synthesize proteins.

4. True or False: Bioelectric circuits are static and unchanging.

A) True
B) False

5. What does it mean for a bioelectric circuit to be “reprogrammable”?

A) Its pattern of electrical activity can be altered.
B) It can be surgically removed and replaced.
C) It can only function in one specific way.
D) It is resistant to any changes.

6. Which can act to “reprogram” the bioelectric circuit?

A) Changing Ion Channels
B) Changes to Gap Junctions
C) Outside influence, like chemicals.
D) All of the above.

7. What kind of information do bioelectric circuits process?

A) Information about the desired shape and structure of the organism.
B) Information about the external environment.
C) Information about the time of day.
D) Information about the individual’s thoughts and feelings.

8. Which cell behaviors can be controlled by bioelectric circuits?

A) Cell proliferation
B) Cell differentiation
C) Cell migration
D) All of the above

9. What structure’s morphology does the bioelectric code determine and “know?”

A) Target morphology
B) The Genome
C) Gap Junctions
D) A and C.

10. How is a bioelectric circuit *analogous* to an electronic circuit?

A) They both use electrons to transmit signals.
B) They both have components that interact to process information.
C) They are both found only in computers.
D) They are both made of metal.

11. Disruptions in bioelectric circuits can lead to:

A) Improved health.
B) Developmental defects, regeneration failures, and cancer.
C) Enhanced athletic performance.
D) Increased intelligence.

12. The “target morphology” is:

A) The current shape of a tissue or organ.
B) The desired or “correct” shape of a tissue or organ.
C) The shape of a single cell.
D) The shape of a DNA molecule.

13. True/False: The target morphology of a bioelectric circuit cannot change at all.

A) True
B) False.

14. Planarian regeneration is remarkable since it exhibits robust regeneration, no matter what part gets cut, suggesting bioelectric states’ role of ___.

A) Nothing at all, it’s purely genetic
B) Fast signaling
C) Regeneration.
D) B and C

15. What kind of communication occurs at the gap junctions?

A) Long distance
B) Chemical
C) Direct electric
D) Very indirect and delayed communication.

16. What happens when gap junctions are blocked?

A) Hyperpolarization
B) Nothing
C) Lowering of membrane potential
D) All of the Above

17. What does a dynamical-systems approach reveal about developmental robustness and the nature of “determinant genes” or master regulators?

A) That they are the beginning, middle, and end of control, a straight line
B) Genes alone control and determine.
C) A much more complex and subtle approach to top-down “driving” needs to occur to really determine what such determinant genes actually “do”.
D) None of the above.

18. Which helps account for tissue scale behaviors and control that chemical components can’t entirely describe by itself?

A) Bioelectricity
B) Sodium levels
C) Genetic codes.
D) Motor proteins, like myosin

19. True/False: the idea of bioelectric circuits highlights an integration with systems biology, regenerative medicine, and even possibly artificial life?

A) True
B) False

20. True/False: Bioelectric patterns represent an emergent phenomenon.

A) True
B) False.

Michael Levin Bioelectricity 101 Crash Course Lesson 25: Bioelectric Circuits: The Body’s Control System for Shape Answer Sheet

1. B

2. D

3. B

4. B

5. A

6. D

7. A

8. D

9. A

10. B

11. B

12. B

13. B

14. D

15. C

16. A

17. C

18. A

19. A

20. A

迈克尔·莱文 生物电 101 速成课程 第25课：生物电回路：身体形态的控制系统 摘要

• 生物电回路是通过电信号进行通信和协调活动的细胞网络。
• 这些回路不仅限于神经系统；它们存在于所有组织中。
• 生物电回路的关键组成部分包括离子通道、间隙连接和单个细胞的膜电位。
• 这些回路是动态和可重编程的；它们的活动模式会随着时间和信号的变化而改变。
• 生物电回路处理有关生物体所需形状和结构（“目标形态”）的信息。
• 它们控制细胞行为，如增殖、分化、迁移和凋亡，以实现和维持该形状。
• 生物电回路类似于电子电路，但它们使用离子而不是电子，并且它们嵌入在活组织中。
• 生物电状态是涌现特性：没有任何单个组件（单个离子通道、单个细胞等）“具有”“正确的电压”或任何类型的解剖设定点。 相反，正是相互作用和动力学产生了我们之前讨论过的电压景观。
• 生物电回路的中断会导致发育缺陷、再生失败和癌症。
• 理解和操纵生物电回路为再生医学、癌症治疗和合成生物工程提供了令人兴奋的可能性。
• 与遗传成分不同，整个电网络的活动是快速的。
• 间隙连接打开时会导致总膜电位降低； 阻塞时，它会升高。
• 生物电是形态纠错的理想候选者，因为它发生在整个组织区域； 它可以帮助解释再生壮举，以及生物结果的自上而下控制。
• 它有助于将分子生物学与组织规模的组织联系起来（这曾经是一个相对被忽视的领域）。

迈克尔·莱文 生物电 101 速成课程 第25课：生物电回路：身体形态的控制系统

在本课程中，我们已经走了很长一段路！ 我们已经了解了离子、离子通道、膜电位、电压梯度，以及这些电现象如何不仅限于神经系统，而且对所有细胞都至关重要。 我们已经看到生物电信号在发育、再生甚至癌症中起着至关重要的作用。 现在，是时候将所有这些片段放在一起，并了解这些单独的组件如何作为一个系统——一个生物电回路——协同工作。

想想电子电路，比如手机或电脑内部的电路。 它具有以特定方式连接的各种组件（电阻器、电容器、晶体管等）。 这些组件相互作用，处理电信号并控制设备的的行为。 生物电回路类似，但它不是使用电子流过电线，而是使用离子流过离子通道和间隙连接。 它不是构建在电路板上，而是嵌入在活组织中。

以下是生物电回路的关键组成部分的细分：

• 离子通道： 这些是控制离子跨细胞膜流动的“门”。 不同类型的离子通道允许不同类型的离子通过，并且它们可以响应各种信号（如电压变化、化学信号或机械力）而打开或关闭。
• 间隙连接： 这些是相邻细胞之间的直接连接，形成允许离子和小分子直接从一个细胞流向另一个细胞的通道。 间隙连接在细胞之间产生电耦合，允许它们共享电信号并协调它们的活动。 可以将它们视为连接相邻细胞的“桥梁”或“隧道”。
• 膜电位 (Vmem)： 每个细胞的膜两侧都存在电压差——膜电位。 这种电压是由细胞内外离子的不均匀分布产生的。 膜电位是生物电回路中的一个关键变量； Vmem 的变化可以充当信号，影响细胞行为。
• 细胞本身： 组织中所有涉及的细胞本身都通过生物电通讯连接或可以感知生物电通讯（例如通过电场）。 这也可以比作电路板上的一组晶体管。

这些组件不是静态的； 它们是动态和相互关联的。 离子通道的活动会影响膜电位，而膜电位又会影响间隙连接的打开或关闭，反之亦然。 这就产生了一个复杂的反馈回路和相互作用网络。 至关重要的是，这个网络会随着时间的推移而改变——它是可重编程的。

说生物电回路是“可重编程的”是什么意思？ 这意味着电路内电活动的模式可以改变，而这种改变可以改变电路内细胞的行为。 这就像重写计算机的软件——你可以在不改变物理硬件的情况下改变指令。

这种“重编程”是如何发生的？ 它可以通过以下方式发生：

• 离子通道表达的变化： 细胞可以产生更多或更少的特定类型的离子通道，从而改变离子流，进而改变膜电位。
• 离子通道活性的变化： 现有的离子通道可以被打开、关闭或修饰，从而改变它们对离子的通透性。
• 间隙连接连通性的变化： 细胞之间间隙连接的数量和强度可以改变，从而改变电耦合的程度。
• 外部影响： 外部因素（如电场、化学信号或机械力）会影响离子通道活性和膜电位，从而“重编程”电路。

那么，这些生物电回路实际上做什么？ 它们不仅仅是嗡嗡作响的随机电活动； 它们正在处理信息并控制细胞行为。 它们就像身体形状和结构的“控制系统”。 生物电网络接收各种输入，将它们整合在一起，并输出细胞行为。

可以这样想：生物电回路“知道”组织或器官的正确形状应该是什么。 这种“知识”被编码在电路内的电活动模式中——生物电代码。 如果组织受损，或者发育出错，生物电回路会检测到这种与“目标形态”的偏差，并启动纠正措施。

电路如何“知道”正确的形状？ 这仍然是一个活跃的研究领域，但它可能涉及多种因素：

• 遗传信息： 基因提供了构建身体的“蓝图”，包括指定产生哪些离子通道和间隙连接。
• 机械力： 作用于细胞的物理力会影响它们的生物电状态以及它们与相邻细胞的相互作用。
• 既往史： 生物电模式可以保留先前状态的“记忆”，有助于指导再生或修复。 这是它的模式稳态方面。

生物电回路通过几个关键机制控制细胞行为：

• 细胞增殖： 膜电位的变化会影响细胞是否分裂。
• 细胞分化： 生物电状态可以帮助确定细胞将变成什么类型的细胞（例如，肌肉细胞、皮肤细胞、神经细胞）。
• 细胞迁移： 电场可以引导细胞的运动，将它们引导到发育或伤口愈合过程中的正确位置。
• 细胞凋亡（程序性细胞死亡）： 生物电信号可以触发受损或不再需要的细胞的自我毁灭。 这对于塑造组织和清除异常细胞非常重要。

让我们考虑一些生物电回路发挥作用的具体例子：

• 涡虫再生： 正如我们所讨论的，涡虫具有令人难以置信的再生能力。 这是由“记住”原始身体形态的生物电回路控制的。 通过操纵离子通道和间隙连接，研究人员可以改变这个回路，导致涡虫再生出不同的头部形状，甚至多个头部。 这是生物电回路可重编程性的一个戏剧性展示。
• 青蛙胚胎发育： 在青蛙胚胎中，生物电梯度指导身体形态的形成。 例如，早期胚胎中特定的电压模式有助于确定面部形成的位置。 破坏这种模式会导致面部缺陷。
• 伤口愈合： 当你割伤自己时，会在伤口部位产生生物电信号。 该信号有助于吸引细胞到该区域，刺激细胞分裂，并引导新组织的形成。
• 左右模式形成. 动物具有镜像对称器官这一事实本身就暗示了这种能力，它来自细胞骨架极性，以及信息必须通过组织中的生物电网络传播的方式，起到“计算”作用，建立像梯度这样的模式作为蓝图。

至关重要的是，生物电回路不仅限于神经系统。 虽然神经系统是一种特殊类型的生物电回路，专为快速、长距离通信而设计，但生物电回路存在于所有组织中，在局部水平上协调细胞行为。 可以将神经系统视为身体的“高速互联网”，而生物电回路是每个组织和器官内的“局域网”。 然而，它们确实会相互作用； 神经元通过生物电影响组织！

当生物电回路出错时，可能会产生严重的后果：

• 发育缺陷： 发育过程中生物电信号传导的中断会导致出生缺陷，就像在电压模式改变的青蛙胚胎中看到的面部畸形一样。
• 再生失败： 如果生物电回路“忘记”了正确的身体形态，再生可能会失败或产生异常结构。
• 癌症： 正如我们所讨论的，癌细胞通常具有异常的膜电位和破坏的间隙连接通讯。 这会导致细胞不受控制地生长和转移。 通过恢复正常的生物电模式，有时可以规范化癌细胞的生长，使肿瘤细胞恢复到更正常的状态。

对生物电回路的新兴理解为以下方面开辟了令人兴奋的可能性：

• 再生医学： 通过操纵生物电信号，我们也许能够刺激失去的四肢、器官或组织的再生。
• 癌症治疗： 通过纠正肿瘤中异常的生物电模式，我们有可能开发出新的、毒性较小的癌症治疗方法。
• 发育障碍的治疗： 通过了解生物电信号在发育过程中如何出错，我们也许能够预防或纠正出生缺陷。
• 合成生物工程： 通过设计人工生物电回路，我们有可能创造出新的生物结构和设备，如人造器官或“活体机器”。

总之，生物电回路是生物体形状和形态的基本控制系统。 它们是动态的、可重编程的细胞网络，通过电信号进行通信和协调活动。 它们不仅仅是细胞活动的副产品； 它们是引导发育、再生和维持组织稳态的主动信息处理器。 理解和学习控制这些电路将彻底改变医学和生物学。

迈克尔·莱文 生物电 101 速成课程 第25课：生物电回路：身体形态的控制系统 小测验

1. 什么是生物电回路？

A) 仅存在于大脑中的电路。
B) 通过电信号进行通信的细胞网络。
C) 计算机中使用的一种电子电路。
D) 从生物来源发电的系统。

2. 以下哪一项不是生物电回路的关键组成部分？

A) 离子通道
B) 间隙连接
C) 膜电位
D) DNA 聚合酶

3. 间隙连接在生物电回路中的作用是什么？

A) 它们阻止离子在细胞之间流动。
B) 它们允许相邻细胞之间进行直接的电通信。
C) 它们产生动作电位。
D) 它们合成蛋白质。

4. 对或错：生物电回路是静态的且不变的。

A) 对
B) 错

5. 生物电回路“可重编程”是什么意思？

A) 它的电活动模式可以改变。
B) 可以通过手术切除和更换。
C) 它只能以一种特定方式起作用。
D) 它能抵抗任何变化。

6. 什么可以“重编程”生物电电路？

A) 改变离子通道
B) 间隙连接的变化
C) 外部影响，如化学物质。
D) 以上都是。

7. 生物电回路处理什么样的信息？

A) 有关生物体所需形状和结构的信息。
B) 有关外部环境的信息。
C) 有关一天中时间的信息。
D) 有关个人思想和感受的信息。

8. 生物电回路可以控制哪些细胞行为？

A) 细胞增殖
B) 细胞分化
C) 细胞迁移
D) 以上都是

9. 生物电代码决定并“知道”什么结构的形态？

A) 目标形态
B) 基因组
C) 间隙连接
D) A 和 C.

10. 生物电回路如何与电子电路类比？

A) 它们都使用电子来传输信号。
B) 它们都有相互作用以处理信息的组件。
C) 它们都只存在于计算机中。
D) 它们都由金属制成。

11. 生物电回路的中断会导致：

A) 改善健康。
B) 发育缺陷、再生失败和癌症。
C) 提高运动表现。
D) 提高智力。

12. “目标形态”是：

A) 组织或器官的当前形状。
B) 组织或器官的所需或“正确”形状。
C) 单个细胞的形状。
D) DNA 分子的形状。

13. 对/错：生物电回路的目标形态完全不能改变。

A) 对
B) 错。

14. 涡虫再生非常出色，因为它表现出强大的再生能力，无论切割哪个部分，这表明生物电状态的作用是___。

A) 完全没有，这纯粹是遗传的
B) 快速信号传导
C) 再生。
D) B 和 C

15. 间隙连接处发生什么样的通信？

A) 长距离
B) 化学
C) 直接电
D) 非常间接和延迟的通信。

16. 间隙连接被阻断时会发生什么？

A) 超极化
B) 没啥
C) 膜电位降低
D) 以上都是

17. 动力学系统方法揭示了关于发育稳健性以及“决定基因”或主调节因子性质的什么？

A) 它们是控制的开始、中间和结束，一条直线
B) 基因单独控制和决定。
C) 需要一种更复杂和微妙的自上而下“驱动”方法才能真正确定这些决定基因实际上“做什么”。
D) 以上都不是。

18. 哪一项有助于解释化学成分本身无法完全描述的组织规模行为和控制？

A) 生物电
B) 钠水平
C) 遗传密码。
D) 运动蛋白，如肌球蛋白

19. 对/错：生物电回路的概念强调了与系统生物学、再生医学甚至可能的人造生命的整合？

A) 对
B) 错

20. 对/错：生物电模式代表一种涌现现象。

A) 对
B) 错。

迈克尔·莱文 生物电 101 速成课程 第25课：生物电回路：身体形态的控制系统 答案表

1. B

2. D

3. B

4. B

5. A

6. D

7. A

8. D

9. A

10. B

11. B

12. B

13. B

14. D

15. C

16. A

17. C

18. A

19. A

20. A