/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 24 Gap junctions are formed by ____... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 4: Problem 24

Gap junctions are formed by ________. a. gaps in the cell wall of plants b. protein complexes that form channels between cells c. tight, rivet-like regions in the membranes of adjacent cells d. a tight knitting of membranes

Short Answer

Expert verified
b. protein complexes that form channels between cells

Step by step solution

01

- Understand the function of gap junctions

Gap junctions are specialized intercellular connections that directly connect the cytoplasm of two cells, allowing various molecules and ions to pass freely between cells.
02

- Evaluate the options

Review each given option to determine which best describes the formation mechanism of gap junctions.
03

- Eliminate incorrect options

Option a. 'gaps in the cell wall of plants' is incorrect because gap junctions are found in animal cells, not plant cells. Option c. 'tight, rivet-like regions in the membranes of adjacent cells' and option d. 'a tight knitting of membranes' describe other types of cell junctions, such as tight junctions, not gap junctions.
04

- Choose the correct option

Option b. 'protein complexes that form channels between cells' correctly describes gap junctions, as they are formed by connexin proteins that create channels allowing intercellular communication.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Intercellular Communication
Intercellular communication refers to the ways in which cells communicate with each other. This communication is vital for maintaining homeostasis and coordinating functions across different parts of an organism. Cells use various methods to communicate:
  • Direct Contact: This involves physical contact between cell surfaces. Gap junctions are a perfect example of this type of communication, where channel proteins allow ions and molecules to move freely between adjacent cells.
  • Paracrine Signaling: In this type, cells release signaling molecules that affect nearby target cells.
  • Endocrine Signaling: Here, hormones are released into the bloodstream, affecting distant cells.
  • Synaptic Signaling: Neurons communicate with each other or with muscles through neurotransmitters across synapses.
Gap junctions particularly facilitate direct contact-based intercellular communication by allowing the exchange of small signaling molecules and ions, thus ensuring coordinated cellular activity.
Cell Junctions
Cell junctions are structures that connect cells to one another. These structures provide mechanical support, facilitate communication, and regulate the passage of materials between cells.
  • Tight Junctions: These junctions create a watertight seal between cells, preventing the leakage of materials.
  • Desmosomes: They function like spot welds, holding cells together and providing mechanical strength.
  • Gap Junctions: These are channels formed by protein complexes known as connexins, allowing direct communication between cells.
Gap junctions distinguish themselves by enabling the free flow of ions and small molecules. This allows cells to synchronize their activities swiftly, which is especially important in tissues like the heart, where coordinated contraction is necessary for pumping blood effectively.
Connexin Proteins
Connexin proteins are the building blocks of gap junctions. These proteins come together to form hexameric structures known as connexons or hemichannels. When connexons from adjacent cells align, they form a complete gap junction channel.
  • Structure: Each connexon is composed of six connexin protein subunits.
  • Formation: Connexins from two cells must align to create a continuous channel allowing the passage of ions and small molecules.
  • Function: These channels play a crucial role in maintaining homeostasis, enabling the transmission of electrical signals, and facilitating nutrient exchange.
These protein complexes are essential for the proper function of many tissues, including cardiac and neural tissues, where fast and efficient intercellular communication is critical for physiological processes.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Which of the following do not play a role in intracellular movement? a. intermediate filaments and microtubules b. microfilaments and intermediate filaments c. microfilaments and microtubules d. only intermediate filaments

Some animal cells produce extensive extracellular matrix. You would expect their ribosomes to synthesize large amounts of which of the following proteins? a. actin b. collagen c. myosin d. tubulin

Cells lining the intestine absorb a lot of nutrients. How did those cells adapt to their function? a. Cells use cilia to move nutrients to their surface. b. Cells grow much larger than adjacent cells to increase intake c. Cells are flat and thin to absorb more nutrients. d. Membrane folds called microvilli increase the surface area.

Which of the following molecules are typically found in the extracellular matrix? a. nucleic acids such as DNA b. peptidoglycans c. cellulose d. proteoglycans

Mitochondria have DNA that encode proteins related to the structures and functions of the organelles. The replication appears to occur continuously, however, many questions about control of replication rate and segregation during mitosis are yet unanswered. Many diseases are caused by mitochondrial dysfunction. Mitophagy, as the name suggests, leads to the destruction of mitochondria. Predict whether or not cellular control mechanisms involving the regulation of mitochondrial DNA by the nucleus exist. Make use of what you know about selection and homeostasis as they apply to both the organism and to the organelle.
See all solutions

Recommended explanations on Biology Textbooks

Bioenergetics

Read Explanation

Microbiology

Read Explanation

Ecosystems

Read Explanation

Responding to Change

Read Explanation

Control of Gene Expression

Read Explanation

Heredity

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.