๐Ÿ“š

All Subjects

ย >ย 

๐Ÿงฌย 

AP Bio

ย >ย 

๐Ÿฆ 

Unit 4

4.1 Cell Communication

2 min readโ€ขjuly 1, 2020

Annika Tekumulla


The cells in your body communicate in many different ways. Cells must communicate with each other and the environment in order to complete tasks. They communicate through chemical signals. These signals are usually proteins. Multicellular organisms have trillions of cells that communicate in the following ways.ย 

Direct Contact

Direct contact is also calledย juxtacrine signaling. Direct contact occurs when the 2 cells are adjacent to another and occur in both plant and animal cells. In plant cells, theย plasmodesmataย connect one plant cell to another. In animal cells,ย gap junctionsย directly connect the cytoplasm of one animal cell to the cytoplasm of another animal cell. These junctions allow the passage of materials such as ions, signals, and molecules.

Memory Tip: Think of direct contact like a handshake because both people must have direct contact with each other during a handshake!

https://firebasestorage.googleapis.com/v0/b/fiveable-92889.appspot.com/o/images%2F-Fuffu1lgzUoX.webp?alt=media&token=f1862032-de62-4aea-b717-c66690d5e52f

Image courtesy of Giphy.

Paracrine Signaling

Another way that cells communicate is through paracrine signaling.ย 

Paracrine signaling is communication over short distances. Cell sends out signals to nearby cells which causes a change in the behavior of nearby cells. An example of paracrine signaling is contracting muscles. Chemical signals are sent from the nerve to the muscle. This causes the response of changes in the behavior of muscle so that the muscle contracts.

Memory Tip: Think of paracrine signaling as crossing the street. Crossing the street is a short distance and helps me remember that paracrine signaling is between nearby cells. Takes the โ€œright down the streetโ€ phrase into a new perspective!

https://firebasestorage.googleapis.com/v0/b/fiveable-92889.appspot.com/o/images%2F-hCGypTwEJUec.webp?alt=media&token=6c50e90c-bd0f-4f0f-96f4-24393153dfc9

Image courtesy of Giphy.

Synaptic Signaling

Finally, there is synaptic signaling. Synaptic signaling involves a synapse which is the gap between 2 nerve cells.ย 

Signaling occurs when a neuron releases a neurotransmitter. Then, the neurotransmitter moves across the synapse. After it reaches the end of the gap, the neurotransmitter stimulates the adjacent neuron to fire.

Watch AP Bio live streams here.

Resources:

Was this guide helpful?

Join us on Discord

Thousands of students are studying with us for the AP Biology exam.

join now

Browse Study Guides By Unit

โœ๏ธ
Free Response Questions (FRQ)

๐Ÿ‘
General Review

๐Ÿง
Multiple Choice Questions (MCQ)

๐Ÿงช
Unit 1: Chemistry of Life

๐Ÿงฌ
Unit 2: Cell Structure and Function

๐Ÿ”‹
Unit 3: Cellular Energetics

๐Ÿ‘ช
Unit 5: Heredity

๐Ÿ‘ป
Unit 6: Gene Expression and Regulation

๐Ÿฆ
Unit 7: Natural Selection

๐ŸŒฒ
Unit 8: Ecology

Play this on HyperTyper

Practice your typing skills while reading Cell Communication

Start Game