Candy Neuron

The brain is a mosaic of different cell types, each with their own unique properties. The most common brain cells are neurons and glia. MagLab researchers use the world’s strongest MRI to create images of these cells and understand them better.

Neurons are the building blocks of the brain. These cells send and receive electrical and chemical signals, organized into patterns and networks within the brain, communicating with each other at incredible speeds, and transmitting information to other neurons, muscles, and tissues throughout the body. This is what allows your brain to do everything from breathing to talking, eating, walking, feeling, thinking, and comprehending the world around you.

Glia, a Greek word meaning glue, are the support cells of the brain. They provide neurons with nourishment, protection, and structural support.

The average adult brain contains approximately 100 billion neurons as well as trillions of glia. Each neuron is connected to more than a thousand other neurons, making the total number of connections in the brain around 60 trillion!

Neurons vary in size, shape, and structure depending on their role and location. However, nearly all neurons have three essential parts: a cell body, an axon, and dendrites.

Parts of a Neuron

Figures 1: Parts of a Neuron

Image credit: John Childs

Cell body

Also known as a soma, the cell body is the core section of the neuron. The cell body contains genetic information, maintains the neuron’s structure, and provides energy to drive activities.

Like other cell bodies, a neuron’s soma contains a nucleus and specialized organelles. It’s enclosed by a membrane that protects it and allows it to interact with its immediate surroundings.

Axon

The axon is a long, tail-like structure. It joins the cell body at a specialized junction called the axon hillock. Neurons usually have one main axon. Many axons are insulated with a fatty substance called myelin.

Myelin

Myelin helps axons conduct an electrical signal, acting as an insulator to minimize dissipation of the electrical signal as it travels, greatly increasing the speed of conduction. The myelin sheath is not part of the neuron and is produced by glial cells.

There are periodic gaps in the myelin sheath called nodes of Ranvier, which are sites where the signal is “re-charged” as it travels along the axon.

Dendrites

Dendrites are tree-like structures that extend away from the cell body to receive neurotransmitters from other neurons. Some types of neurons do not have any dendrites, some types of neurons have multiple dendrites.

Dendrites can have small protrusions called dendritic spines, which further increase surface area for possible connections with other neurons.

Synapses

Synapses are the specialized junctions where dendrites interface, passing signals between neurons. There is a small gap between two synapsed neurons, where neurotransmitters travel from one neuron to the next.

Types of neurons

1. Sensory neurons carry information from the sense organs (such as the eyes and ears) to the brain.
2. Motor neurons control voluntary muscle activity, such as walking and talking, and carry messages from nerve cells in the brain to the muscles.
3. Interneurons are situated between sensory and motor neurons. Their primary function is integration. They carry sensory information and regulate motor activity. The more complex a response to stimuli is required, the more interneurons are activated. Interneurons are utilized in all higher functions, including cognition, learning, memory, and planning.

What you’ll need:

1. Print out the neuron template. If you can’t print, use a paper plate to draw the template.
2. Vanilla frosting
3. Various candy

Candy suggestions for each part of the neuron:

1. Gummy peach ring (Soma)
2. Sour Punch Straws or Bites (Cell Body)
3. Skittles or M&M's (Nucleus)
4. Twizzlers (Axon)
5. Sour Gummy Worms (Axon terminal, dendrites)
6. Marshmallows, Marshmallows, Mike & Ikes (myelin sheath)

What you'll do:

1. Spread a layer of vanilla frosting onto the area where you want to place a piece of candy
2. Use the frosting to “glue” the candy in place.
3. Use the candies suggested to match the shape of each part of the neuron.
4. If you build the candy neuron on the paper plate, you can also label the parts as you go.

Did you know?

• As a fetus develops inside the womb, neurons grow at the rate of 250,000 per minute. At birth, a baby’s brain consists of around 10 million cells.
• At any given time, only four percent of your brain cells are active. The rest are kept in reserve.
• The nervous system can transmit impulses at a tremendous speed of up to 180 miles per hour.
• Sodium, potassium, and Vitamin B are among the essential nutrients needed for a healthy nervous system.