Signal (biology) facts for kids

A signal in biology is like a secret message that living things send to each other, or from one part of a living thing to another. These messages help organisms understand what's happening around them and inside them. They are super important for how living things grow, react, and survive.

How signals travel inside cells

Signals can be many different things, like:

• Sounds, such as animal calls.
• Ways animals act, like a dog wagging its tail.
• Chemicals, which are tiny molecules that carry messages.
• Electric pulses, especially in our nerves.

How Cells Talk to Each Other

Inside your body, cells are constantly talking! They use signals to tell each other what to do. This communication is called signal transduction. It's how your brain tells your muscles to move, or how your body knows when to grow.

Chemical Signals: The Body's Messengers

Many signals in biology are chemical messages. These chemicals can travel short distances or long distances.

• Hormones: These are special chemicals made in one part of the body that travel through the blood to other parts. For example, hormones tell your body when to grow or when to feel hungry.
• Nerve Signals: Your brain and nerves use electric and chemical signals to send messages super fast. This is how you feel pain, see things, or move your hand.
• Local Signals: Cells can also send chemical messages to their neighbors, telling them to do something specific, like grow or divide.

Electric Signals: The Body's Wires

Sometimes, signals are electric. In biology, these are called biopotentials. They are tiny amounts of electricity created by chemical reactions in cells. Your nerves use these electric signals to send messages quickly from your brain to your body and back again. Think of them like tiny electrical wires carrying information!

Why Are Signals Important?

Signals are vital for all living things. They help:

• Animals find food or avoid danger.
• Plants know when to grow towards the sun.
• Your body fight off sickness.
• Cells work together to form tissues and organs.

Without these amazing signals, living things wouldn't be able to react to their environment or even stay alive!

Images for kids

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  Different types of extracellular signaling

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  Differences between autocrine and paracrine signaling

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  Transmembrane receptor working principle

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  The AMPA receptor bound to a glutamate antagonist showing the amino terminal, ligand binding, and transmembrane domain, PDB 3KG2

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  A G Protein-coupled receptor within the plasma membrane.

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  VEGF receptors are a type of enzyme-coupled receptors, specifically tyrosine kinase receptors

See also

In Spanish: Comunicación celular para niños