Vertebrates vs Invertebrates

Vertebrates

Vertebrates are animals with a skeleton. The skeleton is made up of bones. The bones are joined together to hold the body up. They protect some parts of the body.
Vertebrate bodies have several parts:

• The head: Vertebrates have a skull to protect their brain.
• The trunk: They have a spinal column, ribs, shoulders and hips in the trunk.
• The limbs: Some vertebrates have legs. Others have wings or fins. Some vertebrates like snakes, have no limbs. Limbs' bones should be long. 
• The tail: This is an extension of the spinal column. Very small vertebrae make up the tail.

Have a look to the following videos:

Invertebrates
Invertebrates animals have no bones (no skeleton).

Some invertebrates have a protective covering:

• Shells are hard and strongs. For instance: a mussel
  
  
   
• Exoskeleton can be thick or thin: For instace: 

• Crabs have thick exoskeletons

• Beetles have thin exoskeletons

Other invertebrates, like jellyfish and worms have no protective covering.

Watch the video:

Insects

Insects are a kind of invertebrates.

All of them have:

• A head : with two eyes, a mouth and two antennae.
• A thorax : In the thorax we can find almost always two or more wings (there are some insects without wings). However all insects will have six legs. If they do not have six legs, they are not insects.
• An abdomen : It is always joined to the thorax. 

Insects are born from eggs. 

Young insects are called larvae. Some larvae are caterpillars. They have no wings or antennae.

All insects breathe air.

Some insects like butterflies are herbivores.

Other insects like dragonflies are carnivores.

Others, like flies are omnivores.

https://www.youtube.com/watch?feature=player_embedded&v=EoLFR3owpfY

Most part of information and images are taken from the book: Essential Science 4. Science, Geography and History (2006). Santillana Education, S.L / Richmond Publishing