B5 - Skeletons Flashcards
What is an external skeleton?
An external skeleton is a hard skeleton on the outside of the body.
What is an external skeleton made from?
It is made of a material called chitin.
What is an internal skeleton?
An internal skeleton is a skeleton on the inside of the body.
What is an internal skeleton made from?
It is made of a material called cartilage or bone.
Which areas are made from cartilage?
The outer ear, nose and ends of long bones are made from cartilage.
What is the difference between cartilage and bone?
Cartilage is softer and more flexible than bone.
Why does a jellyfish collapse when it is out of water?
It does not have water to support it.
What are the main advantages to an internal skeleton?
- forms a framework for the body
- grows as you grow
- allows muscles to be easily attached
- has many joints to give flexibility
- is made from living tissue
Why are long bones hollow?
It means they will be stronger, lighter and less likely to break.
What is inside of the bone?
Inside of the bone there is bone marrow which contains blood vessels.
What does cartilage do?
Cartilage absorbs shock and helps bones to slide over each other in joints.
Why do insects shed their skeleton?
To allow them to grow.
Why do bone and cartilage repair themselves quickly?
They repair quickly because they are living tissue.
What is ossification?
Ossification is the process of calcium salts and phosphates being deposited into bone to make it hard.
Why does a pad of cartilage remain at the end of bones in adults?
Cartilage remains at the end of bones so that it can absorb shock and prevent bones from breaking.
