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.
Why is it important for teenagers to have a diet rich in calcium?
Calcium helps to prevent osteoporosis as females lose bone calcium as they age.
What is a broken bone called?
A broken bone is called a fracture.
What are the different types of fractures?
There are three different types of fractures - a compound fracture, a simple fracture and a greenstick fracture.
What is a greenstick fracture?
A greenstick fracture is when a bone is not completely broken.
What is a simple fracture?
A simple fracture is when a bone is cleanly broken.
What is a compound fracture?
A compound fracture is when the broken bone breaks through the skin.
What is a joint?
A joint is when two or more bones meet.
What is a fixed joint?
A fixed joint is found in the skull where the bones cannot move.
Where is a hinge joint found?
A hinge joint is found in the elbow and knee.
Where are ball and socket joints found?
Ball and socket joints are found in the shoulder and hip.
What does a ligament do?
A ligament connects bones to each other.
What does a tendon do?
A tendon connects a muscle to a bone.
What do muscles do?
Muscles move bones.
What is osteoporosis?
Osteoporosis is when the bone degenerates.
What are synovial joints and why are they called this?
Synovial joints are ball and socket joints and hinge joints and are called this because they contain synovial fluid.
What is antagonistic muscle?
Antagonistic muscles work against each other. While one muscle contracts the other relaxes and vice versa.
Why should you not move a broken bone?
You should not move a broken bone because nerves and blood vessels could be damaged.
What does synovial fluid do?
Synovial fluid absorbs shock and acts as a lubricant.
What is a fulcrum?
Pivot Point around which a lever arm rotates.
What are the components of a lever system?
- fulcrum
- forces
- lever arm
