UK GCSE level age ~14-16, ~US grades 9-10 Biology revision notes re-edit 23/05/2023 [SEARCH]

Skeleton and muscles: 4. The structure and function of teeth

Doc Brown's Biology exam study revision notes


There are various sections to work through,

after 1 they can be read and studied in any order.

INDEX of biology notes on the skeleton and muscles


(4) The structure and function of teeth

Although teeth are not considered part of the skeletal system, teeth are made out of bone-like material (plus soft tissue) and also involve muscle action to work the jaw bones!

The four main types of human teeth

Teeth are NOT bone, but they are anchored to the jaw bones.

Designed for the crushing of food - mechanical digestion of food.

Image adapted from

Molars - the biggest teeth, large flat ridged surfaces to grind and chew food into smaller pieces that are easy to swallow.

Pre-molars - have many ridges and their main function is to chew and grind up food.

Canines ('fangs') - the strongest, but smaller sharpest pointed front teeth are used for biting food - you use them to bite into food first.

Incisors - flat sharper front teeth for tearing food, and used in first biting action too. They also support the lips.

The structure of the human tooth

image adapted from

The crown is the visible top part of your tooth and the 'invisible' root extends down below the gum line and helps anchor the tooth to the jaw bone.

Enamel coating - is the hardest and most mineralised part of a tooth that covers and protects the tooth crown.

Dentine - is the substance between the enamel or cementum and is a mineralised tissue not as hard as enamel, so susceptible to decay if the enamel is worn away.

Pulp - the central region of the tooth and contains the blood vessels, nerves and softer tissues that delivers nutrients and signals to and from the tooth.

Gums - tissue that covers the root of the tooth.

Cementum - a specialized bone like substance covering the root of a tooth and helps tether the root firmly to the jaw bones.

Bone - the root of the tooth is anchored to the jaw bone.

Blood vessels - bring nutrients and oxygen to the teeth cells, note the network of blood vessels and nerves right up to near the dentine.

Nerves - the inner softer tissue of teeth contain neurons which are part of the peripheral nervous system - very effective in sending pain signals to the brain if the tooth is infected, ouch!!!

Dental decay and plaque

Your teeth get coated with bacteria and food.  The bacteria respiring sugars in the food producing acidic molecules.  The acids dissolve the enamel and dentine.

The bacteria and undigested food and saliva form soft deposits called plaque which hardens with salts to form a deposit called calculus. Both plaque and calculus act as food reservoirs by absorbing sugars on which the bacteria can feed on.

Looking after your teeth and gums.

Brush your teeth regularly, which clears out residual food and bacteria so the acidic molecules are not formed in the first place - prevention is better than cure (if possible!) at the dentist.

It is not good to consume too many sugary foods or drinks on which the acid producing bacteria can feed on.

Calcium ions are an important component of the harder bone tissues, so your diet should include sources of calcium like milk, cheese, yogurt, nuts and green leafy vegetables.

Although very rare, lack of vitamin C from fruit and vegetables can lead to scurvy whose effect includes bleeding gums - gum disease.



INDEX of biology notes on the skeleton and muscles


This is a BIG website, so try using the [SEARCH BOX], it maybe quicker than the many indexes!

email doc brown - comments - query?

UK KS3 Science Quizzes for KS3 science students aged ~11-14, ~US grades 6, 7 and 8

BiologyChemistryPhysics UK GCSE/IGCSE students age ~14-16, ~US grades 9-10

Advanced Level Chemistry for pre-university ~16-18 ~US grades 11-12, K12 Honors

Find your GCSE/IGCSE science course for more help links to all science revision notes

Use your mobile phone or ipad etc. in 'landscape' mode?

Website content Dr Phil Brown 2000+. All copyrights reserved on revision notes, images, quizzes, worksheets etc. Copying of website material is NOT permitted. Exam revision summaries & references to science course specifications are unofficial.