Physical Digestion Flashcards
What is physical digestion?
Physical digestion is the mechanical breakdown of food into smaller pieces, mainly by the action of the teeth, to increase the surface area for enzyme action during chemical digestion.
What is the function of teeth in digestion?
Teeth perform mechanical digestion by cutting, tearing, crushing, and grinding food to make it easier to swallow and to increase surface area for enzymes.
What are the four types of human teeth and their functions?
Incisors: Chisel-shaped, 1 root, for cutting and biting food
Canines: Pointed, 1 root, for grasping and tearing food
Premolars: Flat with cusps, 2 roots, for crushing and grinding food
Molars: Larger with more cusps, 2 or 3 roots, for crushing and grinding food
What are milk teeth and when do they appear?
Milk teeth are the first set of teeth, usually 20 in total, appearing between 3 months and 3 years of age. They begin to fall out around age 7.
What are permanent teeth and when do they appear?
Permanent teeth replace milk teeth and are fully present by about age 17. Adults usually have 32 permanent teeth, including 4 wisdom teeth.
What are wisdom teeth?
Wisdom teeth are the last set of molars at the back of the jaw. They are the final permanent teeth to grow in.
What is the structure of a typical tooth?
Enamel: Hard protective outer layer
Dentine: Softer bone-like layer beneath enamel
Pulp cavity: Contains nerves and blood vessels
Crown: Visible part of the tooth
Root: Anchors tooth in the jaw
Cement: Secures the tooth to the bone
Gum: Surrounds the base
Jaw bone & Fibres: Support the tooth
What role do fluorides play in dental health?
Fluorides help prevent tooth decay by strengthening tooth enamel, especially in developing permanent teeth.
What are the risks of excessive fluoride in the environment?
Excess fluorides can harm trees, grass, and animals by entering the food chain. In humans, swallowing fluoridated toothpaste can be harmful, especially for children.
Why is mechanical digestion important before chemical digestion?
It increases the surface area of food, making it easier for enzymes to act efficiently during chemical digestion.
What are fluorides?
Fluorides are compounds of the element fluorine. In small amounts, they help strengthen tooth enamel and protect against tooth decay, especially in developing permanent teeth.
