human niutrition Flashcards
Autotrophic
Autotrophs make their own food e.g.
plants
Heterotrophic
Heterotrophs take in food from the
environment. They cannot make their own
food
Heterotrophs can be divided into three main categories;
Carnivores
Herbivores
Omnivores
Carnivores
Animals that
mainly feed on
other animals
example of carnivore
fox
Herbivores
Animals that
mainly feed on
plants
example of herbivores
rabbits
Omnivores
Animals that
mainly feed on
plants and
animals
example of omnivores
humans
What is Digestion?
The physical and chemical breakdown of food into soluble particles
small enough to pass into body cells
Why do we need a digestive system?
To break down large food particles until they are small enough to pass
into body cells
Human Digestive System
a long tube, starting
at the mouth and ending at
the anus.
Stages in Human Digestion
Ingestion
digestion
absorption
egestion
Ingestion
Food is taken into the mouth
Digestion
The breakdown of food. Can be either
chemical or physical
Absorption
Digested food passes from the digestive
system into the blood
Egestion
The removal of the unabsorbed waste from
the digestive system
what does the mouth contain
Contains a muscular
tongue and a set of teeth.
what does the mouth secrete and from where
a juice called
saliva from the salivary
glands.
what does saliva contain
water,
salts, and the enzyme
Salivary amylase.
Humans have four types of teeth;
incisors, canines, premolars and molars.
Incisors
shaped like chisels and cut and slice food
Canines
long, pointed and fang like. They tear food
Premolars
large, flat teeth and are used to crush and grind food
Molars
large teeth which cut and grind food
Human Dental Formula
2 incisors, 1 canine, 2 premolars aand 3 molars
Oesophagus
A hollow muscular tube, 25 cm long that connects the pharynx to the stomach.
Oesophagus job
The walls of the Oesophagus secrete mucus and the food is moved by Peristalsis