Nutrition Flashcards
Herbivores
Animals that only eat plant materials
e.g. Sheep, cattle and rabbits
Different groups of animal according to what they feed on
- Herbivores
- Carnivores
- Omnivores
Carnivores
- Animals that only eat other animals
- e.g. Cats, hyenas and lions
Omnivores
- Feed on both plant and animal matter
- e.g. Humans, pigs and baboons
Specific arrangement of teeth for a specific food source
Dentition
Four main types of teeth
- Incisors
- Canines
- Premolars
- Molars
Structure and function of incisors in humans
Chisel shaped for biting off pieces of food
Structure and function of canines in humans
Slightly longer than incisors with a point for biting and tearing off pieces of food
Structure and function of premolars in humans
- Have one or two blunt points (cusps)
- Used to chew or crush food into small pieces
Structure and function of molars in humans
- Larger than premolars, they have four or more blunt points (cusps)
- used to chew or crush food into small pieces
Herbivore lifestyle
- Spends most of the time grazing low energy foods
- No active chasing of prey
- Smaller herbivores need to escape predators
Carnivore lifestyle
- Very active when hunting and chasing prey
- Very inactive between hunts
Omnivores
- Relatively more active than herbivores
- Often opportunistic feeders
Dentition of a herbivore
- Sharp incisors for chopping vegetation
- Often canines absent and a large gap between incisors and molars
- Large flat premolars and molars for grinding food
Dentition of a carnivore
- Pointed incisors for tearing meat
- Long elongated canines for gripping and puncturing prey
- Sharp strong premolars and molars for crunching small bones
Dentition of an omnivore
- Chisel shaped incisors for biting
- Canines for tearing
- Flatter premolars and molars for grinding and crushing
Ingestion
The intake of food through the mouth
Digestion
The mechanical and chemical breakdown of food
Absorption
The diffusion of simple food molecules through the intestinal wall into the blood
Assimilation
Incorporation of nutrients shuch as amino acids and glucose into the cells
defecation / egestion
The removal of undigested and unabsorbed waste from the body through the anus in the form of faeces
Structure and function of the parts of the mouth
- Teeth (mechanically break up food)
- Tongue (tasting, helps push food under teeth and to form food bolus)
- Hard and soft palate (roof of mouth)
- Stratified epithelium (lines mouth)
- Salivary glands (provides saliva)
- Uvula (closes off the nasal passage during swallowing)
Structure and function of pharynx
Pharynx (throat) leads to the oesophagus (gullet) and trachea (windpipe)
intersection of nasal passages and alimentary canal
Epiglottis (closes over the opening to the trachea)
Structure and function of the oesophagus
Muscular tube (joining pharynx to the stomach) Lined with stratified epithelium (thick and layered) Muscles (peristaltic action to move food quickly to stomach)