Defintions Flashcards
Malnutrition
Incorrect proportions/amounts of nutrients are eaten for a prolonged period of time
Deficiency diseases
Diseases caused due to deficiency of nutrients of our food
Anorexia nervosa
An eating disorder characterised by a fear of gaining weight and results in the person going on a restrictive diet
Bulimia nervosa
An eating disorder characterised by periods of binge eating and then purging
Binge eating
The consumption of large quantities of food in a single sitting
Herbivore
An organism that mainly feeds on plants
Carnivore
An organism that mainly feeds on other organisms (animals/meats)
Omnivore
An organism that feeds on other organisms (plants and animals)
Ingestion
The first process in nutrition. It involves taking food into the mouth
Mechanical digestion
Process that physically breaks the food to increase the surface area for enzyme action
Chemical digestion
Enzymes break complex nutrients into their monomer state so that absorption into the blood can occur
Hydrolysis
Chemical reaction where water is used to breakdown a compound
Salivary amylase
An enzyme that hydrolysis the starch to maltose (two molecules of glucose joined together)
Peristalsis
A series of involuntary contractions of muscles in the walls of the oesophagus-pushing the food towards the stomach
Cardiac sphincter
Located at the top of the stomach and prevents food from moving back into the oesophagus
Pyloric sphincter
Is located at the bottom of the stomach and stops food from moving into the small intestine until it is ready to do so
Stomach
A muscular pouch-like enlargement of the digestive tract
Churning
In the stomach, the food is mixed with gastric juices by peristalsis caused by the strong muscles of the stomach walls. This is an example of mechanical digestion
Pepsin
An enzyme that breaks down proteins into amino acid
Protease
Enzymes that break down proteins
Hydrochloric acid
It makes the contents in the stomach acids, and also kills bacteria that may be in the food
Mucin
A mucous secretion that protects the walls of our stomach from acid gastric juices
Chyme
The food mixes with the gastric juices and then is digested forming a thick soup-like substance
Bile
A watery, alkaline fluid that contains various salts
Absorption
The movement of digested food molecules through the walls of the small intestine
Villi
Millions of very small finger like projections that line the small intestine that is suitable for absorbing digested nutrients
Lymph
Is the fluid that is drained by the lymph vessels from the tissues and cells
Assimilation
The transportation and utilisation of nutrients