Digestion Flashcards
What are the 7 classes of nutrients required by the animal body?
carbohydrates
lipids
proteins
vitamins
minerals
ions
water
What is required for animals to use these nutrients?
digestion - both mechanical and chemical
How does food provide sustenance for life?
food provides the structural and functional building blocks for materials, energy and heat
What are the 2 processes involved in digestion?
assimilation
egestion
What is assimilation?
processes involved in nutrient acquisition, digestion, and absorption
What is egestion?
the excretion of undigested food
Where does assimilation occur?
in the GI tract
What 4 types of cells are in the GI tract?
secretory cells
absorptive cells
muscle cells
neurons
Are nutrients reduced or oxidized from food to generate energy?
oxidized
What determines the amount of energy needed from food for an animal?
the metabolic requirements of the animal
What affects metabolic rates?
body size
activity
growth rate
reproductive state
environmental stress
What is the caloric equivalent?
the energy content per gram of a specific macromolecule
What is the caloric equivalent of proteins and carbs?
4 kcal/g
What is the caloric equivalent of fats?
9 kcal/g
What are vitamins?
a class of nutrients composed of unrelated molecules with diverse functions
What do most vitamins function in?
catalysis as cofactors for enzymes
some are antioxidants
How are most vitamins categorized?
solubility - in water or fat
Which vitamins are fat-soluble?
A
D
E
K
Which vitamins are water-soluble?
B
C
How are vitamins acquired in the body?
in diet or bacteria in the GI tract
What are minerals?
a class of nutrients composed of metallic elements involved in physiology and structure
What are 5 minerals involved in physiology?
calcium
phosphorous
iron
copper
zinc
Why is calcium important in animal bodies?
involved in intracellular cell signalling
bone structure
muscle contraction
neurotransmission
What is phosphorous important for in animal bodies?
bone structure
ATP
phospholipids