Hunger and Chemical Senses Flashcards
(20 cards)
What signals that you are hungry?
Low glucose levels. Important since brain cannot use fat energy for fuel
Glycogen
Stored form of glucose found in liver
Insulin
Secreted by pancreas to increase uptake of glucose by cells, and therefore decreasing blood sugar level
NPY
appetite stimulant. High hypothalamus activity driven by NPY associated with increased food-seeking behaviours
CCK
Produced by small intestine to promote short-term satiety. Promotes short term eating behaviours like ending a meal, but not long-term weight regulation.
Adipose
Also called fat. Form of long-term energy storage and recently classified as endocrine organ
Leptin
Secreted by adipose tissue and controlled by OB gene. reduces appetite to maintain long-term energy storage. Inhibits NPY in hypothalamus.
Endogenous Opioids
Naturally occurring chemical substance that contribute to palatability and reward-driven feeding
Taste buds
Highly sensitive tasters. Vary in numbers by individual. Taste preferences adapted for calorie-seeking consumption
Chemical Senses
Taste identifies type of taste. Smell identifies intricacies of flavour
Sweet
Signifies energy rich foods
Salt
Signifies foods high in electrolytes
Bitter and Sour
Signifies unsafe foods
Umami
Detects amino acids glutamate and aspartate
Taste Receptor Cells
50-150 within each taste bud. Can detect all types of taste
Taste Pathways
- Medulla to thalamus. Info sent to somatosensory cortex and gustatory cortex
- Pons to hypothalamus and amygdala. Associated with satiety
Somatosensory cortex
Processes feel and texture of food
Gustatory cortex
processing center for taste
Olfactory cilia
chemical molecules enter through naval cavities and dissolve in mucus of nose and begin to interact with olfactory receptor cells. Creates unique pattern of firing of action potential that travels down axons in synapses of olfactory bulb of brain
Glomeruli
processed in higher brain areas including hypothalamus and areas of limbic system
