BioPsych Exam 3 Flashcards
Digestion
breaking down food and absorbing its constituents
Parotid Gland
by ear
- when you eat something sour it activates
- secrets chemicals that break down starch
Salivary gland
along jawline
- Lubricates the food as it is chewed so it can work its way down the esophagus
Esophagus
pushes food down to the stomach
stomach
“holding place” for food
- Hydraulic acid breaks down food in the stomach
Pyloric Sphincter
opens and closes to regulate how much food moves out into the intestines
- like a faucet
Duodenum
First third of the small intestine
- Sugars, amino acids, fats, are absorbed in duodenum
- Simple sugars, glucose, and amino acids easily pass through
- Fats pass through channels in the duodenum to make it to the bloodstream
Jejunum
absorbs extra nutrients that the duodenum didnt get
Ileum
- Picking up any remains
- Usually doesn’t get much
- Absorbs lots of Vitamins, minerals, water
Energy delivered
- lipid and fatty acid
— fats - amino acids
— protein - glucose
— sugar
Energy stored
- triglyceride
— stored under the skin - Protein
— stored in muscle tissue - Glycogen
— stored in liver and muscle tissue
— type of sugar, easily converted
Cephalic Phase and Absorptive phase
insulin levels are high / glucagon levels are low
- before you eat, can be triggered by thinking or smelling food
Fasting phase
no longer absorbing nutrients
- food has moved through small intestine and we now rely on stored energy
evolution of tastes
typically prefer sweet, fatty, and salty foods
- In nature, sweet and fatty foods tend to be higher in “nutrient value” and energy, than less sweet/fatty food
- Salty foods are high in sodium, needed for electrolyte balance in the body
- Bitter tastes are typically not favored because they are generally associated with toxins and spoilage
modeling of preferences
- Prefer flavors found in mother’s milk and on breath of others
- May develop preference for foods eaten by others
Vitamins and Minerals
- Prefer foods that are good sources of vitamins and minerals, especially when there is a deficiency
Pre-meal hunger
- People that eat on a schedule , Body knows how much time has passed so the cephalic phase starts
Conditioning of Hunger
- cues associated with food can trigger cephalic phase then trigger what you want to eat
— always doing the same while eating can cause hunger while doing it
Hunger peptides
- Ghrelin
- Neuropeptide Y
Ghrelin
- Hunger peptide
- primarily produced and released by stomach, signaled by duodenum
Neuropeptide Y
- hunger peptide
- released by neurons in hypothalamus
- specifically the arcuate nucleus
- preference for carbs
Satiety Signal study on rats
when they lowered nutrient level below 50%, they stopped eating all together
