Feeding & Body Regulation Flashcards
Which animals were experiemented on to determine the influence of calory intake on life expectancy?
Worms (Kaiberlain et al, 1986), mice (Weindruch et al, 186) and monkeys (Colman et al, 2014).
What does feeding provide the body with?
Energy intake (calories), micronutrients and essential vitamins and minerals.
Define the process of Energy Homeostasis.
The body’s way of managing energy intake (feeding), energy expenditure (cellular metabolism) and exercise. This is often the reason why attempts to lose or gain weight are unsuccessful.
Does dieting help people lose weight?
In the long-term, dieting does not provide an effective solution for losing weight. As shown in research on force-feeding rats, decreasing food-intake only creates a short-term solution. Energy homeostasis rebuilds the body’s metabolism to its optimal level.
What path do taste molecules take in the brain?
They are transmitted along a specialized neural pathway to the gustatory thalamus then the gustatory cortex.
Which aspects of taste do the stimuli of sodium chloride, acid solution, alkaloid and sugar stimulate?
Sodium chloride - saltiness
Acid solution - sourness
Alkaloid - bitterness
Sugar - sweetness
What are the receptors for saltiness, sourness, bitterness and sweetness?
Saltiness - simple sodium channel
Sourness - hydrogen ions
Bitterness - hydrophobic residue
Sweetness - hydrogen ions
What are the two senses related to flavour?
Taste from the mouth and odours from the nose.
How does the brain recieve information from taste molecules?
1) The relevant stimulus bounds to the taste receptor, then the receptor initiates an action potential in the cell.
2) The cell is then transmitted to the brain and communicates (synapses) with the nucleus of the solitary tract in the brain stem, creating an action potential.
3) Neurons in the solitary tract synapse in the thalamus which processes taste information.
4) The taste information of the thalamus is finally taken to the gustatory cortex.
Why do most animal infants show dislike for bitter flavours?
The stimulus for a bitterness receptor is an alkaloid, which is also known as a poison. With bitterness, the body automatically wants to get rid of the food due to association with poison.
Explain how eating a meal can be described as Pavlovian Conditioning.
The unconditioned stimulus is pre-ingestion consequences and the conditioned stimulus is tasting the meal.
What were the results of Zahorik and Maier (1969)’s experiment using thiamine with rats?
Maintaining rats on a thiamine deficient diet caused them to have a strong preference for foods containing thiamine.
Define Endogenous Opiods.
Peptides made in the brain which produce pleasure, euphoria, relaxation and analgesia (inability to feel pain). They bind to opiod receptors which mediate the effects of morphine and heroin.
Which receptors in the Nucleus Accumbens are important for palatabiltiy?
Opiod receptors.
What is palatability?
The hedonic rewards produced by foods or fluids that are agreeable to your taste buds.
