Week 9: Biological psychology: biology of thermoregulation and eating behaviour in humans Flashcards
_______________ is the regulation of body temperature, usually within a specific range.
Thermoregulation
________ can regulate their body temperature via metabolic processes (‘warm blooded’ animals, including humans).
Endotherms
_________ animals can stay active in cold weather, but they need more energy to heat their bodies and therefore need more food.
Endothermic
__________ have a body temperature that is influenced by the external environment (incorrectly known as ‘cold blooded’).
Ectotherms
__________ animals do not need energy to heat themselves but as a result they are inactive in cold weather.
Ectothermic
If an animal has a low metabolic rate it is a __________.
ectoterm
If an animal has a high and very stable internal temperature it is an _______.
endoterm
What of the following is NOT a natural insulator?
Fur
Teeth
Blubber
Feathers
Eyes
Hair
Colouration
Teeth and eyes
In a colder environment, an animals’ metabolism
________ to __________
their internal body temperature.
increases, raise
Which of the following are instances of behavioural thermoregulation?
Timing of activities
Cooling techniques (eg. panting)
Hibernation
Posture
Torpor
Timing of activities
Hibernation
Standing in water
Torpor
In order to stop things such as overheating, the human body has several ways of regulating temperature. Which of the below help with thermoregulation?
Vasoconstriction
Coughing
Sneezing
Sweating
Increase activity
Decrease activity
Shivering
Vasoconstriction
Sweating
Increase activity
Decrease activity
Shivering
__________ provides carbohydrates, proteins, & fats for metabolism
Eating
_______ rate changes with age, sex, body fat, activity & diet
Metabolic
__________ is used for body heat & work: transport, synthesis, storage
Energy
Hypothalamic ______ _______ controls heat homeostasis.
THERMOREGULATORY CENTER
_________ regulates anabolic cell activities & glucose uptake in cells
Insulin
Maintaining _________ takes approximately 50% of our energy
controls heat homeostasis
homeostasis
COUNTERCURRENT HEAT EXCHANGE
Warm and cold blood flow in opposite directions
to regulate the temperature (arteries & veins)
* Usually around the brain/head region
Behavioural thermoregulation occurs through:
___________ (e.g. lizard increases temperature by “spread eagle”
posture on top of a hot rock)
__________ (e.g. turning its back to the sun)
microclimate
orientation
Torpor, hibernation, estivation, Timing of activities, “Cooling off” techniques are examples of ________ thermoregulation.
behavioural
Reduced metabolic activity and body temperature for
less than a day (endotherm)- governed by circadian
rhythm, ________ or mini hibernation.
torpor
During torpor animals stop foraging. True/False
False
Animals continue foraging
During hibernation animals usually do not forage but rely on energy
stores (food caches or body energy reserves). True/False
True
Long-term torpor (can be 6 months) occurring in the
winter months (endotherms & ectotherms), to
conserve energy.
Hibernation
__________ – active at night
e.g. owl, mice, koala
NOCTURNAL
Long-term torpor (can be 6 months) occurring in the
summer months (ectotherms)
* To avoid damage from high temperatures
(desiccation- extreme dryness or drying out)
Estivation
_________ – active during daytime
e.g. “grazers” – gazelles, elephants
DIURNAL
_________ _______ zone represents ambient
conditions where heat gain by animal equals
heat loss (= thermal comfort; 28-31 degrees C in naked
humans)
Thermo neutral
‘COOLING OFF’ TECHNIQUES
* Rolling or wallowing in mud
* Taking a “dip” or standing in the water
* Going underground, using caves or lying in shade
* Flying in high altitudes
__________ – active at periods throughout 24-hours
e.g. some lemurs
CATHEMERAL
__________ – active at dawn & dusk
e.g. deer, rabbits, most birds, red pandas, cats
CREPUSCULAR
In humans about ____ percent of energy is
used for body heat.
50
Body temperature balance is very narrow range, usually higher/lower
than environment.
higher
___________ - body temperature too high
Fever: pyrogens fight pathogens
Heat exhaustion (102 F/38.8C)
Heat stroke (106F/41C) → death
Malignant hyperthermia – defective Ca++ release
HYPERTHERMIA
__________ - body temperature too low
Metabolism slows → loss of consciousness, death
Surgical applications: heart surgery
HYPOTHERMIA
Humans eat more than needed. Human eating is influenced by learned & unlearned mechanisms. True/False
True
Factors influencing human eating:
- Biological (hormones)
- Psychological (mood, sight and smell of food)
- Socio-cultural (norms about weight, cultural foods)
Function of _________ system is to break food down
into smaller molecules that cells can use.
digestive
_________ is the body’s main ‘fuel’
Glucose
After weaning most mammals lose intestinal enzyme _______ which is
needed for metabolising lactose (sugar in milk)
lactase
(2/3 of humans lack lactase)
The _________ controls eating & other body
maintenance functions
hypothalamus
THE _______ HYPOTHALAMUS CONTROLS:
* Insulin secretion
* Alters taste responsiveness
lateral
Electrical stimulation to lateral hypothalamus in increased/decreased appetite.
Increased
Damage to lateral hypothalamus can result in starvation due to food and water refusal. True/False
True
__________ HYPOTHALAMUS:
* Tumors lead to overeating & weight gain
* Alters taste responsiveness
VENTROMEDIAL
Damage to areas in or around the ventromedial
hypothalamus:
* Animal has increased appetite, gains lot of
weight, then becomes ‘finicky’ eater
* Eat normal meals more often (overeat)
Damage to paraventricular nucleus of hypothalamus:
* Animal eats larger meals (overeats)
________ monitors appetite hormone levels
Hypothalamus
______ nervosa (considered psychiatric condition)
* Unwilling to eat as much as they need; become extremely
thin & may die
ANOREXIA
________ NERVOSA (considered psychiatric condition)
* Alternate between extreme dieting and binges of
overeating
BULIMIA
‘SETTLING POINT’: cluster of genetic &
environmental factors cause a person’s weight to
settle within a given range
* Children more likely to be obese if parents are
obese
* Weight can be affected by diet, exercise, daily
habits (e.g., use stairs instead of lift)
The Hypothalamus controls eating and other body maintenance functions - what does the Lateral Hypothalamus control?
a) Insulin secretion
b) Creates tumours
c) Alters taste responses
d) Controls weight gain
a and c
The WHO research also shows that genetics does NOT play a role in determining body weight. True/False
False
The WHO commission studied childhood obesity - they found that there were no personality trait differences between obese and non-obese people. True/False
true
The Hypothalamus monitors appetite and hormone levels - which of the below are appetite hormones?
a) Leptin
b)Dopamine
c) Pectin
d) Insulin
leptin and insulin
What other factors besides biological ones, influence hunger and eating?
Memories of last meal
Food trends
Colour of the food
Taste preferences
How much you ate yesterday
Memories of last meal
Food trends
Taste preferences
Most obese people produce plenty of leptin & have
normal leptin receptors, so they overeat for other
reasons
- Fat cells throughout body produce peptide
leptin (more fat cells, more leptin) - Mice with ‘obese’ gene do not make leptin
- Gene exists that increases eating, decreases
metabolic rate & increases weight gain
obesity & inactivity are 2 largest contributors to
developing heart disease – Australia’s biggest
killer
≈ 55,000 people die from heart disease each year
(1 every 12 minutes)
Dieters and obese are more likely to eat in
response to stress than non-dieters
* Family environment of little importance in
determining body weight - genetics plays a large
role
___ ______ _______ (BMI) Measure of relative size based on mass & height
body mass index
BMI ____ or below is ideal, ____ or more is obesity.
25, 30
