Integument Physiology Flashcards
What are 7 functions of the integument?
Protection, Immune defence, sensing environment, Thermoregulation, Storage and excretion, Communication and Selective Permeability
What is a mechanoreceptor?
detects stimuli from external environmnent such as touch, sound, pressure and vibration
Ruffinis end organ
detects stretches in the skin
Krauses end bulb
Cold stretches in the skin
Meissners corpuscle
pressure, fast vibration
Merkels disc
free nerve ending- sustained touch and pressure
Nociceptors
Free nerve endings- pain receptors
Thermoreceptors
Free nerve endings- Temperature
Homeostasis
Maintenance of constant internal conditions within the bodys internal environment
Hypothalamus
controls activities of autonomic nervous system, controls a major part of the endocrine system
Below 34 degrees…
animals unable to regulate their own temperature
At 27 to 29 degrees…
cardiac fibrillation and death
increase of temperature to 45 degrees…
can cause fatal lesions
Hypothermia
when heat loss exceeds heat production
Hyperthermia
above normal body temperature, heat production exceeds heat loss
Fever/Pyrexia
reset of hypothalamic set point to higher temperature
Muscle contraction (shivering thermogenesis)
means of increasing metabolic heat by contracting muscles
Brown adipose tissue (non-shivering thermogenesis)
special type of body fat that gets activated when they get cold
Brown adipose tissue is…
predominantly in neonates, darker in colour, present in small hibernating mammals, smaller numerous lipid droplets
Where is brown adipose tissue located?
subcutaneous region between scapulae and around kidneys and myocardium
What is usually found close to brown adipose tissue?
many mitochondria as they facilitate rapid transfer of stored energy into heat energy
What are 4 physical ways animals can lose heat?
Radiation, Conduction and Convection and evaporation
