Physiological adaptations
Homeostasis: The body's ability to maintain a relatively stable environment.

Internal environment: Tissue fluid, interstitial fluid.
External environment: Our surroundings.

Internal aspects of the body that need to be maintained at a steady state=

Blood glucose levels, temperature, blood pressure, insulin, cholesterol, pH, ions/salts, red & white blood cells, water.

The somatic nervous system:

*Controls skeletal muscles (movement)
*Instructions generally originate from the primary motor cortex of the brain.
*Controls voluntary movements.

Sensory neuron:
-Afferent neuron
-Detect stimuli and transmit to the CNS.
Inter neuron:
-Connecting neuron
-Transmits signal to motor neurons/ other parts of the CNS

Human endocrine system:
~Uses chemical substances called hormones to send messages all around the body.
~In response to a signal, hormones are released by specialised groups of cells called 'endocrine glands'.

Nervous system:
*Mode of transmission= Electrical and chemical
*Speed= Fast
*Travel to target= Direct via nerves
*Energy expenditure= High
*Duration of effect= Short

Afferent:
Afferent or sensory neurons receive information from the outside (sensory receptors) and sends them to other neurons so the body can produce a response.

Stimulus response system:
~Model of how a stimulus cases a change in the state or activity of a cell or organism (response).
~The system results in a changing of the stimulus effect.
~Stimulus may be internal or external.

~Our body's core temperature= 37*
~Our bodies heat comes from= Internal reactions, metabolism.
~Our body can detect temperature changes via= Thermoreceptors (Hot & cold receptors); Skin, internal (Blood vessels).

Too cool down:
~Reduce the amount of heat generation.
~Increase the amount of heat loss.
-->Behavioural: Remove clothing, spread out.
--> Sweating: Evaporation increases.

To warm up we can:
~Increase the amount of heat generated.
~Reduce the amount of heat lost.
--> Behavioural: Put on clothes, huddle, shiver (movement of muscles generates heat).

Control centre= Hypothalamus

ENDOTHERM: ~Mainly generates their own internal heat through metabolic reactions.
~Tend to have stable core body temperature.

Endotherms (Disadvantage):
~Energy intensive

~Need to eat to provide fuel to warm our body.

Endotherms (EXAMPLES):
~Eat a lot of food
~Metabolic processes
~Rely on panting to increase evaporation due to fur
~Avoid overheating