Fight or flight response

How does the dilation of pupils prepare the body for action?

Allows more light enter the us so a more detailed visual of the threat is seen.

Effect on smooth muscle

Alters blood flow. less blood flow to the gut/skin. It reduces gut secretions and relaxes muscle in the gut and peristalsis slows down. It relaxes in the air ways so airways are wider. Pupils dilate.

Effect on cardiac muscle

heart beats faster and it beats more forcefully.

How does making hairs stand up prepare the body for action

For some animals it makes them look bigger and more fierce. Intended to frighten off the attacker.

How does an increase in metabolic activity prepare the body for action?

Heightened level of activity require increases metabolic rate to metabolise all of the nutrients requires.

How doe an increase in sweat production prepare the body for action?

Increased metabolism generates heat which needs to be removed.

How does increasing ventilation rate and depth prepare the body for action?

Increased removal and CO2 and supply of O2.

How do the increase in heart rate and blood pressure, constriction of the arterioles to the digestive system and skin and the dilation of the arterioles to the liver and muscles prepare the body for action?

Increases the flow of blood around the body and directs blood to the muscles which may be called upon for explosive and sustained action.

Effect on voluntary muscle

Intercostal muscles contract faster. Muscles are being primed for action.

How do endorphins prepare the body for action?

Painkillers may be required in a situation where damage is possible.

How does increasing blood glucose levels prepare the body for action?

Supplies respiratory substrate to muscles for AT generation

Define the fight or flight response

The set of responses in an animal that accompany the perception of threat. The response is driven by the sympathetic nervous system and sets the body at a higher level of capacity to respond to threat.

Activation of the flight or fight response.

The sympathetic nervous system is stimulated. Noradrenaline is the neurotransmitter released at the neuromuscular junction. Adrenaline is secreted from the adrenal gland and binds to complementary receptors on target tissues.

Where is the fight or flight response trigger?

Triggered by the hypothalamus which activate the sympathetic nervous system.