L8a+b. The Endocrine System (biopsych)

Endocrine System definition

A specialised system of tissues, mainly glands that works alongside the nervous system

Endocrine System - function

Regulates vital functions of the body by releasing hormones, mostly via the blood, to communicate messages to target organs.

What operates faster, the nervous system or the endocrine system

Nervous system

Do the endocrine system’s effects last longer than the nervous system’s?

Yes the effects are longer lasting

The Hypothalamus

Brain area in the base of the brain directly above the brain stem. Produces hormones that control the pituitary gland. It is the control centre in the brain that regulates the endocrine system.

Pituitary gland

known as the ‘master gland’ because it releases hormones to control other glands in the endocrine system (e.g. adrenocorticotropic hormone (ACTH) to stimulate adrenal glands), as well as LH and FSH

Cortisol

Stress response

Adrenaline and Noradrenaline

Fight or flight hormones

Thyroid gland - found where?

The neck

what does the thyroid gland produce

hormones such as thyroxine, which controls metabolism and growth

Parathyroid glands - located where?

Next to thyroid

What do Parathyroid glands produce

Hormones called parathyroid

What does parathyroid help us control

the levels of minerals such as calcium within the body

Pancreas

In the torso. Endocrine glands on the pancreas produce insulin and glucagon, which regulate the level of glucose in the blood

Pineal gland

In the centre of the brain. Produces melatonin which is the hormone that regulates the sleep/wake cycle (induces sleep)

Fight or Flight

response refers to the way an animal responds when stressed. The body becomes physiologically aroused in readiness to fight or flee from a threat

Fight or flight process

This response is a result of the nervous system and the endocrine system working together.

What does the short-term stress response involve?

involves the release of adrenaline

Short Term Stressors

When an individual is faced with an immediate threat, an area of the brain called the amygdala is mobilised. It sends a distress signal to the hypothalamus, which then directly activates the sympathetic branch of the ANS.

Fight or flight - threat passed

Once the threat has passed, the ANS returns to its resting parasympathetic state: rest and-digest

Fight or flight - effect

gets the body ready for action e.g. increased heart rate = more oxygen for energy

Examples of sympathetic state

Increased heart rate, increased breathing rate, dilated pupils, digestion inhibited and saliva production inhibited.

Examples of parasympathetic state

Decreased heart rate and breathing rate, pupils constricted, digestion stimulated, saliva production stimulated