The Endocrine System - Glands and Hormones

Question-and-answer flashcards covering key concepts of the endocrine system and its interaction with the nervous system.

What is the primary role of the endocrine system in relation to the nervous system?

To work with the nervous system to control vital body functions by releasing hormones into the bloodstream.

How do hormones reach their target cells and what must those cells have?

They are secreted into the bloodstream and affect cells that have receptors for that hormone.

Which gland produces the hormone thyroxine?

The thyroid gland.

What effect does thyroxine have on the heart?

It increases heart rate.

What effect does thyroxine have on the body's metabolic rate?

It increases metabolic rate (chemical processes in cells).

What is the 'master gland' of the endocrine system?

The pituitary gland.

Where is the pituitary gland located?

In the brain.

Why is the pituitary gland often called the master gland?

Because it controls the release of hormones from all the other endocrine glands.

During stress, which brain structure initiates a cascade that activates the sympathetic branch of the ANS?

The hypothalamus, which activates the pituitary and triggers the sympathetic ANS.

Which hormone is released from the adrenal medulla during the stress response?

Adrenaline.

Where is the adrenal medulla located?

Within the adrenal gland lying near the kidneys.

What are the immediate physiological changes caused by adrenaline?

Increased heart rate and other arousal changes that prepare the body for fight or flight.

What does the term 'fight or flight' describe?

The body's rapid, automatic response to a threat, involving physiological arousal.

What happens to the autonomic nervous system after the threat passes?

The parasympathetic nervous system returns the body to its resting state.

How do the sympathetic and parasympathetic systems relate to each other?

They are antagonistic; the parasympathetic system acts as a brake on the sympathetic system.

Name the main endocrine glands shown in the body diagram.

Adrenals, Pancreas, Ovaries, and Testes.

How are hormones transported to target organs?

Via the bloodstream.

Define endocrine gland.

An organ that synthesizes substances such as hormones.

Define a hormone.

A biochemical substance that circulates in the blood and affects target organs; produced in large quantities but disappears quickly.

What does a cell need to be affected by a specific hormone?

A receptor for that hormone on or in the cell.

What is the endocrine system's method of communication?

Chemical communication through hormones in the bloodstream.

What happens when the hypothalamus activates the pituitary during stress?

It triggers activity in the sympathetic branch of the ANS.

During stress, what triggers the sympathetic branch of the ANS?

Activation of the hypothalamus and pituitary.

Which hormone is part of the body's immediate stress response?

Adrenaline.

What effect does adrenaline have on the air passages?

It dilates the air passages.

What cardiovascular effects are caused by adrenaline?

Increases heart rate and affects blood vessel dynamics as part of the fight-or-flight response.

How does the endocrine system differ from the nervous system in speed and reach?

Endocrine effects are slower to start but widespread and powerful; the nervous system acts quickly and locally.

What growth-related influence does thyroid hormone have besides metabolism?

It affects growth rates throughout the body.

Which part of the adrenal gland releases adrenaline?

The adrenal medulla.

What term describes the rest-and-digest state induced by the parasympathetic system?

Parasympathetic action or rest and digest response.

How quickly do sympathetic physiological changes occur after a threat is detected?

Almost instantaneously.