The Endocrine System: The Hypothalamus & Pituitary Gland

These flashcards cover key terms and concepts related to the hypothalamus and pituitary gland as part of the endocrine system.

What is the function of the endocrine system in relation to the nervous system?

It works with the nervous system to maintain homeostasis.

What are the basic units of the endocrine system?

Endocrine glands (ductless glands).

What do endocrine glands produce and secrete?

They produce and secrete hormones.

What are chemical messengers produced by endocrine glands called?

Hormones.

Where are hormones secreted?

Directly into the bloodstream.

What happens when hormones find their specific receptors?

They produce effects.

What is a target cell?

A cell that has receptors for a particular hormone.

What are the two types of feedback systems in the endocrine system?

Negative and Positive feedback.

What can trigger the secretion of some hormones?

Direct stimulation from the nervous system.

What is an example of a chemical that stimulates hormone release from the pancreas?

Glucose.

How does negative feedback work in the endocrine system?

Increased plasma hormones cause the hypothalamus to decrease releasing factors, which decreases trophic hormone from the Pituitary Gland, leading to decreased target organ activity and plasma hormones.

What is an example of a less common feedback mechanism?

Oxytocin release in response to nursing.

Which gland is known as the master endocrine gland?

Pituitary gland.

What are the two parts of the pituitary gland?

Anterior pituitary (adenohypophysis) and posterior pituitary (neurohypophysis).

What does the hypothalamus control?

Activities of the pituitary gland.

How do modified neurons in the hypothalamus communicate with the anterior pituitary?

By secreting releasing and inhibiting factors into a portal system.

Where are ADH and oxytocin transported after being produced by the hypothalamus?

To the posterior pituitary.

What triggers the release of hormones from the posterior pituitary?

Nerve impulses from the hypothalamus.

What is the role of growth hormone (GH)?

Promotes growth and regulates energy use in adults.

What condition is caused by GH deficiency?

Dwarfism.

What does the hormone prolactin do?

Helps initiate and maintain lactation.

What stimulates the thyroid gland to produce hormones?

Thyroid-stimulating hormone (TSH).

What does adrenocorticotropin hormone (ACTH) stimulate?

Growth and development of adrenal glands.

How does follicle-stimulating hormone (FSH) affect females?

Stimulates growth and development of ovarian follicles and estrogen production.

What is the role of luteinizing hormone (LH) in females?

Completes follicle development and stimulates ovulation.

What stimulates the testes in males?

Luteinizing hormone (LH) stimulates testosterone production.

What is the function of antidiuretic hormone (ADH)?

Helps prevent diuresis by reabsorbing water in the kidneys.

What happens when there is a deficiency of ADH?

It causes diabetes insipidus.

What role does oxytocin play during parturition?

It causes contractions of the uterus to help with delivery.

What is the impact of high estrogen levels on FSH?

High levels of estrogen lead to decreased FSH due to negative feedback.

How does oxytocin affect milk letdown?

It stimulates milk letdown in the mammary glands.

What triggers the release of prolactin?

Stimulation of the teat by nursing or milking.

What type of hormones does the anterior pituitary secrete?

Trophic hormones that regulate other glands.

What is a key function of the hypothalamic-pituitary axis?

Regulates the endocrine system in response to stimuli.

Which hormones are stored in the posterior pituitary?

ADH and oxytocin.

What is the feedback mechanism of ACTH?

Regulated by negative feedback from adrenal hormones.

What hormone is known as somatotropin?

Growth hormone (GH).

What does the hypothalamus do in response to environmental stimuli or stress?

It communicates with the pituitary gland.

What hormone is released during stress responses?

Adrenocorticotropin hormone (ACTH).

How does the hypothalamus regulate body temperature?

Through its functions, including appetite control and wake-sleep cycles.

What is released during suckling that promotes milk production?

Oxytocin.

What happens to FSH right before ovulation?

It decreases due to negative feedback, while LH increases.

Why is the pituitary gland often called the master gland?

It directs the activity of other endocrine glands.

What does the hypothalamus release to stimulate the anterior pituitary?

Releasing factors.

Which gland is responsible for regulating metabolism through hormone production?

Thyroid gland.

What condition arises due to excessive thirst and urination linked to ADH deficiency?

Diabetes insipidus.

What is the primary role of the corpus luteum after ovulation?

To produce progesterone necessary for pregnancy.

How does the hypothalamus function as a bridge?

It connects the nervous and endocrine systems.