The Endocrine System

These flashcards cover key terms and concepts related to the endocrine system, including definitions and descriptions of specific hormones, glands, and regulatory mechanisms.

Endocrine System

A system of glands that secrete hormones into the bloodstream to regulate various bodily functions.

Hormones

Chemical messengers produced by glands in the endocrine system that regulate processes in the body.

Lipid-Soluble Hormones

Hormones that can diffuse across plasma membranes and bind to intracellular receptors.

Water-Soluble Hormones

Hormones that circulate freely in the bloodstream and bind to receptors on the surface of target cells.

Negative Feedback

A mechanism by which the body maintains homeostasis; the output of a system acts to reduce or dampen the processes leading to the output.

Positive Feedback

A process that increases the output of a system, often leading to a greater change in the same direction.

Hypothalamus

A brain region that links the nervous system to the endocrine system and regulates the pituitary gland.

Pituitary Gland

Often referred to as the master gland, it controls and regulates other endocrine glands.

Thyroid Gland

An endocrine gland that produces hormones that regulate metabolism and affect growth and development.

Parathyroid Gland

Glands that regulate calcium levels in the blood by secreting parathyroid hormone (PTH).

Adrenal Glands

Glands located on top of the kidneys that produce hormones such as cortisol, adrenaline, and aldosterone.

Insulin

A hormone produced by the pancreas that regulates blood glucose levels by facilitating cellular glucose uptake.

Glucagon

A hormone secreted by the pancreas that raises blood glucose levels by promoting glycogen breakdown.

Melatonin

A hormone produced by the pineal gland that regulates sleep-wake cycles and circadian rhythms.

Cortisol

A glucocorticoid hormone produced by the adrenal glands in response to stress, which regulates metabolism and immune responses.

Endocrine Disorders

Medical conditions characterized by abnormal hormone levels, such as diabetes and thyroid disorders.

Endocrine Disruptors

Environmental chemicals that can interfere with hormone production, release, or action.

When blood glucose levels are too low, _______, in the pancreatic islets secrete ________

alpha cells, glucagon

When blood glucose levels are too high, _______, in the pancreatic islets secrete ________

beta cells, insulin

low blood calcium levels

What stimulates the parathyroid glands to release parathyroid hormone (PTH)

aldosterone

What hormone is secreted by the zona glomerulosa of the adrenal cortex?

HPA

Controls stress response

HPT

Metabolism

HPG

Reproduction

HPS

Growthand development hormone signaling pathway.

True

The posterior pituitary gland (neurohypophysis) does not make its own hormones.

melatonin

The pineal gland primarily secretes which hormone?

hyperthyroidism

Which type of disorder is associated with overproduction of thyroid hormones?

A collection of glands that secrete hormones into the bloodstream to regulate body functions

Which of the following best describes the endocrine system?

excessive thirst and frequent urination

Which of the following is a symptom of diabetes mellitus?

Exposure to endocrine-disrupting chemicals (EDCs) may:

Cortisol

What hormone is primarily released during stress to raise blood glucose levels?

hypothyroidism

Which type of disorder is associated with underproduction of thyroid hormones?

Target cells up-regulate receptors to increase sensitivity

What happens when hormone levels are chronically low?

Releases hormones made by the hypothalamus

Posterior Pituitary

Synthesizes and secretes hormones

Anterior Pituitary

Exposure to endocrine-disrupting chemicals (EDCs) may: 

Water-soluble

hormones activate a signaling cascade using secondary messengers

True

The posterior pituitary gland (neurohypophysis) does not make its own hormones.

Bloodstream

After production, most hormones are secreted into which part of the body?

consistent exercise and a balanced diet

Which of the following behaviors is most likely to support healthy endocrine function?

antagonistic

Two hormones oppose each other’s effects or downregulate each other’s receptors. These hormones are ___ to one another.

Permissive

One hormone is required for another to have its full effect

Antagonistic

Two hormones oppose each other’s effects or downregulate each other’s receptors

Synergistic

Two hormones amplify each other’s effects on the same pathway and work together to enhance their physiological impact.

aldosterone

What hormone is secreted by the zona glomerulosa of the adrenal cortex?

It amplifies the original stimulus

What is the effect of positive feedback on hormone secretion?

Water-Soluble

Binds to receptors on the cell surface

Steroid hormone

Made from cholesterol 

Lipid-Soluble

Can pass through the cell membrane and bind to intracellular receptors.

Lowering blood calcium levels by promoting calcium excretion

Which of the following is not a function of parathyroid hormone (PTH)?

Hormonal regulation of body functions

Which of the following best describes the primary function of the endocrine system?

Alpha Cells

Which pancreatic cells produce glucagon?

Growth Hormone (GH)

Which of the following hormones is secreted by the anterior pituitary?

Anterior

The_______ pituitary gland is regulated by releasing hormones from the hypothalamus via the hypophyseal portal system.

Calcitonin

Which thyroid hormone lowers blood calcium levels?

lower blood glucose levels

What is the main function of insulin?

The thymus

Which of the following endocrine organs is involved in immune function

The Pancreas

Which of the following endocrine organs is involved in blood sugar regulation

The kidneys and parathyroid glands

Which two endocrine organs are involved in calcium regulation