Endocrine system overview

What is a gland?

A gland is one or more cells that makes and secretes an aqueous fluid.

How are glands classified?

Glands are classified by site of product release (endocrine or exocrine) and relative number of cells forming the gland (unicellular or multicellular).

What are exocrine glands?

Exocrine glands are ducted glands that secrete their products onto body surfaces or into body cavities.

Give examples of exocrine glands.

Examples include mucous, sweat, oil, and salivary glands.

What do endocrine glands do?

Endocrine glands are ductless glands that produce hormones and release them into the blood.

What types of molecules do endocrine glands release?

They release steroidal (lipid) or amino acid-like molecules.

How do hormones trigger changes in target cells?

Hormones trigger changes depending on whether they are water-soluble or lipid-soluble.

What is the role of the hypothalamus in the endocrine system?

The hypothalamus acts as the main control center of the endocrine system, responding to internal and external conditions.

What are the two posterior pituitary hormones and their functions?

ADH participates in osmoregulation; oxytocin stimulates uterine contractions during childbirth and milk release.

What is human growth hormone (HGH) and its effects?

HGH promotes development and enlargement of all body parts; too much leads to gigantism and too little leads to dwarfism.

What is the function of thyroid hormone?

Thyroid hormone affects metabolic rate, heart rate, blood pressure, tolerance to cold, and development and maturation of bone and nerve cells.

What is goiter and what causes it?

Goiter is caused by a lack of iodine, which is necessary for normal thyroid hormone synthesis.

What are the primary hormones produced by the pancreas?

The pancreas secretes insulin and glucagon to manage blood glucose levels.

What is diabetes mellitus?

Diabetes mellitus is a hormonal disease where body cells cannot absorb glucose from the blood.

What hormones do the gonads produce?

The gonads produce estrogen, progestins, and androgens.

What are the phases of the menstrual cycle?

The menstrual cycle consists of three phases: menstrual, proliferative, and secretory.

What can endocrine disruptors do?

Endocrine disruptors can affect reproductive function and alter the balance of sex hormones.

What is the role of tamoxifen in breast cancer treatment?

Tamoxifen inhibits estrogen binding to its receptors, which is effective in treating some breast cancers.

How do anabolic steroids function in the human body?

Anabolic steroids are artificial hormones similar to testosterone that may be used to treat hormonal decline.

What is the relationship between androgens and aggressive behavior in male elephant seals?

Androgens promote the development of large bodies and aggressive behaviors toward other males.