30 Questions
Which type of hormone can easily pass through the phospholipid plasma membrane of target cells?
Steroids
Which hormone is an example of a peptide?
Insulin
Which of the following is a function of hormones?
All of the above
Which hormone is an example of a glycoprotein?
Thyroid stimulating hormone
Which type of hormone interacts with receptor sites on the cell surface?
Non-steroids
Which hormone is an example of an amino acid derivative?
Epinephrine
Which hormone is classified as a protein?
Insulin
What is the main function of the endocrine system?
To regulate the body's internal environment through the release of hormones
What is the main difference between the nervous system and the endocrine system?
The nervous system has direct effects and a faster response time, while the endocrine system has indirect effects and a slower response time
What is the purpose of signal transduction pathways in the endocrine system?
To detect, amplify, and integrate external signals to generate cellular responses
What is the role of hormones in the endocrine system?
Hormones are chemical messengers that have an effect on target cells distant from the hormone-secreting cells
How do the endocrine and nervous systems work together?
The endocrine system complements the nervous system, but they are very different in their mechanisms of action
How are physiological levels of hormones maintained in the body?
When hormone levels are low, the glands produce and release more hormones, and when levels are high, the glands stop producing and releasing hormones
How are hormones measured in the body?
Hormones are measured by analyzing their concentration in the bloodstream
Which hormone is produced by the pineal gland?
Melatonin
Which endocrine gland is located between the lungs?
Thymus gland
What is the function of the hypothalamus?
Links the central nervous system and endocrine system
Which hormone is classified as an iodinated amino acid?
Triiodothyronine (T3)
Where are the adrenal glands located?
On top of the kidneys
Which hormone is classified as a glycoprotein?
Follicle-stimulating hormone (FSH)
Which hormone is classified as an amine?
Norepinephrine
Which hormone is responsible for milk production?
Prolactin
What is the primary role of the parathyroid hormone (PTH)?
Increasing calcium levels in the blood
Which part of the adrenal gland is responsible for producing steroid hormones?
Adrenal cortex
What is the role of the thymus gland?
Developing and maturing T-cells
What is the function of the posterior pituitary gland?
Storing and releasing hormones produced by the hypothalamus
What is the primary role of insulin and glucagon?
Maintaining blood glucose levels
Which hormone is responsible for stimulating the ovaries to produce estrogen?
Luteinizing hormone (LH)
What is the role of the hypothalamus in the endocrine system?
It controls the release of hormones from the pituitary gland
What is the primary function of the adrenal medulla?
Releasing neurotransmitters for the sympathetic nervous system
Study Notes
Introduction to Endocrinology
- The endocrine system regulates the body's internal environment via endocrine glands, which produce and release hormones.
- Hormones are released into the bloodstream, transported to distant parts of the body, and bind to target cells to elicit effects.
Characteristics of Hormones
- Hormones are chemical messengers that have an effect on target cells distant from the hormone-secreting cells.
- Signal transduction pathways mediate the sensing and processing of external stimuli.
- Steps in signal transduction: a stimulus arrives at an endocrine gland, inducing a secretory cell to release a signaling molecule (hormone), which binds to a receptor on a target cell's plasma membrane, initiating a signaling cascade inside the cell.
Classification of Hormones
- Classified based on composition and where they interact with target cells.
- 2 main types: steroids (cholesterol-derived, lipid-soluble, easily pass through phospholipid plasma membrane of target cells) and non-steroids (protein-derived, water-soluble, interact with receptor sites on the cell surface).
Non-Steroid Hormones
- Proteins: made of long chains of amino acids (e.g., insulin and glucagon).
- Glycoproteins: attached to a carbohydrate group that attaches to an amino acid (e.g., thyroid-stimulating hormone).
- Peptides: short chains of amino acids (e.g., oxytocin).
- Amino acid derivatives: single amino acids (e.g., epinephrine, norepinephrine, melatonin).
Endocrine Glands
- Produce and excrete hormones, working together to achieve a response.
- Locations: brain, neck, lungs, pancreas, kidney, pelvic region.
Hypothalamus and Pituitary Gland
- Hypothalamus: "control center" linking the CNS and endocrine system.
- Senses impulses from the brain and passes them to the pituitary gland.
- Pituitary gland: "master gland" that controls other endocrine glands by activating their release of hormones.
- Divided into two sections: anterior (communicates with hypothalamus via hormone) and posterior (communicates with hypothalamus via neurons).
Thyroid and Parathyroid Glands
- Thyroid gland: produces thyroid hormones (T3 and T4) that regulate metabolism, development, and catecholamine release.
- Parathyroid glands: produce parathyroid hormone (PTH), which maintains calcium homeostasis and opposes calcitonin's activity.
Adrenal Glands
- Located on top of the kidneys.
- Adrenal cortex (shell): produces steroids, including cortisol, which increases blood glucose and suppresses the immune system, and aldosterone, which increases sodium reabsorption in the blood and maintains hydration.
- Adrenal medulla (core): produces neurotransmitters for the sympathetic nervous system, including norepinephrine and epinephrine.
Ovaries and Testes
- Produce sex hormones (estrogen and progesterone in ovaries, testosterone in testes) that regulate reproductive processes.
- FSH stimulates follicle and egg maturation in ovaries, and sperm production in testes.
- LH stimulates ovulation and progesterone production in ovaries, and testosterone production in testes.
Learn about the endocrine system, which regulates the body's internal environment through the production and release of hormones. Explore how hormones are transported in the bloodstream to target organs to elicit specific effects. Compare the endocrine system with the nervous system and understand their differences.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
