Endocrine System Flashcards
What are endocrine cells?
Hormone-secreting cells
What are endocrine glands?
Hormone-secreting organs
How are the endocrine and nervous system related?
They are structurally, chemically and functionally related.
- Neurosecretory cells secrete hormones into the blood
- Chemical such as epinephrine serve as both hormones of the endocrine system and signals in the nervous system
- Feedback regulation is a feature of both the endocrine and nervous systems
What are growth factors?
Proteins and polypeptides that stimulate cell proliferation
What are the 3 types of growth factors and what are their functions?
- Nerve growth factor (NGF) affects certain embryonic cells, developing white blood cells and other kinds of cells
- Nitric oxide (NO): gas that when secreted by neurons act as a neurotransmitter
When secreted by white blood cells, it kills bacteria and cancer cells
When secreted by endothelial cells, it dilates the walls of blood vessels - Prostaglandins (PGs) are modified fatty acids that are secreted by the placenta to stimulate uterine contractions during child birth
Chemical classes of hormones and function in vertebrates?
- Polypeptides
- Amines derived from a.a
- Steroids
SOLUBILTy
-water-soluble hormone = receptor on outside of target cells
-lipid soluble = inside target cells
What is an advantage of the signal-transduction pathways?
Allow for small amounts of a hormone to have a large effect
What usually happens when intracellular receptors are activated by a hormone?
They become a transcription factor
What are tropic hormones and what is their function?
Tropic hormones are hormones that target other endocrine glands and are important to understanding chemical coordination
(target other endocrine glands that in turn release their own hormones : dominoes)
What is the posterior pituitary and what is its function?
The posterior pituitary gland stores and secretes hormones secreted by the hypothalamus
- Oxytocin is a peptide that stimulates the contraction of the uterus and mammary glands. Secretion regulated by the nervous system
- Antidiuretic hormone (ADH): a peptide that promotes water retention by the kidneys. Secretion regulated by water/salt balance
What are growth hormones and what is their function? (hormone secreted by anterior pituitary)
Growth hormones (GH) are proteins that stimulate growth and metabolism. Acts directly on tissues or acts via growth factors
- Gigantism: excessive GH during development
- Acromegaly: excessive GH production during adulthood
- Hypopituitary dwarfism: childhood GH deficiency
What is Prolactin (PRL) and what is its function? (hormone secreted by anterior pituitary)
Prolactin is a protein that stimulates milk production and secretion
What are the different types of Gonadotropins? (hormone secreted by anterior pituitary)
Glycoproteins
- Follicule-stimulating hormone (FSH): stimulates production of sperm and ova
- Luteinizing hormone (LH) stimulates ovaries and testes
What is Thyroid-stimulating hormone (TSH) and function? (hormone secreted by anterior pituitary)
Glycoprotein that stimulates the thyroid gland
Secretion regulated by thyroxine in the blood and hypothalmic hormones
What is Adrenocorticotropic hormone and function? (hormone secreted by anterior pituitary)
Peptide that stimulates the adrenal cortex secrtion of glucocorticoids. Secretion regulated by glucocorticoids and hypothalmic hormones
