Endocrine system and female reproduction Flashcards
What is the function of endocrine glands
secrete products called hormones and release them into the adjacent tissue spaces
What are the three classes of hormones (give exampe)
- Proteins, polypeptides, and peptides (GnRH,FSH) 2. Amines (epinephrine) 3. Steroids (androgens like testosterone)
What class do androgens belong to
steroids
What is a ligand
A molecule that binds to a specific receptor on another molecule, often triggering a cellular response by delivering a signal.
True or False: Receptors for steroid hormones are located within the cytoplasm or nucleus of target cells
true
True or False: the half life of a peptide hormone is hours compared to a steroid hormone which is minutes
false
What is the function of a sex steroid binding globulin
it binds to sex hormones like testosterone and estrogen in the bloodstream, effectively regulating the amount of these hormones that are actively available to target tissues by controlling their access to cells
True or False: Each hormone has its unique receptor, resulting in equal numbers of hormone and receptor types
false
What is weak versus strong affinity of a hormone to a receptor? Give an example
of a hormone
A weak affinity means the hormone binds poorly while a strong binds well. Estradiol has a strong affinity while estrone and estriol are weak.
What is an agonist and antagonist
An agonist mimics while antagonist block
Which hormones would a GnRH Antagonist and a GnRH Inhibitory Agonist affect and why is it important in terms of fertility?
It lowers gonadal steroids (reduces estrogen). This is a potential contraceptive and prevents premature ovulation.
Which is medically useful for the ability to
shut down gonadotropins and, thus, lower gonadal steroids and inhibit egg and
sperm maturation
GnRH inhibitory agonists and GnRH antagonist
What is the function of the pituitary gland
It synthesizes and secretes hormones that travel in the bloodstream and influence many aspects of our body like other endocrine glands. If removed, reproductive system doesn’t function
What is the name of the two lobes in the pituitary gland
Adenohypophysis and Neurohypophysis
What kind of nerve cells secrete hormones and how does this differ from the most common one
Neurosecretory cells. It differs from neurons because it releases hormones directly in the bloodstream.
Neurohormones are secreted from neurons that originate from where
The hypothalamus
Which hormones do neurosecretory neurons secrete and what is the function of
each hormone?
Oxytocin and Vasopressin. Oxytocin causes contractions and facilitates milk. Vasopressin causes kidneys to retain water and and raises blood pressure
Where is the GnRH Pulse Generator located and why is its function important to
fertility?
In the hypothalamus. It controls the menstrual cycle
True or False: GnRH regulates the release of FSH and LH and these two hormones control
gamete production and hormone release from the gonads (testes/ovaries).
True
Would an increase in FSH and LH lead to a gain or loss in fertility and WHY?
It would lead a loss in fertility because it causes fewer eggs that are able to mature
What is happening with sex steroids in the Luteal Phase of the menstrual cycle
versus in a combination contraceptive pill? What is the ultimate result of the
activity of these sex steroids?
Both cause a negative feedback cycle. In the luteal phase, GnRH is inhibited and decreases FSH and LH which prevents ovulation. Combination pills do this too. The ultimate result is ovulation being stopped.
Releasing Hormone
Neurohormone that increases output of a particular adenohypophysial hormone
Growth Hormone
Stimulates tissue growth
LH
induces release of egg from ovary