Endocrine System -13.2 Flashcards
(41 cards)
How many lobes does the pituitary gland have and what are they?
Anterior Pituitary and Posterior Pituitary
* It has two lobes
What connects the hypothalamus to the pituitary gland?
The pituitary stalk (infundibulum)
Why is the pituitary gland called the “master gland.”
It releases several trophic hormones - up to 8
What controls the pituitary gland?
The hypothalamus - via (releasing hormones and neurons through pituitary stalk)
Does the posterior pituitary produce hormones?
No, it is considered to be part of the nervous system - does not produce any hormones
- Releases and stores hormones (ADH and Oxytocin) that are produced in the hypothalamus - but are transferred through the neuronal axons
Does the anterior pituitary produce hormones?
Yes, it is a hormone synthesizing gland - produces up to 6 hormones
- hgh
- ACTH
- TSH
*FSH
*LH
*Prolactin
How is the anterior pituitary stimulated?
series of blood vessels (portal system) carries releasing hormones from hypothalamus to pituitary - hormones inhibit or stimulate the release of hormones from this gland
What does hGH released by the anterior pituitary do?
regulates growth, development, and metabolism
Cell division - bone and muscle growth
Is hGH a tropic hormone?
Yes, but it can have direct stimulation on some body tissue
What does hGH stimulate the liver to release?
growth factors
What physiological processes does hGH and growth factors affect?
- protein synthesis
*Cell division and growth - growth of cartilage, bone, and muscle
*Metabolic reaction and the release of fats stored in adipose tissue
What happens if large amounts of hGh is produced during childhood?
Gigantism
What happens if there is an insufficient production of hGH during childhood?
Dwarfism
What is acromegaly?
When someone reaches adulthood and skeletal growth is completed - and there is still an overproduction of hGH.
Can’t grow in height - bones and soft tissues widen
What caused Creutzfeldt - Jakob disease?
A child who received hGH treatment.
What did genetic engineering produce in 1985?
Synthetic hGH - gene that codes hGH is injected into bacteria - bacteria produces rapidly creating hGH
Describe the thyroid gland in regards to its location?
Located directly below larynx
Has two lobes - one on each side of the trachea
What is the primary affect of thyroxine (T4?)
To increase the rate at which the body metabolizes protein, fat, and carbohydrates for energy
Does thyroxine have a specific target organ?
No, it stimulates the cells of the heart, kidney, liver, and skeletal muscles to increase the rate of cellular respiration
Other than metabolism what other effects does thyroxine have?
It plays an important role in the growth and development of children - organizes various cells into the tissues and organs
What happens if thyroxine fails to develop properly in childhood?
Cretinism
What does an individual with cretinism look like?
They are stockier and shorter than the average child
Without hormonal injections early in life they will have developmental delays
What happens if there is an extremely low level of thyoxine produced?
Hypotyroidism
What happens to an adult with hypothyroidism?
*They feel tired
*Slow pulse rate and puffy skin
*Hair loss
*Gain weight
* Slow metabolism
