Endocrine system Flashcards
What are the three mechanisms of intercellular communication?
Paracrine, Autocrine, Endocrine
What does the amount of hormone in the blood depend on?
The rate of hormone secretion and rate of removal from blood
What do beta cells secrete?
Insulin
What do alpha cells secrete?
Glucagon
Where are alpha and beta cells found?
The pancreas
What does insulin do?
When insulin is secreted into the blood stream it causes the liver and muscles to uptake glucose, therefore decrease the blood glucose concentration
What does glucagon do?
Targets the liver cell to breakdown glycogen (stored form of glucose) and synthesis more glucose and ketone to increase the blood glucose concentration
What is hyper and hypo secretion?
When there is too much or too little hormone being produced
What is hypo and hyper sensitivity
When hormone receptors respond too much or have little / no response
What is type 1 diabetes?
Hypo-secretion: too little or no insulin is secreted so glucose levels are very high in someone who has this
What is type 2 diabetes
hyposensitive: too little or no response to insulin from the receptor
What are some outcomes of diabetes
Glucosuria, polyuria, polydipsia, disrupted blood flow, diabetic neuropathy
Where is the pituitary gland located?`
At the base of the brain and is attached to the hypothalamus
How is the pituitary gland activated?
When the hypothalamus receives neural input it will stimulate the pituitary gland to secrete hormones
What are some anatomical features of the posterior lobe of the pituitary gland?
It is connected to the hypothalamus by neurons, the cells bodies in the hypothalamus and axons terminate in the posterior lobe. And secretes hormones into the blood.
Where are posterior pituitary hormones produced and stored?
They are made in the cell body of the neuron in the hypothalamus, travel down the axon and are stored there until required
What two hormones are released by the posterior pituitary gland?
Antidiuretic hormone and oxytocin
What is antidiuretic hormone?
It is a hormone that stimulates the kidneys to reabsorb water
What is oxytocin
It stimulates the contraction of uterine muscles during childbirth and stimulates milk release in breastfeeding
Describe the anatomical features of the anterior lobe of the pituitary gland
It is connected to the hypothalamus by blood vessels. with nerual input within the hypothalamus, Hypothalamic hormones stimulate or inhibit release of stored hormones from specific cells
How is growth hormone secreted?
Via a negative feedback system, the hypothalamus will secrete GH-RH which causes the anterior pituitary gland to secrete growth hormone.
What are the indirect effects of growth hormone?
Promotes the growth of bones, muscle and other tissues by causing release of somatomedin C which promotes cell division.
