Endocrine System Flashcards
What are the endocrine glands?
Hyptothalamus, pituitary gland, pineal gland, parathyroid gland, thyroid gland, adrenal gland, pancreas, ovary and testis.
What is the function of the endocrine system?
The endocrine system functions as one part of the body communicating with another part of the body to maintain homeostasis. The endocrine system uses hormones to carry messages. The endocrine system is much slower than the nervous system. Help regulate metabolic processes in the body.
What is Diabetes mellitus?
Diabetes mellitus is a problem with insulin in blood glucose regulation. It has two forms: type 1 and type 2.symptoms for both types are excessive thirst, excessive urine production, and glucose in the urine. If uncontrolled p, both types may lead to life-threatening complications.
What is diabetes insipdus?
Diabetes inspidus is a problem of insufficient ADH (Antiduratic hormone) secretion from the posterior pituitary. The symptoms are excessive thirst and excessive urine production.
What are growth disorders?
Growth disorders are a problem of GH (growth hormone) secretions from the anterior pituitary.
What are goitres?
Goitres can result from hyposecretion (slow secretion) or hypersecretion (fast secretion) of thyroid hormone (t3,t4).
Are endocrine glands with ducks or without ducks?
Duckless
How do hormones work?
Hormones are chemicals that travel through the body, but only have an effect in their bloodstream tissue(target tissue). The cells of tissue posses receptors only for specific hormones. Some hormones have multiple target tissues and others only have one.
What are the three mechanisms that hormone secretions are employed by negative feedback?
1) the nervous system can directly stimulate an endocrine gland?
2) the hypothalamus and anterior pituitary can simulate another endocrine gland. The hypothalamus monitors the hormone levels in the bloodstream secreted by a specific endocrine gland. If those levels deviate from their appropriate range, the hypothalamus either stimulates or inhibits the anterior pituitary gland. In response, the anterior pituitary gland secretes more or less hormone that controls the secretion of the original endocrine gland.
3) the internal environment can directly stimulate an endocrine gland. If the amount of a certain substance from it’s appropriate range, it will cause a specific endocrine gland to secrete more or less hormone.
Hormones secretions are controlled by?
Negative feedback systems
The nervous system is controlled by nerve impulses and it controls?
Muscles and glands
Effects caused by the nervous system are?
Rapidly and are of brief duration.
What is prolactin?
It is an anterior pituitary hormone that stimulates milk production.
What does the hypothalamus secret during stressful situations?
ACTH when the level of cortisol decreases.
What is the target tissue of FSH (follicle stimulating hormone)?
Ovaries and testes
Where is the control mechanism for FSH in females, and how is it stimulated?
The control mechanism is in the hypothalamus and it is stimulated when there is a decrease in the levels of estrogen and progesterone.
Luteinizing hormone (lh) stimulates what?
Ovulation in females
The excretion of LH in males is controlled by what and is a response in a change to?
The secretion of LH in make is regulated by the hypothalamus in response to changes in the testosterone concentration in the blood.
The three gonadotropin hormones are?
Prolactin, follicle stimulating hormone and lutenizing hormone.
What two hormones are produced by the hypothalamus and stored in the posterior lobe of the pituitary?
Oxytocin and antidiuretic hormone
The posterior pituitary will release antidiuretic hormone in response to nerve impulses from the ________________ which ensues a decrease in ________________.
Hypothalamus and blood pressure
What does oxytocin do?
Stimulates uterine contractions and milk release
What are the parathyroid glands?
There are four glands and they are located on the dorsal surface of the thyroid gland. They produce parathyroid hormone.
Parathyroid hormones acts on bone to stimulate osteoclast activity and inhibit ________ activity releasing ___________ from bone, which ___________ calcium levels in blood.
Osteoblasts, calcium, and increase
Parathyroid hormone acts on the small intestine to?
Absorb calcium which increases calcium levels in blood.
Parathyroid hormone acts on the kidneys to conserve what?
Calcium which increases calcium in the blood.
What two hormones control calcium levels in the blood?
Calcitonin and parathyroid hormone
What does blood glucose levels control of the secretion of?
Insulin and glucagon from the pancreas.
The _____________________ are specialized cells in the pancreas that secrete the hormones insulin and glucagon.
Pancreatic islets
Insulin is secreted by what cells of the pancreatic islets?
Beta
Insulin allows most body cells to take in glucose by promoting the process of _____________ diffusion?
Facilated
Insulin causes the __________ to change glucose to glycogen for storage?
Liver
Glucagon is produced by what cells in the pancreatic islets?
Alpha
Glucagon is secreted into the bloodstream when?
A decrease in the blood glucose level
Where are the adrenal glands located?
On top of the kidneys, they consist of a outer cortex and inner medulla.
What groups of hormones are produced by the adrenal cortext?
Mineralocortioids
Glucocorticoids
Androgens
Name a major mineralocorticoid?
Aldosterone, targets kidney, stimulates kidney to reabsorb sodium & water, secrete potassium. (decrease in blood pressure, decrease in sodium levels, and increase in potassium)
What is a major glucorticoid?
Cortisol, which functions to stimulate the breakdown of lipids & proteins, increase the amount of amino acids in blood, Which promotes an increase in glucose levels in the blood.
Hypothalamus = Anterior pituitary - adrenocorticotropic hormone (ACTH), in times of stress, decrease in cortisol levels.
what is testosterone?
Major androgen, adrenal cortex production is minimal.
What hormones are produced by the adrenal medulla?
Epinephrine - which is similar to the sympathetic nervous system, but lasts longer.
Effects of epinephrines?
Heart rate - Increases Bronchioles - Dilates Digestive Organs - Relax Digestive glands - Decrease secretions Liver - Increases (Blood glucose levels) Blood Vessles (Skin organs) - Decreases blood flow Blood vessles to (skeletel muslces) - Increases Brain - increase Alterness Metabolic rate - increases
How is the production of epinephrine stimulated?
By the sympathetic nervous ssytem & Controlled by nerve impulses from the hypothalamus.
During puberty, testosterone stimulates the enlargement of the development of what?
The secondary sex characteristics:
- Muscle & Skeletal development
- Deeper voice
- Aggression
- Facial, Axillary & pubic hair growth
- Production & maturation of sperm
Where is testosterone production regulated?
Hypothalamus and anterior pituitary gland - APG, also produces LH, which stimulates testosterone secretion.
Ovaries produce?
Estrogen - Secondary sex characteristics - Breasts, Hair, menstruation, fat deposition. (hypothalamus/APG) Also produces FSH to stimulate estrogen secretion.
Where is the pineal gland?
A small gland attached to the inferior surface of the corpus callosum.
The pineal gland secrets what?
Melatonin - regulating the biological clock, increases during darkness, decreases during light.
Prostaglandins are?
- Localized hormones
- Released by cells in response to chemical or mechanical stimuli
- Activated by extracellular enzymes
- Rapidly inactivated.
What do prostaglandins function in?
- Contraction of the smooth muscles in the uterus, bronchioles, and blood vessels.
