Unit 6 Endocrine System Review Guide

Review for Endocrine Exam

1. Hormone – definition

2.  2 Types of Glands – Endocrine and Exocrine

3.  Second Messenger, Target Organ, Hypersecretion, Hyposecretion, receptor

4.  2 Types of Hormones – Protein, Steroid

5.  2 Types of Feedback – Positive and Negative

6.  Difference between normal endocrine glands and Prostaglandins (PGs)

Review -- Hypothalamus

Where Located?  Brain

Hormones it makes:

Makes ADH and Oxytocin à  dumped into the posterior pituitary by neurons

ADH à  water retention by kidneys

Oxytocin à  causes labor contractions (positive feedback)

Releases Inhibitor and Releasing hormones to turn on or shut off the Anterior Pituitary

Review – Anterior Pituitary

Releases 4 Tropic Hormones – hormones that activate other glands

TSH – activates thyroid gland

ACTH – activates the Adrenal Cortex

FSH – female à  development of follicle, secretion of estrogen, male à  sperm production

LH – female à  maturation of ovarian follicles, ovulation, development of corpus luteum, male à  secretes testosterone (by testes)

 - MSH -- stimulates the production of melanin (skin pigment)

- GH -- stimulates the growth of muscles, bones, tissues and organs in the body

- Prolactin -- stimulates the production and release of milk by the mammary glands in pregnant women)

Review – Posterior Pituitary

Hormones it releases:

Makes ADH and Oxytocin à  dumped into the posterior pituitary by neurons

ADH à  water retention by kidneys

Oxytocin à  causes labor contractions (positive feedback) 

Review – Pineal Gland

Located – Brain

Hormone released

– Melatonin à onset of puberty and menstrual cycle

Pineal gland is thought to be the internal clock of each individual 

Review -- Thyroid

Located – Neck region below larynx

Hormones Released

Thyroxin (T4), Iodothyronine (T3) à  metabolic hormones (release energy from food)

Calcitonin – decrease calcium in blood by bone resorption

Review – Parathyroid

Where located – On thyroids

How many of them – 4

Hormone released

– PH (parathyroid Hormone)

Increase calcium concentration in blood.  Osteoclasts break down bone tissue and release calcium back into bloodstream 

Review -- Thymus

Where located à  Mediastinum (heart cavity)

Hormone released – Thymosin à  development of the immune system 

The thymus gland is mostly made up of lymphocytes (WBC’s)

Only active in children

Review – Adrenal Cortex

Where located –top of kidneys – outer part

Hormones released

Mineralcorticoids (Aldosterone) àcontrol the amount of sodium (increases) and potassium (decreases)salts in blood

Glucocoticoids à  Cortisol and hydrocortisone à  maintains glucose and blood pressure levels, anti-inflammatory

Secrete sex hormones – Estrogen and testosterone --> stimulates sex drive

Review – Adrenal Medulla

Where located – On top of Kidneys, inner portion

Hormones Released – Epinephrine (adrenaline) and Norepinephrine

Increase heart rate

Increase blood pressure

Increase blood to muscles

Secretes more glucose for energy

Fight or Flight response 

Pancreas – Review

Where Located?  Upper Abdominal Cavity

Endocrine and Exocrine Gland

Islets of Langerhans – release digestive juices into the pancreatic duct (Exocrine)

Hormones Release (Endocrine)

Insulin – decrease blood glucose by cell uptake

Glucagon – increase blood glucose levels

2 types of Diabetes à  mellitus and insipidus

Review -- Ovaries

Where located – Pelvic Cavity

Hormones Released

1.  Ovarian Follicles release Estrogen

2.  Corpus Luteum releases Estrogen and Progesterone

Function

1.  Maintains the menstrual cycle (maintains uterine wall lining)

Review -- Testes

Where located – Pelvic Cavity

Hormone Released – testosterone that is made by the testes

Function – male sex hormone that gives males their characteristics and helps with the production of sperm 

Review – Placenta

Temporary Endocrine gland in pregnant females.

Where located?  Uterus of pregnant females

Hormone(s) released – Chorionic Gonadotropins (GnRH or hCG) that are released by the chorion (outer membrane of the placenta, Estrogen and Progesterone

Function – to maintain the uterine wall from breaking down and stopping the menstrual cycle until the baby is born.

Hormones are taken up by the kidneys and released in urine

– Pregnancy tests are positive if these hormones are present in the urine of pregnant women