Endocrine System

Question 1

What can hormones control

Answer 1

Rate of enzymatic reactions, transport of ions/molecules across membranes, and gene expression/synthesis of proteins

Question 1

What types of ligands have cytoplasmic/nuclear receptors

Answer 1

Small, non polar, lipophilic, steroid-like ligands

Question 2

What are the features of the endocrine system and hormones

Answer 2

One gland/tissue may secrete multiple hormones, but one cell usually only makes one kind of hormone

Question 3

What is typically the largest endocrine gland in the body

Answer 3

Adipose tissue

Question 4

What are endocrine disruptors

Answer 4

Exogenous mimics (antagonists)

Question 5

What is the half-life of a hormone

Answer 5

How long it takes for the concentration to decrease by 1/2

Question 6

What 2 organs are mainly responsible for inactivating or removing hormones

Answer 6

The kidneys and the liver

Question 7

What is a chaperone protein

Answer 7

A protein that binds to hormones in the blood (that hormone can’t leave) to prevent it from degradingW

Question 8

What are the 3 kinds of hormones

Answer 8

Peptide, steroid, amine (act peptide or steroid-like)

Question 9

How are peptide hormones made

Answer 9

Synthesis similar to other proteins (mRNA, RER, Golgi)
mRNA translates into preprohormone, modified into prohormone, signal peptide sequence removed, folded into hormone

Question 10

What is a preprohormone

Answer 10

A string of amino acids translated by the ribosome

Question 11

Where are peptide hormones kept before release

Answer 11

Secretory vesicles

Question 12

What are the characteristics of peptide hormones

Answer 12

Most common, water soluble (lipophobic/hydrophilic), bind to surface membrane receptors, short 1/2 life (seconds to minutes), rapid effects (must be secreted continually for long-lasting effects), released on demand

Question 13

What are the characteristics of steroid hormones

Answer 13

Cholesterol-derived (lipophilic/hydrophobic), have protein carriers/chaperones, can’t be stored, made on demand (RER and mitochondria) based on rate of release because released immediately, only made in a few organs, longer 1/2 life, cytoplasmic or nuclear receptors (mostly)

Question 14

What determines whether a cell can make a particular hormone

Answer 14

What enzymes it has

Question 15

What type of effects do steroid hormones have

Answer 15

Slower acting, longer lasting, usually genomic/altering gene expression and protein synthesis

Question 16

What are the two amino acids amine hormones come from

Answer 16

Tryptophan (makes melatonin in pineal gland), and tyrosine (makes catecholamines and thyroid hormones)

Question 17

What amine hormone is peptide-like

Answer 17

Catecholamines (epinephrine, norepinephrine, and dopamine)

Question 18

Which amine hormones are steroid-like

Answer 18

Melatonin and thyroid hormones

Question 19

What is 1 difference between steroid hormones and thyroid hormones

Answer 19

Thyroid hormones are made in advance and kept in secretory vesicles

Question 20

What is characteristic of a simple endocrine pathway

Answer 20

Endocrine cell directly senses stimulus, integrates, and responds by secreting its hormones (no neurons)

Question 21

What are 2 examples of a simple endocrine pathway

Answer 21

Parathyroid glands and pancreas (insulin and glucagon)

Question 22

What are the characteristics of a complex endocrine pathway

Answer 22

Hypothalamic-pituitary (HP) axes have 3 integrating centers

Question 23

What are the 3 integrating centers in an HP axis

Answer 23

Hypothalamus (neural), pituitary (master controller of ES), and endocrine gland/target of pituitary hormone)

Question 24

What does the hypothalamus do

Answer 24

Links NS to ES, receives and integrates info about body's homeostasis, and uses that info to control the secretion of pituitary hormones

Question 25

What are the 2 parts of the pituitary gland

Answer 25

Posterior is extension of hypothalamus (neural tissue), and anterior is endocrine gland made of epithelial tissue

Question 26

What does the posterior pituitary gland secrete

Answer 26

Vasopressin and oxytocin (neurohormones)

Question 27

What is a tropic hormone

Answer 27

A hormone that controls the secretion of another hormone

Question 28

What are the 6 tropic hormones secreted by the anterior pituitary

Answer 28

Prolactin, growth hormone, thyroid stimulating hormone (thyrotropin), adrenocorticotropic hormone (corticotropin), and gonadotropins (luteinizing hormone and follicle-stimulating hormone)

Question 29

What are the releasing hormones

Answer 29

Short peptides stores in hypothalamic cells, released into median eminence, TRH, RH (GHRH), Gonadotropin RH (GRH/GnRH), PRF, and CRH

Question 30

What connects the hypothalamus to the anterior pituitary and why

Answer 30

A portal system (2 capillary beds) to avoid dilution

Question 31

How is hormone release regulated

Answer 31

Long-loop feedback (hormone goes to pituitary and hypothalamus), and short-loop feedback (pituitary hormone goes to hypothalamus)

Question 32

Which feedback loop holds more weight in terms of controlling hormone release

Answer 32

Long-loop feedback

Question 33

What are the 2 regions of the adrenal gland

Answer 33

Cortex (true endocrine gland that secretes 3 kinds of hormones), and the medulla (modified sympathetic ganglion/nervous tissue) that secretes catecholamines (mostly epinephrine) due to sympathetic nervous system

Question 34

What 3 major kinds of steroid hormones does the adrenal cortex secrete

Answer 34

Mineralocorticoids, glucocorticoids (slower, longer lasting, e.g cortisol), and sex hormones (a little)

Question 35

What is synergism

Answer 35

When the sum of 2 hormones efforts is more than the simple sum of each hormone on its own

Question 36

What is permissiveness

Answer 36

When 1 hormone (which doesn't have an effect) is necessary to allow the other to have a full affect

Question 37

What is antagonism in hormone interactions

Answer 37

When 2 hormones have opposite effects

Question 38

What is hypersecretion and how is it usually caused

Answer 38

Hormone excess caused by tumors/cancer and autoimmune diseases where antibodies bind and activate receptors in the body

Question 39

What is hypo secretion and how is it caused (endocrine system)

Answer 39

Hormone deficiency caused by decreased synthesis or damage of a gland

Question 40

What are the 3 endocrine pathologies

Answer 40

Hypersecretion, hypo secretion, or abnormal responsiveness of target tissue to hormones (caused by changes in receptors by phosphorylation, etc. or 2nd messenger)

Question 41

What are the classifications of endocrine pathologies

Answer 41

Primary (endocrine gland dysfunction), secondary (pituitary dysfunction), or tertiary (hypothalamus dysfunction)