Term
| Where does the word Hormone come from? |
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Definition
From the Greek word Hormaein- "To Excite" |
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Term
| Name some major endocrine glands Dr. Romito mentioned |
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Definition
Major ones are Pancreas, thyroid glands, hypothalamus, the pituitary, and the reproductive organs. Remember HPA (hypthalamus-pituitary-Adrenal) Axis for Cortisol (Just in case she also said heart, kidneys, the CNS, the small intestine, and stomach) |
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Term
Describe Endocrine signaling action (How the hormones reach the tagets) |
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Definition
| Endocrine glands release their hormones into the general circulation which travel to distant site and effect specific target cells |
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Term
Describe what a neurosecretory cell is and how it works. Provide an example |
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Definition
neuroendocrine or neurosecretory cells convert the electrical signal of neuron to a chemical or hormone signal in the blood Adrenal Medulla converts the sympathetic signal into epinephrine. |
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Term
Explain the three types of feedback systems |
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Definition
Closed Negative Feedback Gland A produces hormone A which stimulates gland B to produce hormone B. Hormone B then turns off gland A. Example is Open Negative Feedback External Stimulation (baby suckling) causes gland A (posterior pituitary) to produce hormone A (oxytocin) which stimulates gland B to substance (Milk). External stimulation stops, process stops. Positive Feedback In child birth, oxytocin causes uterine contractions, the uterine contractions cause release of more oxytocin, which cause more uterine contractions--until baby pops out. Self Perpetuating Cycle |
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Term
| Give an example of a feed forward system |
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Definition
| The preemptive secretion of insulin from the pancreas in anticipation of stealing pizza from the Delt's meeting. |
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Term
| Even at low concentrations, how can hormones have such a large scale effect? |
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Definition
Signal Amplification i.e. You tell two friends, they each tell two friends, etc. |
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Term
| What are pleiotropic effects? |
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Definition
| A hormone has many different effects on the same tissue. |
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Term
| Describe Multiplicity of Regulation |
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Definition
| Many different hormones effecting same organ. i.e. Liver is effected by glucagon and insulin. |
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Term
| Name three different types of hormone secretion patterns. |
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Definition
1. Pulsatile (Most Common) 2. Circadian 3. Episodic |
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Term
| Romito quesiton: What type of feed back system is characterized by consequences of hormone secretion result in secretory cells intensifying their secretion of that hormone? |
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Definition
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Term
| Name the 3 major classes of Hormones |
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Definition
1. Amino Acid Derivatives 2. Polypeptides 3. Steroids (fatty acid derivatives--Hormone like activity) |
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Term
| Name the amino acid that makes up Thyroid hormones (T3, T4) and Catecholamines (Epi, NE) |
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Definition
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Term
Even though Catecholamines and thyroid hormones come from the same a.a. derivative...how is their solubility in circulation different. Name the A.A. derivative |
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Definition
Thryroid hormones must be bound to a carrier protein (TBG) in the circulation while Catecholamines are frequently found free. Thryroid hormones are lipid soluable and can cross membranes to the intracellular receptors while catecholamines are non lipid soluable and have receptors on cell surface. Tyrosine, OBVIOUSLY (Thanks Romito) |
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Term
What are some basic characteristics of polypeptide hormones and list a few examples. |
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Definition
Synthesized by ribosomes and packaged by golgi Hydrophilic, don't need carrier proteins to circulate in blood. Examples: Insulin, TRH, ACTH, GH |
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Term
| What is the precursor for steroid hormones? |
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Definition
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Term
| What are the major sites of synthesis for steroid hormones? |
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Definition
1. Adrenal Glands 2. Reproductive glands 3. Liver and kidney |
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Term
| How many rings do steroid hormones have? |
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Definition
4 (Four) Vitamin D has 3 rings and still has steroid-like activities. |
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Term
| Describe the solubility characteristics of steroid hormones |
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Definition
Lipid soluable (can cross membranes) Need carrier proteins in the blood stream. |
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Term
| In the formation of steroids, what is cholesterol converted to, before becoming the 5 classes of steroid hormones? |
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Definition
Pregnenolone memory tactic: Cholesterol was pregnant and alone before having 5 steroidal kids |
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Term
| Name the five classes of steroid hormones |
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Definition
Mineralcorticoids Glucocorticoids Androgens Estrogens Progestins For the first major three (Salty, Sweet, and Sexy) ...Just like Romito |
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Term
| What is the precursor for Eicosinoids and what are four examples? |
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Definition
Arachidonic Acid Prostaglandins, prostacyclins, leukotrienes, and thromboxanes. |
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Term
| What are two general carrier proteins? |
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Definition
Albumin and transthyretin TBG (thryroxine binding globulin) is probably good to know for T3 and T4 |
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Term
| Describe the steps in the cyclic AMP System |
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Definition
1. hormone binds 2. activation adenylyl cyclase in the membrane 3. Converts ATP to cAMP. 4. cAMP activates protein kinase A 5. Protein kinase A can interact with a number of proteins 6. Biological Effect (BOLD is Romito Question) |
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Term
| When a hormone binds to a receptor, Ca floods from where (inside or outside) to here (inside or outside) |
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Definition
Calcium floods from the outside of the cell to the inside. Calcium wants to go to PARTY? |
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Term
| Briefly describe the IP3-DAG System |
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Definition
1. phosphatidylinisitol is converted to PIP2 by the addition of a few phosphate molecules and catalyzed by phospholipase C (PIP2 is the immediate precursor to DAG and ip3) 2. IP3 leaves the cell membrane and participates in interaction with Calcium—which is stored in the ER. 3. The IP3-Ca and DAG-Phospholipase C complexes regulate enzymes which create biological effects. |
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Term
| In general, what hormones have the shortest lifespans and which have the longest? |
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Definition
Short: Eicosinoids and Catecholamines Long: Thyroid Hormones and Steroids |
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Term
| Are carrier bound hormones physiologically active? |
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Definition
| No, only the free hormones are |
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Term
| What are the major degradation pathways for hormones? |
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Definition
Liver (Steroid Hormones) Kidneys (Catecolamines) Receptor Mediated endocytosis (Peptide Hormones) |
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Term
True or False The rate of steroid hormone synthesis determines the rate of hormone secretion because steroid hormones are secreted on demand. |
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Definition
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