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30 Cards in this Set
- Front
- Back
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what are the characteristics of the endocrine system?
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1. slower than the nervous system
2. longer lasting responses 3. more generalized 4. regulation |
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what functions does the endocrine system regulate?
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1. metabolism
2. growth and development 3. reproduction 4. behavior |
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what are some components of the endocrine system that are all responsible for secreting hormones?
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1. cells
2. tissues 3. organs |
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hormones are
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1. responsible for chemical messages
2. secreted into body fluids 3. have specific action on target tissues |
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what is a target tissue
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any tissue that has receptor cells for a specific hormone
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what are glands and what are the two types of glands
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body structure that is specialized for secretion
endocrine and exocrine |
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describe exocrine glands and give an example
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*not a part of the endocrine system**
1. secretes substances via ducts that open onto free surfaces 2. duct-tubular passages 3. free surfaces ex:sweat on skin, digestive enzymes |
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describe endocrine glands and give an example
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*are part of the endocrine system**
1. ductless glands and tissue that release hormones 2. work very closely with the nervous system ---together they regulate the bodies metabolic activities ---maintain homeostasis |
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name the 4 types of endocrine signaling
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1. classical-hormone secreted by cells and transported by blood
2. neroendocrine-neurohormones secreted by neuroendocrine cells and transported by blood/interstitial fluid 3. paracrine - hormone secreted by cell and acts on nearby cells 4. autocrine- hormones that act on the cell that produces it |
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what types of signaling do local regulators use?
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paracrine and autocrine
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what are the four hormone chemical groups and describe them
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1. fatty acid derivatives-contain long hydrocarbon chains 2. steroid hormones-lipids(cholesterol)
3. amino acid derivatives-simple(adrenaline/epinephrine) 4. peptide and protein hormones (short peptides) |
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what are some examples of fatty acid hormones?
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1. Juvenile hormones in insects
-preserves their juvenile structure during molting 2. prostiglandis- produced by cells of many mammals -local regulator -paracrine signaling |
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what does prostiglandis regulate?
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1. blood pressure
2. smooth muscle contraction 3. inflammation |
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what are some examples of steroid hormones?
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1. molting hormone in insects
2. cortisol-hydrocortosone- stress hormone 3. estradial- form of estrogen |
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what are some examples of peptide
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1. oxytocin-stimulate uterine contraction and milk production
2. antidiretic hormone (ADH)-H2O absorption in the kidneys |
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what are some protein hormones?
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insulin- 2 peptide chains joined by disulfide bond
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describe negative feedback
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1. glands receive information about amount of hormone or some other substance
2. glands respond to restore homeostasis 3. if there is more= lower production if less=increase production 4. effect is opposite to stimulus |
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what is the job of Parathyroid hormone in relation to calcium
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PTH stimulate the release of calcium from the bones
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describe receptors and what they are designed to do
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1. they are large proteins or glycoproteins on resurface of target cells
2. they recognize and bind to specific hormones -very specific-one type will only bind to specific type |
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describe receptor down regulation
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when the hormone levels in the cell are too high, down regulation will create less receptors so it doesn't get any more hormones into the cell
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describe receptor up regulation
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if the level of hormone inside the cell are too low, up regulation will create more receptors to collect more hormones from outside the cell and send it into the cell
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describe the process of regulation of gene expression
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1. steroid and thyroid hormones (small and lipid sol.) easily pass through membrane
2. enter target cell and either a. binds to a receptor on the cytoplasm (forms hormone receptor complex) which to nucleus or b. passes into nucleus then creates hormone receptor complex. 3. binds to a specific site of DNA 4. changes conformation of DNA and leads to mRNA transcription or repression -protein synthesis or repression |
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describe the process of signal transduction
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1. hormones bind to receptors on cell membrane
-g Protein linked receptor -enzyme linked receptor 2. secondary messenger is used |
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describe an example of signal transduction
-G-protein linked receptor |
1. hormone binds to a particular receptor (not G-prot) outside of the cell
2. hormone receptor complex binds to g-protein 3. stimulates it to release GDP and GTP 4. bind causes conformation change in g-protien 5. g-protein binds to adenylyl cyclase (enzyme) 6. catalizes the conversion of ATP to cAMP 7. cAMP activates protein kinace 8. protein kinase adds phosphate group to protein 9. post-translational control |
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what do neurohormones stimulate?
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1. growth and development
2. reproduction 3. metabolism 4. behavior |
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how do neurohormones work in insects?
example |
temperature activates neuroendocrine cells to produce brain hormone which stimulates the glands in the thorax to produce molting hormone
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what are the functions of a molting hormone in insects?
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1.stimulates growth and molting
2. stimulate metamorphosis |
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describe the relationship between JH and MH
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1. when JH levels are high, MH is only in charge of increasing the size of the insect
2. Jh will keep decreasing at each molt until MH levels become higher the the organism will go through metamorphosis |
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what is the use of synthetic JH
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insecticides to prevent insects from molting and becoming adults who reproduce
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describe hypo and hyper secretion
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hypo-decreased output- target cells under stimulated
hyper- increased output-target cells overstimulated |
