endocrine system hormones (ch. 45)
DESCRIPTION
Endocrine System Hormones (Ch. 45). Regulation. Why are hormones needed? chemical messages from one body part to another communication needed to coordinate whole body daily homeostasis & regulation of large scale changes solute levels in blood glucose, Ca ++ , salts, etc. metabolism - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/1.jpg)
Endocrine SystemHormones(Ch. 45)
![Page 2: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/2.jpg)
• Why are hormones needed?– chemical messages from one body part
to another– communication needed to coordinate
whole body– daily homeostasis & regulation of large
scale changes• solute levels in blood
– glucose, Ca++, salts, etc.• metabolism• growth• development• maturation• reproduction
Regulation
growth hormones
![Page 3: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/3.jpg)
Regulation & Communication• Animals rely on 2 systems for regulation
– endocrine system • system of ductless glands
– secrete chemical signals directly into blood– chemical travels to target tissue– target cells have receptor proteins– slow, long-lasting response
– nervous system• system of neurons
– transmits “electrical” signal & release neurotransmitters to target tissue
– fast, short-lasting response
![Page 4: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/4.jpg)
Regulation by chemical messengers
axon
endocrine gland
receptor proteins
target cell
• Neurotransmitters released by neurons• Hormones release by endocrine glands
receptor proteins
hormone carried by blood
neurotransmitter
Lock & Keysystem
![Page 5: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/5.jpg)
Classes of Hormones• Protein-based hormones
– polypeptides• small proteins: insulin, ADH
– glycoproteins• large proteins + carbohydrate: FSH, LH
– amines• modified amino acids: epinephrine, melatonin
• Lipid-based hormones– steroids
• modified cholesterol: sex hormones, aldosterone
insulin
![Page 6: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/6.jpg)
How do hormones act on target cells• Lipid-based hormones
– hydrophobic & lipid-soluble• diffuse across cell membrane & enter cells• bind to receptor proteins in cytoplasm & nucleus• bind to DNA as transcription factors
– turn on genes• Protein-based hormones
– hydrophilic & not lipid soluble• can’t diffuse across cell membrane• bind to receptor proteins in cell membrane• trigger secondary messenger pathway• activate internal cellular response
– enzyme action, uptake or secretion of molecules…
![Page 7: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/7.jpg)
nucleus
target cell
DNA mRN
A protein
blood
proteincarrier
S
S
S
S
Action of lipid (steroid) hormones
binds to receptor protein
cytoplasm
becomes transcription factor
ex: secreted protein = growth factor (hair, bone, muscle, gametes)
2
4
6
cross cell membrane1
steroid hormone
mRNA read by ribosome
5
plasma membrane
protein secreted
7
3
![Page 8: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/8.jpg)
Action of protein hormones
activatesenzyme
activatesenzyme
activates enzyme
ATP
produces an action
P1
2
3
cytoplasm
receptor protein
response
signal
secondarymessengersystem
signal-transduction pathway
acts as 2° messenger
target cell
plasma membrane
binds to receptor protein
proteinhormone
ATPactivatescytoplasmicsignal
cAMP
GTP
activatesG-protein
transduction
![Page 9: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/9.jpg)
adrenal gland
Ex: Action of epinephrine (adrenaline)
activatesprotein kinase-A
activatesglycogen phosphorylase
activates adenylyl cyclase
epinephrine
liver cell
releasedto blood
1
2 5
receptorproteinin cell membrane
cytoplasm
6glycogen
activatesphosphorylase kinase
GTP
cAMP4
activatesG protein
ATP
glucose
activates GTP
3
signal
transduction
response7
GDP
![Page 10: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/10.jpg)
Benefits of a 2° messenger system
Amplification!
signal
receptor proteinActivated adenylyl cyclase
amplification
amplification
amplification
amplification
GTP G protein
product
enzyme
protein kinase
cAMP
Not yetactivated
1
2
4
35
6
7
FAST response!
amplification
Cascade multiplier!
![Page 11: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/11.jpg)
Maintaining homeostasis
high
low
hormone 1
lowersbody condition
hormone 2
gland
specific body condition
raisesbody condition gland
Negative FeedbackModel
![Page 12: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/12.jpg)
Controlling Body Temperature
high
low
nerve signals
sweat
nerve signals
body temperature(37°C)
shiver
dilates surfaceblood vessels
constricts surfaceblood vessels
Nervous System Control Feedback
hypothalamus
hypothalamus
![Page 13: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/13.jpg)
liver
pancreas
liver
Regulation of Blood Sugar
blood sugar level(90mg/100ml)
insulin
body cells takeup sugar
from blood
liver storesglycogen
reducesappetite
glucagon
pancreas
liver releasesglucose
triggershunger
high
low
FeedbackEndocrine System Control
islets of Langerhans beta islet cells
islets of Langerhansalpha islet cells
![Page 14: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/14.jpg)
osmoreceptors inhypothalamus
nephron
nephron
Blood Osmolarity
blood osmolarityblood pressure
ADH
increasedwater
reabsorption
increasethirst
renin
increasedwater & saltreabsorption
high
FeedbackEndocrine System Control
pituitary
angiotensinogenangiotensin
adrenalgland
aldosterone
JuxtaGlomerularApparatus
nephron(JGA)
low
![Page 15: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/15.jpg)
Nervous & Endocrine systems linked• Hypothalamus = “master nerve control center”
– nervous system– receives information from nerves around body about
internal conditions – releasing hormones: regulates release of hormones from
pituitary• Pituitary gland = “master gland”
– endocrine system– secretes broad range
of “tropic” hormones regulating other glands in body
hypothalamus
pituitary
posterior
anterior
![Page 16: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/16.jpg)
Thyroid gland
hypothalamus
anteriorpituitary
gonadotropic hormones:follicle-stimulatinghormone (FSH) & luteinizing hormone (LH)
Mammaryglandsin mammals
Musclesof uterus
Kidneytubules
posteriorpituitary
thyroid-stimulating hormone(TSH)
antidiuretic hormone(ADH)
Adrenalcortex
Boneand muscle
Testes Ovaries
Melanocytein amphibian
adrenocorticotropic
hormone (ACTH)melanocyte-stimulating hormone(MSH)
oxytocin
prolactin (PRL)
grow
th h
orm
one (
GH)
tropic hormones = target endocrine glands
![Page 17: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/17.jpg)
Homology in hormones
prolactin
mammals
milkproduction
birds
fatmetabolism
amphibians
metamorphosis& maturation
fish
salt &water
balance
growth& development
What does this tell you about these hormones?
growthhormone
same gene familygene duplication?
How could these hormones have different effects?
![Page 18: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/18.jpg)
Regulating metabolism • Hypothalamus
– TRH = TSH-releasing hormone• Anterior Pituitary
– TSH = thyroid stimulating hormone• Thyroid
– produces thyroxine hormones– metabolism & development
• bone growth• mental development• metabolic use of energy• blood pressure & heart rate• muscle tone• digestion• reproduction
tyrosine+
iodine thyroxines
![Page 19: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/19.jpg)
GoiterIodine deficiency causes thyroid to enlarge as it tries to produce thyroxine
thyroxines
tyrosine+
iodine✗✗
+
![Page 20: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/20.jpg)
Regulation of Blood Calcium
blood calcium level(10 mg/100mL)
calcitonin
parathyroid hormone (PTH)
Ca++ uptakein intestines
high
low
FeedbackEndocrine System Control
kidney reabsorption
of Ca++bones
release Ca++
kidney reabsorption
of Ca++Ca++ deposited
in bones
activated Vitamin D
thyroid
parathyroid
![Page 21: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/21.jpg)
corpusluteumovary
Female reproductive cycle
pregnancy
maintainsuterus lining
no
yes
Feedback
estrogenegg
matures &is released(ovulation)
builds up uterus lining
FSH & LHprogesterone
progesterone
fertilized egg(zygote)
hCG
corpus luteum breaks downprogesterone drops
menstruation
corpusluteum
maintainsuterus lining
GnRH
pituitarygland
hypothalamus
![Page 22: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/22.jpg)
![Page 23: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/23.jpg)
Effects of stress on a body
Spinal cord(cross section)
Nervesignals
Nervecell
Releasinghormone
Stress
Hypothalamus
Anterior pituitary
Blood vessel
ACTH
Adrenalgland
Kidney
adrenal medullasecretes epinephrine
& norepinephrineAdrenal cortexsecretesmineralocorticoids& glucocorticoids
(B) LONG-TERM STRESS RESPONSE(A) SHORT-TERM STRESS RESPONSE
Nerve cell
Effects of epinephrine and norepinephrine:
1. Glycogen broken down to glucose; increased blood glucose
2. Increased blood pressure3. Increased breathing rate4. Increased metabolic rate5. Change in blood flow patterns, leading
to increased alertness & decreased digestive & kidney activity
Effects of mineralocorticoids:
1. Retention of sodium ions & water by kidneys
2. Increased blood volume & blood pressure
Effects of glucocorticoids:
1. Proteins & fats broken down & converted to glucose, leading to increased blood glucose
2. Immune system suppressed
MEDULLA CORTEX
![Page 24: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/24.jpg)
2009-2010
Any Questions??
Robert Wadlow1918-1940
8' 11"
![Page 25: Endocrine System Hormones (Ch. 45)](https://reader035.vdocuments.site/reader035/viewer/2022062218/5681649e550346895dd68679/html5/thumbnails/25.jpg)
Make sure you can do the following:1. Compare and contrast the regulatory structures and
functions of the nervous and endocrine systems2. Diagram the processes by which signal transduction
occurs in multicellular animals, including steroid and lipid hormone signaling pathways
3. Diagram the endocrine feedback loops that contribute to regulation of multicellular animals including pituitary, thyroid, pancreatic, and gonadal hormones.
4. Explain the causes of enodcrine system disruptions and how disruptions of the endocrine system can lead to disruptions of homeostasis.