bio 105: the endocrine system - napa valley college endocrine... · bio 105: the endocrine system...

4/7/2016

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Bio 105: The Endocrine System

Lecture 12

Chapter 10

Copyright © 2009 Pearson Education, Inc 1

Outline

• Function of the Endocrine System

• Hormones and Neurotransmitters

• Types of Hormones & Their actions

• Endocrine glands/organs and Hormones


Review Questions

• Muscles cells are bundled together, these bundles are called _______.

• What is the plasma membrane called in muscle cells?

• What is the oxygen binding protein similar to hemoglobin, but found only in muscles?

• Where is Ca++ stored in muscle cells? • What does Ca++ bind to when it is

released?


Homeostasis

• Nervous and Endocrine Systems

– Exert control over the other systems

–Maintain homeostasis

–Work closely to govern the internal organs


Endocrine System

• Function

–Work with the nervous system to regulate and control the other systems and maintain homeostasis

– Functions by releasing hormones which travel through the body to target cells


Review Questions

• Glands are secretory cells or structures derived from what type of tissue? a) Muscle

b) Connective

c) Epithelial

d) Nervous

• What type of glands do not have tubes or ducts, but secrete hormones directly into the blood stream?


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Endocrine System Communication

Figure 10.1


Hormones

• Chemical messengers

• Secreted by one cell and travels to another

• Affects only the target cells with the correct receptor



Hormones VS Neurotransmitters

• Endocrine VS Nervous Systems

–Both controlled by negative feedback

–Work together to maintain homeostasis


Hormones VS Neurotransmitters

Differences Hormones Neurotransmitte

rs

Where is it located?

Distributed throughout the body in blood

stream

Localizsed to nerve synapse

How long does it take to act?

Slow to act Quick acting

How long does it last?

Remains longer in the body

Taken away quickly


Hormones

• 2 types

–Water soluble

– Lipid soluble

• Amino acid hormones

– Single amino acid – ex. Epinephrine

–Polypeptides – ex. Human growth hormone

–Water soluble


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Amino Acid

Figure 2.22


Review Questions

• Are amino acids hydrophilic or hydrophobic?

• Can amino acids freely cross the plasma membrane?


Water Soluble Hormones

• Bind to a receptor on surface of the target cells (ex. muscle cells)

• Bind of the hormone epinephrine to the receptor triggers the formation of a secondary messenger (ex. cAMP)

• Secondary messenger triggers cascade of events ending in celluar activity


Water Soluble Hormones -

cAMP Mediation

Figure 10.4


Lipid Soluble Hormones

• Steroid Hormones

– Structure similar to cholesterol

– Examples

• Estrogen

• Testosterone


Review Questions

• What biological molecule are steroids?

• Are steroids hydrophilic or hydrophobic?

• Can steroids freely cross the plasma membrane?

• What do you call the process of when DNA is copied to make mRNA?

• What is the product of translation?


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Lipid Soluble Hormones - Steroids

• Enter the target cells – Can freely pass through the plasma membrane

• Binds with a receptor (inside the cell)

• The hormone-receptor complex binds to DNA in the nucleus and activates the transcription of DNA to make mRNA

• mRNA leaves the nucleus, binds to a ribosome and is translated to make proteins


Lipid-soluble Hormones

Figure 10.3

Steroid hormone

Receptor

Nuclear pore

Plasma membrane of target cell (lipid bilayer)

Nuclear envelope

Cytoplasm

Extracellular fluid

Nucleus Step 4: The hormone- receptor complex binds to DNA.

Step 1: The steroid hormone diffuses through the plasma membrane of the target cell.

Step 2: The steroid hormone binds to a receptor in the cytoplasm.

Step 3: The hormone- receptor complex enters the nucleus.

Step 7: Enzymes alter the activity of the cell.

Step 5: Certain genes are activated.

Step 6: Proteins, including enzymes, are synthesized.


Water Soluble VS Lipid Soluble

• Water Soluble – Take less time to act

–Do not enter target cell • Work via secondary messengers

• Lipid Soluble – Take longer to act

• Cause transcription and translation to make a protein

– Enter the cell Copyright © 2009 Pearson Education, Inc 21

Hormones

• Water soluble Hormones

–Cyclic AMP pathway

–https://www.youtube.com/watch?v=Y2er_Dfgg44

• Lipid Soluble Hormones

–https://www.youtube.com/watch?v=C4m3ZT4Byvo


Endocrine Glands and Organs

• Primary – Pituitary – Thyroid – Parathyroid – Adrenals – Pineal – Hypothalamus – Thymus

• Secondary – Pancreas – Ovaries – Testes – Heart – Placenta – Stomach – Intestines – Kidneys


Endocrine System

Figure 10.2 (1 of 2)

Parathyroid glands (two of four)

Pineal gland

Thymus gland

Kidney

Adrenal gland (one on each kidney) Adrenal cortex

Adrenal medulla

Heart


https://www.youtube.com/watch?v=Y2er_Dfgg44

https://www.youtube.com/watch?v=Y2er_Dfgg44

https://www.youtube.com/watch?v=C4m3ZT4Byvo

https://www.youtube.com/watch?v=C4m3ZT4Byvo

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Endocrine System

Figure 10.2 (2 of 2)

Uterus

Thyroid gland

Pancreas

Testis (one of a pair)

Ovary (one of a pair)

Small intestine

Stomach

Copyright © 2009 Pearson Education, Inc 25 Copyright © 2009 Pearson Education, Inc 26


Hypothalamus

• Regulates the internal environment through the autonomic nervous system

–Heartbeat

–Body temperature

–Water balance


Hypothalamus

• Controls

–Glandular secretions of the pituitary gland

• Produces

–Antidiuretic hormone (ADH)

–Oxytocin

–Hypothalamic-releasing hormones

–Hypothalamic-inhibiting hormones


Diuresis

• A diuretic will make your urine

–Dilute?

–Concentrated?

• An antidiuretic will make your urine

–Dilute?

–Concentrated?


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Hypothalamus

• Controls

–Glandular secretions of the pituitary gland

• Produces

–Antidiuretic hormone (ADH)

–Oxytocin

–Hypothalamic-releasing hormones

–Hypothalamic-inhibiting hormones


Hypothalamus – ADH & Oxytocin

• Produced by

–Neurosecretory cells in the hypothalamus

• Stored in the posterior lobe of the pituitary

• Posterior lobe releases these hormones when needed


ADH – Antidiuretic Hormone

• Function

–Regulates water absorption in the kidneys

• Target

–Kidneys


Antidiuretic Hormone

(ADH)

Image From: https://www.studyblue.com/notes/note/n/lecture-exam-endocrine-system/deck/6009368


ADH Disorders

• Disease

–Diabetes Insipidus

• Cause

–Deficiency of ADH

– Excessive urine production dehydration

• Treatment

–Administer synthetic ADH


Oxytocin (OT)

• Function

– Stimulates uterine contraction during childbirth and milk letdown

• Target

–Uterus

–Mammary glands

• Synthetic: Pitocin


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Hypothalamus

• Hypothalamic-releasing hormone

• Hypothalamic-inhibiting hormone

–Both produced by hypothalamus

• Target

–Anterior Pituitary Gland

–Releasing release/secretion of hormones

– Inhibiting inhibits release/secretion


Hawaii

Image From: http://www.qantas.com/au/en/destinations/north-america/usa/hawaii.html Copyright © 2009 Pearson Education, Inc 38

Anterior Pituitary Gland

• Produces

– Thyroid stimulating hormone (TSH)

–Adrenocorticotropic hormone (ACTH)

–Gonadotropic hormones (FSH and LH)

–Prolactin (PRL)

–Growth Hormone (GH)


Anterior Pituitary Gland • Thyroid stimulating hormone (TSH)

– Thyroid – Produce T3 and T4

• Adrenocorticotropic hormone (ACTH) – Adrenal cortex – Produce glucocorticoids

• Gonadotropic hormones (FSH and LH) – Ovaries and Testes – Produce estrogen and testosterone

• Prolactin (PRL) – Breast – Milk let-down

• Growth Hormone (GH) – Bones and muscle – Growth


Pituitary Gland – Anterior and Posterior

Figure 10.6

Posterior pituitary

Oxytocin (OT)

Antidiuretic hormone (ADH)

Kidney tubules

Smooth muscle in uterus

Anterior pituitary

Thyroid- stimulating hormone (TSH)

Thyroid gland

Adrenocortico- tropic hormone (ACTH)

Cortex of adrenal gland

Prolactin (PRL)

Mammary glands

Growth hormone (GH)

Bones, muscles

Follicle-stimulating hormone (FSH) and Luteinizing hormone (LH)

Ovaries, testes

Hypothalamus

ADH and OT travel to the ends of the cells in the posterior pituitary, where they are released into the bloodstream to influence target tissues.

Nerve cells in the hypothalamus produce antidiuretic hormone (ADH) and oxytocin (OT).

Mammary glands

Releasing and inhibiting hormones travel by way of the bloodstream to the anterior pituitary and cause it to modify secretion of its six hormones (FSH, LH, GH, PRL, ACTH, and TSH).

Nerve cells in the hypothalamus secrete releasing hormones and inhibiting hormones.


Posterior Pituitary Gland

• 2 sections to pituitary gland

–Anterior

–Posterior

• Posterior Pituitary Gland

–Receives ADH and Oxytocin from hypothalamus

– Stores and Releases


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Anterior Pituitary Gland

• Produces hormones

• Releases when receives hypothalamic-releasing hormones from the hypothalamus


Thyroid Stimulating Hormone (TSH)

• Produced by

–Anterior Pituitary

• Function

– Stimulates thyroid gland to produce thyroxine

• Target

– Thyroid gland


Adrenocorticotropic Hormone (ACTH)

• Produced by

–Anterior Pituitary

• Function

– Stimulates adrenal cortex to produce cortisol

• Target

–Adrenal cortex


Gonadotropic Hormones

• Produced by – Anterior Pituitary

• Function – Stimulate gonads to produce gamets and

hormones – FSH – LH

• Target – Ovaries – Testes


Gonadotropic Hormones

• Follicle Stimulating Hormone (FSH) – Stimulates gamete development

–Males and Females

• Luteinizing Hormone (LH) – Stimulates ovaries to produce estrogen and

progesterone in females

– Stimulates testes to produce testosterone in males


Prolactin (PRL)

• Produced by

–Anterior Pituitary Gland

• Function

–Causes mammary glands to develop and produce milk

• Target

–Mammary Glands


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Growth Hormone

• Produced by –Anterior Pituitary Gland

• Function –Promotes skeletal and muscular growth

• Target –Bones

–Muscles

–Cartilage


Growth Hormone Disorders

• Disease

–Gigantism

• Cause

– Too much GH during childhood

• Treatment

– If caused by pituitary tumor – remove or reduce the tumor


Gigantism

Figure 10.7



• Disease –Acromegaly

• Cause – Too much GH in adulthood

– Thickening of the bones of the extremities, face and tongue

• Treatment – Same as gigantism


Acromegaly



• Disease

–Pituitary Dwarfism

• Cause

– Insufficient GH production

– Sterility

• Treatment

–Administer GH during childhood


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Pituitary dwarfism

Figure 10.9


Review Questions

• What hormone stimulates water resorption by the kidneys?

• What hormone stimulates the adrenal cortex to produce cortisol?

• Which gland produces oxytocin?

• Which gland produces prolactin?


Hypothalamus & Pituitary Gland

• https://www.youtube.com/watch?v=TVhm2rBGhB0

• ADH = Vasopressin


Bahamas

Image From: https://www.ncl.com/cruise-destinations/bahamas-florida-cruises


Bahamas

Image From: http://wikitravel.org/en/Bahamas


Thyroid Gland Hormones

Figure 10.11a

Opening to trachea

Larynx

Thyroid gland

Parathyroid glands

Trachea

Front view Back view

(a) The thyroid gland lies over the trachea, just below the larynx. Copyright © 2009 Pearson Education, Inc 60

https://www.youtube.com/watch?v=TVhm2rBGhB0




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Thyroid Gland

• Large gland located below the larynx

• Requires iodine to make hormones

• Produces

– Thyroid hormones (TH)

• Thyroxine (T4)

• Triiodothyronine (T3)

–Calcitonin


Thyroid Gland

• Thyroid Hormones –Regulates metabolism

– Stimulates protein synthesis

– Stimulates breakdown of lipids

– Stimulates use of glucose for the production of ATP

• Target –Most cells in the body


Thyroid Gland Disorders

• Disease

– Simple Goiter

• Cause

–A diet deficient in iodine

• Treatment

– Iodine supplements or administration of thyroid hormone



• Disease – Cretinism

• Cause – Too little TH during fetal development or

infancy

– Dwarfism and delayed mental and sexual development

• Treatment – Administer TH



• Disease – Myxedema

• Cause – Too little TH in adulthood – Fluid accumulates in facial tissues – Decrease in alertness, body temperature and

heart rate

• Treatment – Administer TH



• Disease

–Graves’ disease

• Cause

–Oversecretion of TH

–An autoimmune disorder due to production of antibodies that mimic the action of TSH


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• Graves’ Disease cont’d

• Symptoms – Increased metabolic rate and heart rate

– Sweating, nervousness and weight loss

– Many have exophthalmos

• Treatment – Drug that blocks the synthesis of TH

– Reduce thyroid gland by surgery or radioactive iodine


Exopthalmos

Figure 10.12c


Review Questions

• What is the target of thyroxine?

• Does calcitonin lower or raise the blood’s calcium level?

• What gland produces calcitonin?


Image From: http://www.hawaiilife.com/articles/2012/03/good-news-vacation-rental-owners/


bio 105: the endocrine system - napa valley college endocrine... · bio 105: the endocrine system...

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