Transcript Unit 2 Power Point 2.3 and 2.4

 Neurons
use impulses to relay
messages from throughout the
body
 What other means do humans
have to provide
communication within in the
body

The glands that secrete hormones are
either
 endocrine

glands
exocrine glands
.

When imbalances in hormone levels
occur, diseases or dysfunctions can result.
excretes
its essential
product by way of a Duct
to some environment
external to itself, either
inside the body or on a
surface of the body.
 Sweat
glands
 Salivary glands
 Mammary glands
 Pancreas
 Liver
 Endocrine
glands release more than 20
major hormones directly into the
bloodstream without the use of ducts
 or by diffusion into surrounding tissue where
it affects the target cells

http://kidshealth.org/teen/your_body/body_
basics/endocrine.html -Discusses the various
glands and their functions
Hypothalamus
Pituitary gland
 Pineal body
 Thyroid
 Parathyroid
 Pancreas
 Adrenals
 Ovaries and Testes



http://www.nlm.nih.gov/medlineplus/ency/
anatomyvideos/000048.htm
 Present
in the
brain and
produces
releasing
hormones and
inhibitory
hormones and
controls
information to
the pituitary
a small pea sizes gland
located in the center of
the skull, acting as the
Master Gland controlling
 Releases a number of
hormone that activate
other glands
 List some of them in
Journal noted in this
video


Pituitary gland video
medline plus
A structure of the
diencephalon
produces several
hormones including
Melatonin to influence
sleep-wake cycles and
sexual development.
 Connects the
endocrine system with
the Nervous system by
converting nerve
signals from PNS to
hormone signals

Located in the
neck ,
 Secretes T3 and
Thyroxine (T4) that
regulates
metabolism where
food is broken
down and
converted to heat
or energy
 Secretes Calcitonin
that plays a role in
calcium balance
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hypothalamus senses low levels of T3 and T4Sends message of Thyrotropin-releasing
hormone(TRH) to Pituitary gland to produce TSH
Pituitary send message to Thyroid of TSH
Thyroid get message increases production and
release of T3, T4
Blood levels rise.
Hypothalamus receives Info of increase levels
Communicates this to Pituitary
Pituitary sends message to thyroid to slow
production.
CYCLE CONTINUES
4 pea-sized glands on
the thyroid gland in the
neck.
 name is similar to
thyroid but glands are
completely different.
 Produce parathyroid
hormone (PTH), helps
balance calcium and
phosphorous. Which
play an important role
in muscle contraction
and nerve impulse

 Long
narrow
gland located in
the abdomen
behind the
stomach and in
front of the spine
 Secretes insulin,
glucagon to help
regulate the
body's use of
sugar


2 small glands located on
the top of each kidney
SOME Hormones Released
 ARE

corticosteroids- Cortisol
and Catecholamine's such
as dopamine, epinephrine
to increase HR and BP
during stress and
norepinephrine

Aldostrone that affects
kidney function by
controlling levels of salt
and water in the blood

Also small amounts of
Androgens
2
lobes Lies in
the lower part
of the neck or
upper chest
behind the
sternum
 Secretes
thymus
hormone
which plays an
important role
in the immune
system

Testes Male sex glands
that secrets androgens
that contribute to
production of sperm
and the development
of male characteristics

Ovaries release
hormone estrogen and
contribute to the
female characteristics
and regulate menstrual
cycle
 Once
a hormone is secreted,
it travels from the endocrine
gland that produced it
through the bloodstream to
the cells designed to receive
its message called target cells.
 target
cells have receptors that latch
onto only specific hormones, and that
hormone will communicate only with the
target cell that have receptors for that
hormone
 When the hormone reaches its target
cell, it locks onto the cell's specific
receptors
 The hormone-receptor combinations
transmit chemical instructions to the inner
workings of the cell.
Hormone receptors are found either exposed
on the surface of the cell or within the cell,
depending on the type of hormone.
 Three actions of hormones

› Endocrine action: the hormone is distributed in
blood and binds to distant target cells.
› Paracrine action: the hormone acts locally by
diffusing from its source to target cells in the
neighborhood.
› Autocrine action: the hormone acts on the same
cell that produced it.
When hormone levels reach a certain normal
amount, the endocrine system helps the body
to keep that level of hormone in the blood.

Example,

Thyroid Hormone Feedback Loop.
 Give
examples of disorders involving
hormones.
› Hypothyroidism
› Hyperthyroidism
› Cushing's Syndrome
› Addison’s disease
› Growth Hormone Deficiency- GHD
Thyroid does not produce
enough thyroid hormone.
 Symptoms include:
feeling tired and weak;
cold intolerance; dry skin
and brittle nails; and
constipation.
 Can raise your cholesterol
levels and can make you
more likely to have a
stroke or heart attack.
 It can be treated with
thyroid hormone pills.

Thyroid is producing too
much thyroid hormone.
 Common symptoms include:
excessive sweating; heat
intolerance; increased
bowel movements;
nervousness or agitation;
and weight loss with
increased appetite.
 Treatments include
antithyroid drugs; ablation
with radioactive iodine; or
surgery to partially remove
the thyroid.

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Results from excessive
production of Cortisol
from adrenal gland .
Can be the result of
tumor or drug therapy.
Symptoms include fat
deposition in face and
around shoulders.
(Buffalo hump)
Decreased Vit D
activity=bone loss
Emotional frailty.
Hirsuitism-hair growth on
face in females
Result from a
deficiency in Cortisol
production.
 Can be genetic or
the result of illness or
injury.
 Symptoms include
low blood pressure,
muscle weakness,
weight loss, and
hyperpigmentation
of skin.
 JFK suffered from this.

Different effects
depending on the age
of onset.
 In infants and childrenhypoglycemia and
growth failure.
 Rarely happens in
adults, but may
manifest as bone loss,
loss of muscle mass and
strength.
 Treated by
intramuscular injections
of HGH

Gary Coleman Little Rascals and Different Strokes and more

Use Inspiration to create a concept
map for Chemical Communication
describing the basic mechanism of
hormone action in the human body.

Share concept maps with class




(1) A loop system in which the system responds
to perturbation either in the same direction
(positive feedback) or in the opposite direction
(negative feedback).
(2) A process in which the level of one
substance influences the level of another
substance.
(3) A mechanism or a signal that tends to
initiate (or accelerate) or to inhibit (or slow
down) a process.
https://www.youtube.com/watch?feature=pla
yer_detailpage&v=_QbD92p_EVs -feedback
loop

2. How do hormones interact with target
cells?

3. What are examples of endocrine
glands and exocrine glands in the
human body?

4. How do feedback loops help regulate
the action of hormones?

5. How can too little or too much of a
hormone lead to disease?

Activity 2.3.2 Part 1 only

Need:
› White Poster Board
› Markers

What are his Symptoms

What organs and glands are effected

When your team thinks they have the correct
diagnosis- Get Part 2 from your teacher
Build the Pituitary Gland on your Manikin
 What is the connection between the
Pituitary Gland and the Hypothalamus
 Build the Thyroid Gland on your Manikin

The hypothalamus is part of the brain that lies just above the
pituitary gland. It releases hormones that start and stop the
release of pituitary hormones. The hypothalamus controls
hormone production in the pituitary gland through several
"releasing" hormones. It functions in maintaining homeostasis,
especially in coordinating the endocrine and nervous systems;
secretes hormones of the posterior pituitary and releasing
factors, which regulate the anterior pituitary.
 These include:

› Growth hormone-releasing hormone, or GHRH (controls GH
release)
› Thyrotropin-releasing hormone, or TRH (controls TSH release)
› Corticoptropin-releasing hormone, or CRH (controls ACTH
release)
› Another hormone made by the hypothalamus is gonadotropinreleasing hormone (GnRH). It tells the pituitary gland to
make luteinizing hormone (LH) and follicle-stimulating
hormone(FSH), which are important for normal puberty and
reproduction.




The pituitary gland is sometimes called the "master gland"
because of its great influence on the other body organs. Its
function is complex and important for overall well-being. It
produces hormones that act directly on the body and that
stimulate other endocrine glands to produce their own
hormones. The anterior pituitary (the front part of the pituitary)
produces several types of hormones:
Prolactin: stimulates milk production from a woman's breasts
after childbirth. In pregnant and breastfeeding women,
prolactin helps prevent ovulation (the release of eggs from
the ovaries).
Growth hormone (GH): GH stimulates growth in childhood
and is important for maintaining a healthy body composition.
In adults it is also important for maintaining muscle mass and
bone mass. GH also affects fat distribution in the body.
Adrenocorticotropin (ACTH): ACTH stimulates production of
cortisol by the adrenal glands. Cortisol, a so-called "stress
hormone," is vital to survival. It helps maintain blood pressure
and blood glucose levels, among other effects.


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

Thyroid-stimulating hormone (TSH): TSH stimulates the
thyroid gland to make thyroid hormones, which, in turn,
control (regulate) the body's metabolism, energy, growth
and development, and nervous system activity.
Luteinizing hormone (LH): LH regulates testosterone in men
and estrogen in women.
Follicle-stimulating hormone (FSH): FSH stimulates the
ovaries to release eggs (ovulate) in women. LH and FSH
work together to allow normal function of the ovaries or
testes, including sperm production.
The posterior pituitary (back part of the pituitary) produces
two hormones:
Oxytocin: Oxytocin causes milk to be released in nursing
mothers and contractions during childbirth.
Antidiuretic hormone (ADH): ADH, also called vasopressin,
regulates water balance. If ADH is not secreted in the right
amount, this can lead to too much or too little sodium
(salt) and water in the bloodstream.

http://www.skullbaseinstitute.com/video
_pituitary_tumor.htm

http://www.youtube.com/watch?featur
e=player_detailpage&v=-S_vQZDH9hY
Endocrine Gland
A gland (as the thyroid or the pituitary) that produces an endocrine secretion -- called
also ductless gland, gland of internal secretion.
Endocrine System
The glands and parts of glands that produce endocrine secretions, help to integrate and
control bodily metabolic activity, and include especially the pituitary, thyroid, parathyroid,
adrenals, islets of Langerhans, ovaries, and testes.
Exocrine Gland
A gland (as a sweat gland, a salivary gland, or a kidney) that releases a secretion
external to or at the surface of an organ by means of a canal or duct.
Gland
A cell, group of cells, or organ of endothelial origin that selectively removes materials from
the blood, concentrates or alters them, and secretes them for further use in the body or for
elimination from the body.
Glucagon
A protein hormone that is produced especially by the pancreatic islets of Langerhans and
that promotes an increase in the sugar content of the blood by increasing the rate of
breakdown of glycogen in the liver.
Hormone
Any one of the many circulating chemical signals found in all multicellular organisms that
are formed in specialized cells, travel in body fluids, and coordinate the various parts of
the organism by interacting with target cells.
Hypothalamus
The ventral part of the vertebrate forebrain; functions in maintaining homeostasis,
especially in coordinating the endocrine and nervous systems; secretes hormones of the
posterior pituitary and releasing factors, which regulate the anterior pituitary.
Insulin
A vertebrate hormone that lowers blood glucose levels by promoting the uptake of
glucose by most body cells and the synthesis and storage of glycogen in the liver.
Essential Question

1.How do humans communicate with
the world around them?





How does the Nervous System and Endocrine
System Communicate.
The hypothalamus connects these two important
communication systems.
The hypothalamus is a tiny collection of nuclei that is
responsible for controlling an astonishing amount of
behavior.
Hypothalamus located at the base of the forebrain,
regulates basic needs such as sleep, hunger, thirst and
sex in addition to emotional and stress responses.
hypothalamus controls the pituitary glands, which
controls the release of hormones from other glands in
the endocrine system

2. How does the power of sight allow humans to
communicate with the outside world?
A
dissociation
between
physical reality
and subjective
perception
 the visual illusion
is one of the
most important
tools used by
neuroscientists to
understand how
the brain creates
its sense of
reality.
 Optic
Nerve
 Sclera
 Cornea
 Anterior
Cavity
 Posterior Cavity
 Tapetum
 Choriod
 Optic Disc or
Blind Spot
 Pupil
 Aqueous
Humor
 Vitreous Humor
 Iris
 Ciliary Body
 Suspensory
Ligaments
 Lens

http://www.youtube.com/watch?feature=pl
ayer_embedded&v=0rbCrJoTatE -Cow Eye
Dissection

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
Cornea: the clear front window of the eye. The cornea transmits and
focuses light into the eye.
Iris: the colored part of the eye. The iris helps regulate the amount of
light that enters the eye.
Lens: the transparent structure inside the eye that focuses light rays
onto the retina.
Macula: a small area in the retina that contains special light-sensitive
cells. The macula allows us to see fine details clearly.
Optic Nerve: the nerve that connects the eye to the brain. The optic
nerve carries the impulses formed by the retina to the brain, which
interprets them as images.
Pupil: the dark center in the middle of the iris. The pupil determines
how much light is let into the eye. It changes sizes to accommodate
for the amount of light that is available.
Retina: the nerve layer that lines the back of the eye. The retina senses
light and creates impulses that are sent through the optic nerve to the
brain.
Vitreous: the clear, jelly-like substance that fills the middle of the eye.

3. How is light focused by the eye?

4. How do the eye and the brain work
together to process what we see?

5. How does what we see impact other
human body systems?
Accommodation
The automatic adjustment of the eye for seeing at different
distances affected chiefly by changes in the convexity of the
crystalline lens.
Astigmatism
A defect of an optical system (as a lens) causing rays from a
point to fail to meet in a focal point resulting in a blurred and
imperfect image.
Blind spot
The small circular area in the retina where the optic nerve
enters the eye that is devoid of rods and cones and is
insensitive to light.
Cone
Any of the conical photosensitive receptor cells of the
vertebrate retina that function in color vision.
Cornea
The transparent part of the coat of the eyeball that covers
the iris and pupil and admits light to the interior.
Depth Perception
The ability to judge the distance of objects and the spatial
relationship of objects at different distances.
Hyperopia
Iris
Lens
Myopia
Optic nerve
A condition in which visual images come to a focus behind
the retina of the eye and vision is better for distant than for
near objects -- called also farsightedness.
The opaque muscular contractile diaphragm that is
suspended in the aqueous humor in front of the lens of the
eye, is perforated by the pupil and is continuous peripherally
with the ciliary body, has a deeply pigmented posterior
surface which excludes the entrance of light except through
the pupil and a colored anterior surface which determines
the color of the eyes.
A curved piece of glass or plastic used singly or combined in
eyeglasses or an optical instrument (as a microscope) for
forming an image by focusing rays of light.
A condition in which the visual images come to a focus in
front of the retina of the eye because of defects in the
refractive media of the eye or of abnormal length of the
eyeball resulting especially in defective vision of distant
objects -- called also nearsightedness.
Either of the pair of sensory nerves that comprise the second
pair of cranial nerves, arise from the ventral part of the
diencephalon, form an optic chiasma before passing to the
eye and spreading over the anterior surface of the retina,
and conduct visual stimuli to the brain.
Pupil
The opening in the iris, which admits light into the interior of
the vertebrate eye; muscles in the iris regulate its size.
Refraction
The deflection from a straight path undergone by a light ray
or a wave of energy in passing obliquely from one medium
(as air) into another (as water or glass) in which its velocity is
different.
Retina
The sensory membrane that lines most of the large posterior
chamber of the vertebrate eye, is composed of several
layers including one containing the rods and cones, and
functions as the immediate instrument of vision by receiving
the image formed by the lens and converting it into
chemical and nervous signals which reach the brain by way
of the optic nerve.
Rod
Any of the long rod-shaped photosensitive receptors in the
retina responsive to faint light.

It is the ability to interpret the surrounding
environment by processing information
that is contained in visible light. The
resulting perception is also known as
eyesight, sight, or vision

Predict your dominant eye. Which eye do you think is
your dominant. Next, locate an object 8-10 feet
away. Keep both eyes open and hold your thumb
up at arms length. “Cover” the object with your
thumb. Now, close the right eye. If the thumb
appeared to move to the right, the right eye is
dominant. If the thumb did not seem to move, the
left eye is dominant. Poll the class to see how the
result matched their prediction.

Introduce optical illusions and depth perception by
showing hidden image stereograms. You can either
bring in books or have them view the online example
at the Magic Eye® site
http://www.magiceye.com/faq_example.htm.

Show DVD: Human Body: Pushing the
Limits DVD series. Chapter 2 – 1.11 on the
Sight DVD

http://www.allaboutvision.com/eyeexam/refraction.htm.
In pairs make your way through the
eleven stations.
 Only spend about 10 minutes in each
station
 You will need Activity 2.4.2: Student
Response Sheet


The retina of the eye
possesses two special
types of nerve cells known
as photoreceptors.
› Rods function in dim light
and perceive shades of
gray.
› Cones function in bright light
and provide sharp, colorful
images.

Impulses from rods and
cones pass through nerve
cells to the optic nerve.

There are three different types of cones:
› Red cones
› Blue cones
› Green cones
Each type of cone is sensitive to a different
range of wavelengths of light.
 Different types of cones function together
to interpret colors other than blue, red, and
green.
 If any of the cones malfunction, color
deficiency or color blindness occurs.

Depth perception is the ability to judge
the relative distances between objects in
three dimensions.
 With one eye, the field of vision appears
two-dimensional.
 With two eyes, the eyes see and the
brain processes different views of the
same object.

Two parts of the eye – the cornea and the
lens – focus light on the retina.
 The cornea does most of the work, but it
cannot change shape. Fine adjustments
are carried out by the lens.
 Accommodation is the combination of
reflex actions by which the lens of the eye
changes to keep the focal length, the
distance between the center of the lens
and its focal point, constant.
 Ciliary muscles in the eye assist adjustment
of the lens.





Astigmatism is a condition in which the cornea or
the lens is irregularly shaped.
This shape change causes incoming light rays to
refract and converge improperly.
The light rays do not focus at a specific point on
the retina, resulting in a blurry or distorted image.
Astigmatism may be corrected with eyeglasses,
contact lenses, or refractive surgery.
The optic nerve exits the eye at the
retina on its way to the brain.
 Since this area of the retina does not
have receptors that respond to light, it is
referred to as the blind spot. An image
that falls on this area can not be seen.
 Normally people do not recognize the
blind spot because the eyes are always
on the move and the brain ignores this
“hole” in visual input.

Peripheral vision is the ability to see things
that fall outside of the direct line of
vision.
 Due to their proximity to the edge of the
retina, rods are responsible for this
aspect of vision.
 Peripheral vision is better for detecting
movement than for processing sharp
images, and is most often stronger in the
dark.

Optical illusions are visual tricks that
actually take place in the brain rather
than the eye.
 The visual cortex of the brain deciphers
images sent from the eye, however
surrounding objects, intense colors,
distortions of expected patterns, and
preconceptions can cause the mind to
“see” and interpret an image differently.





Afterimages are optical illusions that occur
when looking away after staring intently at a
fixed image or color.
The constant light stimulating the retina causes
the cones in that area to become fatigued.
After looking away from the image, the lessstimulated cones, which are not fatigued, still
function.
The resulting image lasts briefly and because it
comes only from the less-fatigued cones, is
perceived as a negative image.


6. What is visual perception?
7. What does it mean to have 20/20
vision?

8.How can corrective lenses be used to
refocus light and resolve myopia and
hyperopia?

9. How does the eye perceive depth,
color and optical illusions?

http://www.exploratorium.edu/seeing/n
otfadeaway/site/quitdriving.html
RETINITIS
PIGMENTOSA
HYPEROPIA
MYOPIA
GLAUCOMA
REVIEW QUESTIONS

Refers to a group
of inherited
disorders that
slowly lead to
blindness due to
abnormalities of
the photoreceptors
in the retina.




near- sightedness
short-sightedness
A vision condition in which
close objects are seen
clearly, but objects farther
away appear blurred.
Myopia occurs if the
eyeball is too long or the
cornea, the clear front
cover of the eye, has too
much curvature. As a
result, the light entering the
eye isn’t focused correctly
and distant objects look
blurred.



A defect of vision caused by an
imperfection in the eye (often
when the eyeball is too short
lengthwise or when the lens
can’t become round enough
causing inability to focus on
near objects)
As an object approaches the
eye, the eye must increase its
power to keep the image in
focus on the retina.
In hyperopia the power of the
cornea and lens is insufficient so
the image appears blurred.

Glaucoma is an eye
disease that affects
the pressure of the
eye, resulting in optic
nerve damage. The
aqueous and
vitreous humor
expand, which then
covers the optic
nerve, which leads
to vision loss.
Glaucoma is the
second leading
cause of blindness.

10. How does an error in the structure or
function of the eye relate to disease or
dysfunction?

11. How is life impacted by a vision
disorder?

12. What are the tests and procedures in
a routine eye exam?

Part 1

Create a handout titled “What You
Need to Know about an Eye Exam”.

Career Journal:
› Opthamologist
› Optometrist
› Optician

Describe a Scenario of why a a patient
would see this type of eye doctor in
addition to the information listed on your
Career Journal Rubric.