my physiology presentation

1. “
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HOMEOSTASIS
P R E S E N T E D B Y :
N O O R A F S H A N
R O L L N O # B M - 2 0 1 8 - 8 6
M A R I A S O H A I L
R O L L N O # B M - 2 0 1 8 - 8 6
M A H E E N M E H M O O D
R O L L N O # B M - 2 0 1 8 - 8 6
L A R A I B
R O L L N O # B M - 2 0 1 8 - 8 6

2. HOMEOSTASIS
3. FEED BACK MECHANISM
AND HOW
HOMEOSTATIC CONTROL
MECHANISMS
WORK?
1. LEVELS OF
ORGANIZATION IN THE
BODY &
INTRODUCTION TO
HOMEOSTASIS
2. ALL ORGANS
AND ORGAN
SYSTEMS OF
THE BODY HELP IN
MAINTENANCE OF
HOMEOSTASIS
4. WHAT IF
HOMEOSTASIS
FAILS?
AND ITS
CONDITIONS

3. •The cell is the basic unit of both
structure and function in a living being
and is the smallest unit capable of
carrying out the processes associated
with life
• The tissues are group of cells of
similar specialization
• An organ is unit made up of several
tissue types
• A body system is a collection of
related organs
• The body systems are packaged
together into a functional whole
body(Organism)
•Organisms are independent living
entities
LEVELS OF
ORGANIZATION IN THE
BODY: • Intracellular fluid—fluid contained
within all of the cells of the body
• Extracellular fluid—fluid outside the
cells of the body and is the internal
environment in which the cells live . It is
composed of plasma and interstitial
fluid
Concept of Extracellular
and Intracellular fluid

4. It is the tendency to resist change in order
to maintain a stable, relatively constant
internal environment.
“
”

5. WHAT NEEDS TO BE
MAINTAINED CONSTANT
IN INTERNAL
ENVIRONMENT?
1. Concentration of
oxygen and carbon
dioxide.
2. 2. pH of the internal
environment.
3. Concentration of
nutrients and waste
products.
4. Concentration of salt
and other electrolytes.
5. Volume and pressure of
extracellular fluid.
A FEEDBACK SYSTEM
CONSISTS OF THREE
COMPONENTS:
SENSOR (RECEPTOR): detects specific
changes (stimuli) in the environment.
INTEGRATOR: act to direct impulses to
the place where a response can be
made.
EFFECTOR: performs the appropriate
response.

6. FEED BACK MECHANISM:
EXAMPLES:
A feedback mechanism is a cycle in which the output
of a system “feeds back” to either modify or
reinforce the action taken by the system.
Feedback mechanism can be:
•Negative feedback (more common)
• Positive feedback
Acid-Base Balance
When the number of acidic compounds in the blood
increases, body acidity also increases.
Body Temperature
Normal body temperature is 37 degrees C or 98.6
degrees F.
Fluid Volume
it must regulate the loss and gain of fluid. Hormones help
to regulate this balance by causing the excretion or
retention of fluid.
Glucose Concentration
Glucose concentration– blood
sugar – present in the
bloodstream. The body uses
glucose as a source of energy,
but too much or too little
glucose in the bloodstream
can cause serious
complications.
Calcium Levels
The bones and teeth contain
approximately 99 percent of
the calcium in the body, while
the other 1 percent circulates
in the blood. Too much
calcium in the blood and too
little calcium in the blood both
have negative effects.
1.
2.

7. P O S I T I V E F E E D B A C K :
Positive feedback involves a response
that reinforces the change detected (it
functions to amplify the change)
A change is detected by a receptor and
effectors is activated to induce the same effect
– this promotes further change
Positive feedback loops will continue to amplify
the initial change until the stimulus is removed
C H I L D B I R T H – stretching of uterine walls
cause contractions that further stretch the
walls (this continues until birthing occurs)
L A C TAT I O N – the child feeding stimulates
milk production which causes further feeding
(continues until baby stops feeding)
O V U L AT I O N – the dominant follicle
releases oestrogen which stimulates LH and
FSH release to promote further follicular
growth
B L O O D C L O T T I N G – platelets release
clotting factors which cause more platelets to
aggregate at the site of injury

8. N E G AT I V E F E E D B A C K
Negative feedback involves a response that is
the reverse of the change detected (it
functions to reduce the change)
A change is detected by a receptor and an
effector is activated to induce an opposite
effect – this promotes equilibrium
T H E R M O R E G U L AT I O N
if body temperature changes, mechanisms are
induced to restore normal levels
B L O O D S U G A R R E G U L AT I O N
insulin lowers blood glucose when levels
are high ; glucagon raises blood glucose
when levels are low
O S M O R E G U L AT I O N
ADH is secreted to retain water when
dehydrated and its release is inhibited
when the body is hydrated

9. Cardiovascular
system
Respiratory
system
Nervous
system
Endocrine
system
Gastrointestina
l system
Excretory
system
Skeletal system
Integumenta-ry
system
Reproductive
system
ALL ORGANS
AND ORGAN
SYSTEMS OF
THE BODY
HELP IN
MAINTENANCE
OF
HOMEOSTASIS

10. •Transports oxygen, carbon dioxide, nutrients
and hormones to and from the body cells.
•Helps regulate pH and temperature.
•Provides protection against diseases.
C A R D I O VA S C U L A R
S Y S T E M :
R E S P I R ATO RY S Y S T E M :
•Exchange the gases between atmospheric air
and blood.
•Help adjust the pH of the body fluids.

11. S K E L E TA L S Y S T E M :
•Bones provide support, protection, the
production of blood cells.
•Muscles produce body movements and
produce heat to maintain the body
temperature.
I N T E G U M E N TA R Y S Y S T E M :
• Contributes to homeostasis by protecting the
body and helping regulate the body
temperature.
•It also allows you to sense pleasurable, painful
and other stimuli in your external
environment.

12. R E P R O D U C T I V E
S Y S T E M :•Sometimes reproduction is not
considered a homeostatic function.
• Helps maintain homeostasis by
generating new beings to take the
place of those that are dying and thus
help in maintaining the continuity of
life.
I N M A L E :
•The reproductive
system maintains homeostasis in the
male by regulating the overall temperature
of the testis.
•The reproductive system helps
maintain homeostasis in the female
body by regulating the vagina pH.
I N F E M A L E :

13. N E R V O U S S Y S T E M :
E N D O C R I N E S Y S T E M :
•Regulates the activity and growth of target
cells in the body.
• Regulate metabolism
•The endocrine system plays an important
role in homeostasis because hormones
regulate the activity of body cells.
•The release of hormones into the blood is
controlled by a stimulus. For example, the
stimulus either causes an increase or a
decrease in the amount of hormone
secreted.
•Generates nerve impulses (Action Potential)
that provide communication and regulation of
most body tissues.
•A major function of the nervous system is to
control the relative constancy of the internal
environment of the organism

14. •E X C R E TO R Y S Y S T E M :
G A S T R O I N T E S T I N A L
S Y S T E M :
• Breaks down food into absorbable form.
• Absorbs various nutrients.
• Eliminates waste from the body.
•The gastrointestinal tract is the largest
immune inter- face with the environment.
•Helps eliminate the waste products from
the body.
•Maintains the blood pH, volume,
pressure, osmolarity, electrolyte
composition etc.
•Produces hormones.

15. W H AT I F H O M E O S TA S I S FA I L S :
A failure of homeostasis – the balance of essential physiological states – can mean
disaster for an organism. If your body temperature falls too low or goes too high, you
might experience hypothermia or heatstroke, which can both be life-threatening.
The pancreas is one of the most
important organs involved in
maintaining energy homeostasis
because it is responsible for the
secretion of insulin and glucagon.
Insulin and glucagon are two counter
regulatory hormones that control the
systemic concentration of glucose, a
metabolic intermediate used by cells as
the primary source of energy. If glucose
homeostasis is thrown off balance, a
diabetic state develops.
D I A B E T E S :

16. H Y P O C A L C E M I A :
is an electrolyte imbalance
and is indicated by a low
level of calcium in the blood.
The normal adult value for
calcium is 4.5-5.5 mEq/L.
Calcium is important for
healthy bones and teeth, as
well as for normal muscle
and nerve function.
can occur from
hyperparathyroidism.
H Y P E R P H O S P H AT E M I
AHyperphosphatemia is an
electrolyte disorder in which
there is an elevated level of
phosphate in the blood. Most
people have no symptoms while
others develop calcium deposits
in the soft tissue. Often there is
also low calcium levels which can
result in muscle spasms.
H Y P O N AT R E M I A
can be caused by
excessive water intake,
excessive vomiting, or
aldosterone deficiency.
Hyponatremia is a low
sodium concentration in
the blood.
H Y P E R N AT R E M I A
can be caused by excessive
sodium in diet or with
dehydration
Hypernatremia is a common
electrolyte problem that is
defined as a rise in serum
sodium concentration to a
value exceeding 145 mmol/L.

17. R E S P I R ATO RY A L K A L O S I S
It is a disturbance in acid and base balance due to alveolar hyperventilation. Alveolar
hyperventilation leads to a decreased partial pressure of arterial carbon dioxide (PaCO2).
can be caused by oxygen deficiency at high altitude, stroke, or severe anxiety.
M E TA B O L I C A L K A L O S I S
I t is a metabolic condition in which the pH of tissue is elevated beyond the normal range
(7.35–7.45). This is the result of decreased hydrogen ion concentration, leading to
increased bicarbonate, or alternatively a direct result of increased bicarbonate
concentrations.
M E TA B O L I C A C I D O S I S
It is a condition that occurs when the body produces excessive quantities of acid or when
the kidneys are not removing enough acid from the body. Can be caused by actual loss of
bicarbonate ions, ketosis, or failure of kidneys to excrete H+.
WAT E R I N T O X I C AT I O N
It also known as water poisoning, hyper hydration, over hydration, or water toxemia is a
potentially fatal disturbance in brain functions that results when the normal balance of
electrolytes in the body is pushed outside safe limits by excessive water intake.

18. THE END.
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YOU!