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PHYSIOLOGY

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Title: PHYSIOLOGY


1
PHYSIOLOGY
  • Department of Physiology and Patophysiology

2
Course Description
  • The course will offer basic physiological
    knowledge necessary to understand the essential
    facts and concepts of human physiology, in order
    for you to be able to make clinical judgments on
    a rational scientific basis.
  • Course duration- 40 weeks,
  • Total course hours 220,
  • Lecture - 60 hours
  • experiment - 160 hours

3
BOOKS YOU MUST HAVE
  • THE TEXTBOOK OF PHYSIOLOGY BY GUYTON HALL,
    TENTH EDITION (2000)- REQUIRED!!!
  • REVIEW OF PHYSIOLOGY BY GANONG. TWENTYTH EDITION
    (2000)- HIGHLY RECOMMENDED!

4
About Exam
  • Assessment by final examination General Modul -
    (80 points)
  • Assessment by experimental practice
  • (120 points)

5
Chapter 1Introduction to Physiology
6
Conception of Physiology
  • What is Physiology ?
  • Simply put, physiology is the scientific
    discipline that seeks to understand the function
    of living organisms and their constituent parts.
  • The word itself is composed of two Greek roots
    physis (meaning nature) and logos (meaning study
    or science).

7
Division of Physiology
  • Plant Physiology
  • Bacterial Physiology
  • Animal Physiology
  • Human Physiology

8
Studying Physiology (Why?)
  • Exploring the living mass by questioning
    observations
  • Teleological Question - "Why does the XYZ exist?"
  • Mechanistic Question - "What does XYZ do?
  • For example Why dose a neuron has dendrites and
    axon? What does dendrite or axon do during a
    neuron excitation?

9
Solving Physiological Questions
  • The laboratory Component
  • Scientific Method (How)
  • a. Develop a hypothesis
  • b. Plan and implement an experimental
  • design
  • Define the variables of the
    hypothesis
  • c. Analysis of experimental results
  • d. Interpretation of results

10
Obviously
  • Development of physiology relies on the
    development of other discipline, such as anatomy,
    histology, biochemistry, physics, chemistry,
    molecular biochemistry and so on.

11
Physiology and Medicine
  • Def. of medicine-The science of diagnosing,
    treating, or preventing disease and other damage
    to the body or mind.
  • A definition of physiology requires a definition
    of life, at the point of life, there is a tight
    link between physiology and medicine.

12
Physiology is important foundation of
medical practice.
13
  • The purposes of study for medical students are as
    follows
  • To get basic sense of normal functions and
    its regulation of living organisms
  • To know how to update medical
  • knowledge via research

14
General concept of Physiology
  • Function is a form of living structure.
  • Functional unit is a smallest group of cells,
    united to perform a specific function (nephron,
    motor unit).
  • Physiological system is a union of the organs
    for a specified function (blood system,
    circulatory system, the system of external
    respiration)
  • Operating system is a temporary union of the
    organs and physiological systems for
    biologically useful effect to the body (gas
    transportation system - combining the systems of
    blood, circulatory, respiratory)
  • Functional state is a state of biological
    structures and functions of the organism as a
    whole at a particular time (state of calm, state
    of activity, state of rest)

15
Basic functional properties of the body
  • 1. Metabolism

2. Regulation
3. Homeostasis
4. Adaptation
5. Growth, development, reproduction
6. Irritability
16
Metabolism the sum of all the chemical reactions
in the body.
  • Metabolism is divided into two inter-related
    processes
  • Catabolism breaking down relatively complex
    molecules into simpler ones .
  • Yields energy
  • Anabolism building larger, more complex
    molecules from smaller, simpler ones.
  • Requires energy
  • energy coupling between catabolism and anabolism
    allows life to exist.

17
Metabolism assimilation
anabolism
  • Intake
  • Composition Consume energy
  • Decomposition Release energy
  • Excretory

18
  • Regulation the body's ability to carry out the
    regulation of physiological functions.
  • There are two mechanisms of regulation of
  • functions
  • nerve (by means of the nervous system)
  • humoral (by means of chemicals dissolved in
    body fluids).

19
Homeostasis
  • Maintenance of relatively constant internal
    conditions despite large fluctuations in the
    environment.

20
  • The concept of homeostasis was first articulated
    by the French scientist Claude Bernard
    (1813-1878) in his studies of the maintenance of
    stability in the milieu interior. The term itself
    was coined by American physiologist Walter
    Cannon, author of The Wisdom of the Body (1932).

21
Claude Bernard, a father of
experimental physiology in France, said
constancy of the internal environment is the
condition for free life.
22
Homeostatically maintained variables
  • Temperature
  • Ion concentrations
  • pH
  • Nutrient levels in body fluids and in storage
  • Gases

23
Adaptation
  • The purpose of adaptation - maintaining
    homeostasis of the organism in an environment
    that is constantly changing.
  • By the mechanism are distinguished
  • immediate adaptation
  • long-term adaptation.

24
Growth, development, reproduction
  • This physiological property provides self-healing
    and self-reproduction of organisms.

25
Irritability - the ability of biological
structures to move from a state of calm in the
active state under the influence of various
factors (irritants)
26
Classification of the irritants
  • 1 By the nature of power
  • Physical
  • Chemical
  • Biological
  • Social.
  • 2 By the biological features
  • adequate
  • inadequate
  • 3 By the power, the intensity of the action
  • sub-threshold
  • threshold
  • suprathreshold.

27
The laws of the irritation 
  • I The law of power relations
  • (the law of power)
  • The greater power of the stimulus, the greater
    (up to certain limits) biological response

Biological reaction
Threshold of stimulation
Maximum power
Power of the stimulus
28
  • ?? The law "all or nothing"
  • On the effect of subthreshold stimulus biological
    structure does not answer ("nothing"). On the
    effect of stimulus of the threshold power occurs
    once the maximum response ("all"). Further
    increase in stimulus force did not cause
    increased biological response.

Biologycal reaction
threshold of stimulation
Power of the stimulus
29
  • ??? The law of duration of the stimulation
  • (the law Power of time")
  • The greater power of the stimulus, the
    less time is neededso
  • that there was a biological reaction.

30
Structure of the cell membrane
Proteins - 55 Phospholipids - 25
cholesterol - 13 other lipids - 4
carbohydrates - 3 .
31
The basic lipid bilayer is composed of
phospholipid molecules. One end of each
phospholipid molecule is soluble in water that
is, it is hydrophilic. The other end is soluble
only in fats that is, it is hydrophobic. The
phosphate end of the phospholipid is hydrophilic,
and the fatty acid portion is hydrophobic. The
cholesterol molecules in the membrane are
also lipid in nature because their steroid
nucleus is highly fat soluble. These molecules,
in a sense, are dissolved in the bilayer of the
membrane. They mainly help determine the degree
of permeability (or impermeability) of the
bilayer to water-soluble constituents of body
fluids. Cholesterol controls much of the
fluidity of the membrane as well.
32
Two types of proteins occur integral proteins
that protrude all the way through the membrane,
and peripheral proteins that are attached only to
one surface of the membrane and do not penetrate
all the way through. Many of the integral
proteins provide structural channels (or pores)
through which water molecules and water-soluble
substances, especially ions, can diffuse between
the extracellular and intracellular fluids.These
protein channels also have selective
properties that allow preferential diffusion of
some substances over others. Other integral
proteins act as carrier proteins for transporting
substances that otherwise could not penetrate the
lipid bilayer. Sometimes these even
transport substances in the direction opposite to
their natural direction of diffusion, which is
called active transport. Still others act as
enzymes.
33
Integral membrane proteins can also serve as
receptors for water-soluble chemicals, such as
peptide hormones, that do not easily penetrate
the cell membrane. Interaction of cell membrane
receptors with specific ligands that bind to the
receptor causes conformational changes in the
receptor protein. This, in turn, enzymatically
activates the intracellular part of the protein
or induces interactions between the receptor and
proteins in the cytoplasm that act as second
messengers, thereby relaying the signal from the
extracellular part of the receptor to the
interior of the cell. In this way, integral
proteins spanning the cell membrane provide a
means of conveying information about
the environment to the cell interior. Peripheral
protein molecules are often attached to the
integral proteins. These peripheral proteins
function almost entirely as enzymes or as
controllers of transport of substances through
the cell membrane pores.
34
Membrane carbohydrates occur almost invariably
in combination with proteins or lipids in the
form of glycoproteins or glycolipids. The
carbohydrate moieties attached to the outer
surface of the cell have several important
functions (1) Many of them have a negative
electrical charge, which gives most cells an
overall negative surface charge that repels other
negative objects. (2) The glycocalyx of some
cells attaches to the glycocalyx of other cells,
thus attaching cells to one another. (3) Many of
the carbohydrates act as receptor substances for
binding hormones, such as insulin when
bound, this combination activates attached
internal proteins that, in turn, activate a
cascade of intracellular enzymes. (4)
35
Chemical compositions of extracellular and
intracellular fluids
36
Metabolism between the cell and its
microenvironment
Transmembranetransport
Vesiculartransport
Passive
Active
Endocytosis
Ectocytosis
Phagocytosis
Pinocytosis
Secretion
Excretion
Secondary
Primary
Filtration
Osmosis
Diffusion
Co-trans- port
Conter transport
37
Mechanism of pinocytosis
38
Mechanism of phagocytosis
39
Osmosis
Osmosis is the net diffusion of water (the
solvent) across the membrane. For osmosis to
occur, the membrane must be selectively permeable.
40
Filtration
41
Simple diffusion
Simple diffusion means that kinetic movement of
molecules or ions occurs through a membrane
opening or through intermolecular spaces without
any interaction with carrier Proteins in the
membrane.
42
Facilitated diffusion
Facilitated diffusion, like simple diffusion, is
powered by the thermal energy of the diffusing
molecules and involves net transport from the
side of higher to the side of lower
concentration. ATP is not required for either
facilitated or simple diffusion.
43
Primary active transport
Postulated mechanism of the sodium-potassium pump
A transport process, that pumps sodium ions
outward through the cell membrane of all cells
and at the same time pumps potassium ions from
the outside to the inside. The ATPase function of
the protein becomes activated.
44
Co-transport
Secondary active transport
45
Secondary active transport
Counter transport
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