The document provides an overview of the key concepts covered in the introduction to human anatomy and physiology, including:
1. It defines anatomy and physiology, and describes the different levels of structural organization in the human body from chemicals to organ systems.
2. It outlines the 11 major organ systems and their basic functions.
3. It discusses the basic life processes and physiological needs required to maintain life, including homeostasis, and the mechanisms by which the body maintains stable internal conditions.
INTRODUCTION TO HUMAN BODY - Definition and scope of anatomy and physiology, ...Kameshwaran Sugavanam
INTRODUCTION TO HUMAN BODY - Definition and scope of anatomy and physiology, levels of structural organization and body systems, basic life processes, homeostasis,
Introduction to HUMAN ANATOMY AND PHYSIOLOGYabhay joshi
THIS PRESENTATION INCLUDE THE INTRODUCTION TO HUMAN ANATOMY AND PHYSIOLOGY. IT INCLUDE DEFINITATION, STRUCTURAL LEVEL ORGANIZATION, BASIC LIFE PROCESSES AND BASIC ANATOMICAL TERMINOLOGY.
INTRODUCTION TO THE
HUMAN BODY
ANATOMY is the study of the structure of the
body and of the relationship of its constituent
parts to each other.
In regional anatomy a geographical study is
made and each region, e.g., arm, leg, head,
chest, etc., is found to consist of a number of
structures common to all regions such as bones,
muscles, nerves, blood vessels and so on.
From this study it follows that a number of
different systems exist.
Chapter-1 Introduction to Human Anatomy and PhysiologyD.R. Chandravanshi
Anatomy (Greek anatomē, 'dissection') is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science which deals with the structural organization of living things. It is an old science, having its beginnings in prehistoric times. Anatomy is inherently tied to developmental biology, embryology, comparative anatomy, evolutionary biology, and phylogeny, as these are the processes by which anatomy is generated, both over immediate and long-term timescales. Anatomy and physiology, which study the structure and function of organisms and their parts respectively, make a natural pair of related disciplines, and are often studied together. Human anatomy is one of the essential basic sciences that are applied in medicine.
INTRODUCTION TO HUMAN BODY - Definition and scope of anatomy and physiology, ...Kameshwaran Sugavanam
INTRODUCTION TO HUMAN BODY - Definition and scope of anatomy and physiology, levels of structural organization and body systems, basic life processes, homeostasis,
Introduction to HUMAN ANATOMY AND PHYSIOLOGYabhay joshi
THIS PRESENTATION INCLUDE THE INTRODUCTION TO HUMAN ANATOMY AND PHYSIOLOGY. IT INCLUDE DEFINITATION, STRUCTURAL LEVEL ORGANIZATION, BASIC LIFE PROCESSES AND BASIC ANATOMICAL TERMINOLOGY.
INTRODUCTION TO THE
HUMAN BODY
ANATOMY is the study of the structure of the
body and of the relationship of its constituent
parts to each other.
In regional anatomy a geographical study is
made and each region, e.g., arm, leg, head,
chest, etc., is found to consist of a number of
structures common to all regions such as bones,
muscles, nerves, blood vessels and so on.
From this study it follows that a number of
different systems exist.
Chapter-1 Introduction to Human Anatomy and PhysiologyD.R. Chandravanshi
Anatomy (Greek anatomē, 'dissection') is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science which deals with the structural organization of living things. It is an old science, having its beginnings in prehistoric times. Anatomy is inherently tied to developmental biology, embryology, comparative anatomy, evolutionary biology, and phylogeny, as these are the processes by which anatomy is generated, both over immediate and long-term timescales. Anatomy and physiology, which study the structure and function of organisms and their parts respectively, make a natural pair of related disciplines, and are often studied together. Human anatomy is one of the essential basic sciences that are applied in medicine.
Skeletal system
Divisions of skeletal system,
types of bone,
salient features and functions
of bones of axial and appendicular skeletal system Organization of skeletal muscle,
physiology of muscle contraction,
neuromuscular junction.
Cells and its components(Anatomy) Easy explanationSwatilekha Das
Cells and its components,discussion on cell membrane, cytoplasm, nucleus with pictures....
easy explanation of anatomy topic for 1 st year GNM & B.Sc nursing students...
Comment to get explanation on your required topics.....
please like and share and follow.....
Skeletal system
Divisions of skeletal system,
types of bone,
salient features and functions
of bones of axial and appendicular skeletal system Organization of skeletal muscle,
physiology of muscle contraction,
neuromuscular junction.
Cells and its components(Anatomy) Easy explanationSwatilekha Das
Cells and its components,discussion on cell membrane, cytoplasm, nucleus with pictures....
easy explanation of anatomy topic for 1 st year GNM & B.Sc nursing students...
Comment to get explanation on your required topics.....
please like and share and follow.....
Introduction to human body, Definition of anatomy and physiology and its branches, Levels of Structural Organization like Chemical level,
Cellular level, Tissue level, Organ level, Organ system level, Organismal level. Systems Of The Human Body like Integumentary System/ Exocrine System, Skeletal System, Muscular System, Nervous System, Endocrine system,
Cardiovascular system/circulatory system, Lymphatic system and immunity system,
Respiratory system,
Digestive system,
Urinary system and renal system,
Reproductive system and its structure and functions.
Characteristics of the living human organism, Basic life processes like Metabolism, Responsivenes, Movement, Growth, Differentiation, Reproduction. Homeostasis and Feedback system and its three basic components: Sensor, control center and an effector. Anatomical terminology like prone and supine position. Regional names lie Head, neck, trunk, upper and lower limbs.
Directional terms like Anterior and posterior. Planes and Sections like Sagittal plane, midsagittal or median plane, parasagittal, Frontal plane, Transverse or horizontal plane, Body Cavity like ventral and dorsal cavity, thoracic cavity and abdominopelvic cavity, cranial cavity and spinal cavity. Serous membrane like Parietal layer Visceral layer.
Abdominopelvic region and quadrants: four quadrants and nine areas like right upper, right lower, left upper, and left lower quadrants and the right hypochondriac, right lumbar, right illiac, epigastric, umbilical, hypogastric (or pubic), left hypochondriac, left lumbar, and left illiac divisions.
The Pharmacovigilance Programme of India is an Indian government organization which identifies and responds to drug safety problems. Its activities include receiving reports of adverse drug events and taking necessary action to remedy problems.
Human ear, organ of hearing and equilibrium that detects and analyzes sound by transduction (or the conversion of sound waves into electrochemical impulses) and maintains the sense of balance (equilibrium).
A disorder of the central nervous system that affects movement, often including tremors.
Nerve cell damage in the brain causes dopamine levels to drop, leading to the symptoms of Parkinson's.
Parkinson's often starts with a tremor in one hand. Other symptoms are slow movement, stiffness and loss of balance.
Treatment consists of medications to increase dopamine.
Neurotransmitters are chemical messengers that your body can't function without. Their job is to carry chemical signals (“messages”) from one neuron (nerve cell) to the next target cell. The next target cell can be another nerve cell, a muscle cell or a gland.
Hallucinogens are a type of drug that changes a person's perception of reality. Also known as 'psychedelic drugs', hallucinogens make a person see, feel and hear things that aren't real, or distort their interpretation of what's going on around them
endocrine system is made up of several organs called glands. These glands, located all over your body, create and secrete (release) hormones. Hormones are chemicals that coordinate different functions in your body by carrying messages through your blood to your organs, skin, muscles and other tissues
Stimulants work by acting on the central nervous system (CNS) to increase alertness and cognitive function. Stimulants can be prescription medications or illicit substances, such as Cocaine. Stimulants may be taken orally, snorted, or injected. If you have a Stimulant addiction, seek help today.
Local anaesthesia involves numbing an area of the body using a type of medicine called a local anaesthetic. These medicines can be used to treat painful conditions, prevent pain during a procedure or operation, or relieve pain after surgery
Myasthenia gravis is a chronic autoimmune, neuromuscular disease that causes weakness in the skeletal muscles (the muscles that connect to your bones and contract to allow body movement in the arms and legs, and allow for breathing).
Skeletal muscle relaxants are drugs that act peripherally at neuromuscular junction/ muscle fibre itself or centrally in the cerebrospinal axis to reduce muscle tone and/or cause paralysis. • A muscle relaxants is a drug that affects skeletal muscle function and decreases the muscle tone
A joint is a point where two bones make contact. Joints can be classified either histologically on the dominant type of connective tissue functionally based on the amount of movement permitted. Histologically the three joints in the body are fibrous, cartilaginous, and synovial.
DNA Gyrase Inhibitors -quinolones and Fluoroquinolones.pptxVijay Salvekar
DNA gyrase inhibitors of synthetic origin. Fluoroquinolones have been the most successful antibacterial agents targeting DNA gyrase. These compounds have been extensively explored and researched to improve spectrum of activity, potency and bacterial resistance.
biochemistry and pharmacology, receptors are chemical structures, composed of protein, that receive and transduce signals that may be integrated into biological systems
Anticonvulsants are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also increasingly being used in the treatment of bipolar disorder and borderline personality disorder, since many seem to act as mood stabilizers, and for the treatment of neuropathic pain.
Alzheimer's disease is a progressive neurologic disorder that causes the brain to shrink (atrophy) and brain cells to die. Alzheimer's disease is the most common cause of dementia — a continuous decline in thinking, behavioral and social skills that affects a person's ability to function independently.
Anti-anxiety medications help reduce the symptoms of anxiety, such as panic attacks or extreme fear and worry. The most common anti-anxiety medications are called benzodiazepines. Benzodiazepines are a group of medications that can help reduce anxiety and make it easier to sleep.
Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells.
Neurons (also called neurones or nerve cells) are the fundamental units of the brain and nervous system, the cells responsible for receiving sensory input from the external world, for sending motor commands to our muscles, and for transforming and relaying the electrical signals at every step in between.and A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse. The cell receiving the signal, any main body part or target cell, may be another neuron, but could also be a gland or muscle cell.
Skeletal muscle is one of the three significant muscle tissues in the human body. Each skeletal muscle consists of thousands of muscle fibers wrapped together by connective tissue sheaths. The individual bundles of muscle fibers in a skeletal muscle are known as fasciculi.
The muscular system is composed of specialized cells called muscle fibers. Their predominant function is contractibility. Muscles, attached to bones or internal organs and blood vessels, are responsible for movement. Nearly all movement in the body is the result of muscle contraction.
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
1. UNIT-I
Introduction
to
Anatomy and Physiology
Presented By:
Mr.Vijay Salvekar
Associate Professor
Dept.of Pharmacology
GRY Institute of Pharmacy, Borawan
(Syllabus,Scope,Organ system,levels of structural
organization, Homeostasis mechanism ,Basic
Anatomical terminology,Basic life process)
2.
3.
4.
5.
6.
7. HUMAN ANATOMY AND PHYSIOLOGY-I (Theory)
BP101T.
Unit I
• Introduction to human body
•Definition and scope of anatomy and physiology
•levels of structural organization and body systems
•basic life processes
•homeostasis
•basic anatomical terminology
8. • Anatomy – the study of the structure and shape of
the body and body parts & their relationships to one
another.
• The term anatomy comes from the Greek words
meaning to cut (tomy) apart ( ana) .
–Gross anatomy( macroscopic anatomy) – the
study of large, easily observable structures (by
naked eye), such as the heart or bone.
–Microscopic anatomy (cytology, histology) – the
study of very small structures, where a
magnifying lens or microscope is needed.
9. Physiology – the study of how the body and
its parts work or function
physio =nature
ology = the study of.
• Like anatomy , physiology has many
subdivisions.
• For example, neurophysiology explains the
working of the nervous system , and cardiac
physiology studies the function of the heart.
10. •Relationship between Anatomy and Physiology
•Anatomy and Physiology are always related .
Structure determines what functions can take
place
•For example, the lungs are not muscular
chambers like the heart and can not pump
blood, but because the walls of lungs are very
thin, they can exchange gasses and provide
oxygen to the body.
18. Levels of Structural Organization
The human body exhibits 6 levels of structural complexity :
1- Chemical level , the simplest level of structural ladder .At
this level atoms combine to form molecules such as water,
sugar, & proteins
2- Cellular level the smallest units of living things
3- Tissue level , groups of similar cells that have a common
function (4 basic types)
19. 4- Organ level, an organ is a structure composed of 2
or more tissue types that performs a specific function .
5- Organ System is a group of organs that work
together to accomplish a common purpose (each
organ has its own job to do)
6- Organismal level , represents the highest level of
structural organization( total of 11 organ systems)
20.
21. Body systems:The human body has 11 systems
1-INTEGUMENTARY
ORGANS
• Skin
FUNCTIONS
• Waterproofs, cushions, protects
deeper tissue
• Excretes salts & urea; pain, pressure
• Regulates body temp; synthesize
vitamin D
22. 2-SKELETAL SYSTEM
ORGANS
• Bones, cartilages, ligaments, joints
FUNCTIONS
• Protects & supports body organs
• Framework for muscles & movement
• Hematopoiesis; store minerals
23. 3- MUSCULAR SYSTEM
ORGANS
• Skeletal muscle (attached to bone)
FUNCTIONS
• Contraction & mobility
(locomotion)
• Facial expression, posture
• Produce body heat
24. 4- NERVOUS SYSTEM
ORGANS
• Brain, spinal cord, nerves, &
sensory receptors
FUNCTIONS
• Fast-acting central control system
• Responds to external/internal
stimuli via nerve impulses
(electrical messages)
25. 5- ENDOCRINE SYSTEM
ORGANS
• Pituitary, thyroid, parathyroids,
adrenals, thymus, pancreas,
pineal, ovaries, testes…..etc.
FUNCTIONS
• Slow -acting control system
• Glands produce hormones that
regulate growth, reproduction,
metabolism,…. etc.
26. 6- CIRCULATORY SYSTEM
ORGANS
• Heart, blood vessels, capillaries
&blood
FUNCTIONS
• Carries O2 nutrients, hormones, &
other substances to and from
tissue cells
• White blood cells protect against
bacteria, toxins, tumors
27. 7- LYMPHATIC SYSTEM
ORGANS
• Lymphatic vessels, lymph
nodes, spleen, tonsils
FUNCTIONS
• Complements circulatory system
by returning leaked fluid back to
blood vessels
• Cleanses the blood; involved in
immunity
28. 8- RESPIRATORY SYSTEM
ORGANS
• Nasal cavity, pharynx, larynx,
trachea, bronchi, & lungs
FUNCTIONS
• Keeps blood supplied with O2 &
removes CO2
• Carries out gas exchanges
through air sacs in lungs
29. 9- DIGESTIVE SYSTEM
ORGANS
• Oral cavity, esophagus,
stomach, small intestine, large
intestine, rectum, anus (liver &
pancreas)
FUNCTIONS
• Breaks food down into
absorbable units that enter the
blood; indigestible food
eliminated as feces
30. 10- URINARY (EXCRETORY) SYSTEM
ORGANS
• Kidney, ureter, urinary bladder,
urethra
FUNCTIONS
• Eliminates nitrogenous waste
from the body (urea & uric acid)
• Regulates water, electrolytes, &
acid-base balance of the blood
31. 11- REPRODUCTIVE SYSTEM
ORGANS
• Male
– Seminal vesicles, prostate,
penis, vas deferens, testis,
scrotum
• Female
– Ovaries, mammary glands,
uterus, vagina, uterine tube
FUNCTIONS
• Male – testes produce sperm &
male sex hormones
• Female – ovaries produce eggs &
female sex hormones; mammary
glands for nourishment
32. Maintaining Life
I-Necessary Life Functions : All living organisms
carry out certain vital functional activities necessary
for life, including :
1-Maintenance of boundaries: Every living organism
must maintain its inside distinct from outside.
-All the cells are surrounded by a selectively
permeable membrane.
-The body as a whole is enclosed and protected by the
integumentary system, or skin, which protects our
internal organs from drying out, bacteria, heat,
sunlight, and chemicals .
33. 2-Movement :
-It includes the activities promoted by the
muscular system , the skeletal system provides
the bony framework that the muscles pull on as
they work.
-Movement also occurs when substances such
as blood, foodstuffs, and urine are propelled
through internal organs .
- On the cellular level, the muscle cell’s ability to
move by shortening is more precisely called
contractility.
34. 3- Responsiveness or irritability, is the ability
to sense changes (stimuli) in the environment and
then respond to them.
-you involuntarily pull your hand away from the
painful stimulus .
-When carbon dioxide in your blood rises to
dangerously high levels, your breathing rate speeds
up.
Because nerve cells are highly irritable and
communicate rapidly with each other via electrical
impulses, the nervous system is most involved with
responsiveness. However, all body cells are irritable
to some extent.
35. 4-Digestion :is the breaking down of ingested
foodstuffs to simple molecules that can be
absorbed into the blood. The nutrient-rich
blood is then distributed to all body cells by the
cardiovascular system.
In a simple, one-celled organism such as an
amoeba, the cell itself is the “digestion
factory,” but in the multicellular human body,
the digestive system performs this function for
the entire body.
36. 5- Metabolism is a broad term that includes all
chemical reactions that occur within body cells. It
includes breaking down substances into their simpler
building blocks (catabolism), synthesizing more
complex cellular structures from simpler substances
(anabolism), and using nutrients and oxygen to
produce (via cellular respiration) ATP, that power
cellular activities.
Metabolism depends on the digestive and respiratory
systems to make nutrients and oxygen available to be
distributed throughout the body. Metabolism is
regulated largely by hormones secreted by endocrine
system glands.
37. 6- Excretion is the process of removing
excreta (ek-skre′tah), or wastes, from the body.
– The digestive system rids the body of
indigestible food residues in feces.
-The urinary system disposes of nitrogen-
containing metabolic wastes, such as urea, in
urine.
- Carbon dioxide, a by-product of cellular
respiration, is carried in the blood to the lungs,
where it leaves the body in exhaled air.
38. 7- Reproduction : is making a whole new person which
is the major task of the reproductive system.
- When a sperm unites with an egg, a fertilized egg
forms, which then develops into a baby within the
mother’s body.
- The reproductive system is regulated by hormones of
the endocrine system.
- Because males produce sperm and females produce
eggs (ova), there is a division of labor in the
reproductive process, and the reproductive organs of
males and females are different .
- The female’s reproductive structures provide the site
for fertilization of eggs by sperm, then protect and
nurture the developing fetus until birth.
39. 8- Growth is an increase in size of a
body part or the organism. It is usually
accomplished by increasing the number
of cells. However, individual cells also
increase in size when not dividing. For
true growth to occur, constructive
activities must occur at a faster rate than
destructive ones
40. II.Survival Needs
Survival needs include:
1-nutrients
Nutrients, taken in via the diet, contain the chemical
substances used for energy and cell building.
-Carbohydrates are the major energy fuel for body cells.
-Proteins, and to a lesser extent fats, are essential for building
cell structures.
- Fats also provide a reserve of energy-rich fuel.
- Selected minerals and vitamins are required for the
chemical reactions that go on in cells and for oxygen transport
in the blood. The mineral calcium helps to make bones hard
and is required for blood clotting.
41. 2- Oxygen : All the nutrients in the world are
useless unless oxygen is also available. Because
the chemical reactions that release energy from
foods are oxidative reactions that require
oxygen, human cells can survive for only a few
minutes without oxygen. Approximately 20% of
the air we breathe is oxygen. It is made available
to the blood and body cells by the cooperative
efforts of the respiratory and cardiovascular
systems.
42. 3- Water accounts for 60–80% of body
weight and is the single most abundant
chemical substance in the body. It provides the
watery environment necessary for
chemical reactions and the fluid base for
body secretions and excretions. Water is
obtained chiefly from ingested foods or
liquids and is lost from the body by
evaporation from the lungs and skin and
in body excretions.
43. 4- If chemical reactions are to continue at life-
sustaining rates, normal body temperature
must be maintained. As body temperature
drops below 37°C (98.6°F), metabolic
reactions become slower and slower, and
finally stop. When body temperature is too
high, body proteins lose their characteristic
shape and stop functioning. At either extreme,
death occurs. Most body heat is generated by the
activity of the muscular system.
44. 5- Atmospheric pressure is the force that air exerts on
the surface of the body. Breathing and gas exchange in
the lungs depend on appropriate atmospheric pressure.
At high altitudes, where atmospheric pressure is lower
and the air is thin, gas exchange may be inadequate to
support cellular metabolism.
Notice :The mere presence of these survival factors is
not sufficient to sustain life. They must be present in
appropriate amounts; excesses and deficits may be equally
harmful. For example, the food we eat must be of high
quality and in proper amounts; otherwise, nutritional
disease, obesity, or starvation is likely.
45. Homeostasis
• Describes the body’s ability to
maintain relatively stable internal
conditions even though the
outside world is continuously
changing
• The literal translation of
homeostasis is “unchanging,”(
homeo= the same, stasis =
standing still which is not true).
46. The term does not really mean a
static, or unchanging, state. Rather,
it indicates a dynamic state of
equilibrium, or a balance, in which
internal conditions vary, but always
within relatively narrow limits. In
general, the body is in homeostasis when its
needs are adequately met and it is functioning
smoothly.
47. Homeostatic Control Mechanisms
Communication within the body is essential
for homeostasis.
Communication is accomplished chiefly by
the nervous and endocrine systems, which
use neural electrical impulses or blood borne
hormones, respectively, as information
carriers.
Regardless of the factor being regulated(the
variable)all homeostatic control mechanisms
have at least three interdependent
components .
48. The first component, the receptor, is some
type of sensor that monitors the
environment and responds to changes,
called stimuli, by sending information (input)
to the second component, the control
center. Input flows from the receptor to
the control center along the so-called
afferent pathway. The control center,
analyzes the input it receives and then
determines the appropriate response or
course of action.
49. The third component, the effector,
provides the means of response (output) to
the stimulus. Information flows from the
control center to the effector along the
efferent pathway. The results of the
response then feed back to influence the
stimulus, either depressing it (negative
feedback) so that the whole control
mechanism is shut off or enhancing it
(positive feedback) so that the reaction
continues at an even faster rate.
50.
51. • Homeostatic control mechanisms
are TWO:
–Negative feedback mechanisms – the
net effect of the response to the
stimulus is the shut off of the original
stimulus or to reduce its intensity
• E.g. – body temp, blood chemical
levels
–Positive feedback mechanisms –
tend to increase the original
disturbance (stimulus) and push the
variable farther from its original value
52. Negative Feedback Mechanisms
Most homeostatic control mechanisms are
negative feedback mechanisms. In these
systems, the output shuts off the original
stimulus or reduces its intensity. These
mechanisms cause the variable to change in a
direction opposite to that of the initial
change, returning it to its “ideal” value; thus
the name “negative” feedback mechanisms.
53. A good example of a nonbiological negative
feedback system is a home heating system
connected to a temperature-sensing
thermostat . If the thermostat is set at 20°C
(68°F), the heating system (effector) is
triggered ON when the house temperature
drops below that setting. As the furnace
produces heat and warms the air, the
temperature rises, and when it reaches 20°C
or slightly higher, the thermostat triggers the
furnace OFF.
54. This process results in a cycling of
“furnace-ON” and “furnace-OFF”
so that the temperature in the house
stays very near the desired
temperature of 20°C. Your body
“thermostat,” located in a part of
your brain called the hypothalamus,
operates in a similar fashion.
55. Positive Feedback Mechanisms
In positive feedback mechanisms, the result
or response enhances the original stimulus
so that the activity (output) is accelerated.
This feedback mechanism is “positive”
because the change that occurs proceeds in
the same direction as the initial disturbance,
causing the variable to deviate further and
further from its original value or range.
56. In contrast to negative feedback controls,
which maintain many physiological
functions or keep blood chemicals within
narrow ranges, positive feedback
mechanisms usually control infrequent
events that do not require continuous
adjustments. However, TWO familiar
examples of their use as homeostatic
mechanisms are the enhancement of labor
contractions during birth and blood clotting.
57. The body’s ability to regulate its internal
environment is fundamental, and all
negative feedback mechanisms have the
same goal: preventing sudden severe
changes within the body. Body temperature
and blood volume are only two of the
variables that need to be regulated. There are
hundreds! Other negative feedback
mechanisms regulate heart rate, blood
pressure, the rate and depth of breathing,
and blood levels of oxygen, carbon
dioxide, and minerals.
58. Homeostatic Imbalance
Homeostasis is so important that most disease can be
regarded as a result of its disturbance, a condition
called homeostatic imbalance. As we age, our body’s
control systems become less efficient, and our internal
environment becomes less and less stable. These events
increase our risk for illness and produce the changes we
associate with aging.
Examples of homeostatic imbalance are provided
throughout this course to enhance understanding of
normal physiological mechanisms.
62. Directional terms
• Superior (cranial or cephalad) – toward the
head end or upper part of a structure or body;
above
• Inferior (caudal) – away from the head end or
toward the lower part of a structure or body;
below
• Anterior (ventral) – toward or at the front of the
body; in front of
• Posterior (dorsal) – toward or at the backside
of the body; behind
• Medial – toward or at the midline of the body; on
the inner side of
• Lateral – away from the midline of the body; on
63.
64.
65.
66.
67. • Proximal – close to the origin of the
body part or the point of attachment
of a limb to the body trunk.
• Distal – farther from the origin of a
body or the point of attachment of a
limb to the body trunk.
• Superficial (external) – toward or at
the body surface.
• Deep (internal) – away from the
body surface; more internal.
68.
69. Body planes and sections
A section is a cut made along a plane
• Sagittal – cut made along the lengthwise or
longitudinal plane of the body dividing it into left
and right parts
• Midsagittal (median) plane – right and left
parts are of equal size
• Frontal (coronal) plane – cut made along a
lengthwise plane that divides the body into
anterior and posterior parts
• Transverse plane (cross section) – cut made
along a horizontal plane dividing the body or
organ into superior and inferior parts
70. Planes
• Sagittal Plane –
divides body into right
and left parts.
• Midsagittal =median
plane –divides body
into two equal halves.
71. Planes
• Frontal = coronal
plane – divides body
into anterior and
posterior parts
73. Regional terms
There are many visible
landmarks on the surface of the
body:
- Anterior body landmarks
- Posterior body landmarks
74. Body Cavities
There are two sets of internal body cavities called
the dorsal and ventral body cavities. These
cavities are closed to the outside.
1-Dorsal Body Cavity
Which protects the fragile nervous system organs
has two subdivisions. The cranial cavity, in the
skull, encases the brain. The vertebral, or spinal,
cavity, which runs within the bony vertebral
column, encloses the delicate spinal cord. The
cranial and spinal cavities are continuous with one
another
75. 2- Ventral Body Cavity
The more anterior and larger of the closed body
cavities is the ventral body cavity .It has two major
subdivisions, the thoracic and the abdominopelvic
cavities. It houses internal organs collectively called the
viscera .
They are separated by the diaphragm, a dome-shaped
muscle important in breathing.
The abdominopelvic cavity, as its name suggests, has
two parts not physically separated by a muscular or
membrane wall.
The inferior part, the pelvic cavity, lies in the bony
pelvis .