CHAPTER 1: HUMAN ORGANISM
PHYSIOLOGY
INTRODUCTION
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ANATOMY AND PHYSIOLOGY
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Provides the basic knowledge about the
human body.
Helps us understand clearly the
fundamental concepts on how our body
functions well.
Importance of Anatomy and Physiology
Investigates processes and functions
Types of Physiology
1. Human Physiology – studies scientific
organism, the human
2. Systemic Physiology – studies body
organ-systems
3. Cellular Physiology – studies body cells
STRUCTURAL & FUNCTIONAL ORGANIZATION
Understand how the body responds to:
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atoms, molecule, organelle, cell, tissue, organ,
organ system, organism
stimuli
environmental changes
environmental cues
diseases
injuries
ANATOMY
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Investigates body structure
The term means to dissect
Types of Anatomy
1. Systemic
• Studies body organ-systems
2. Regional
• studies body regions (medical schools)
3. Surface anatomy
• Studies external features, for example,
bone projections
4. Anatomical imaging
• Using technologies (x-rays, ultrasound,
MRI)
5. Gross anatomy
• Study of large, easily observable
structures, such as the heart or bone
6. Microscopic anatomy
• Study of very small structures, where
magnifying lens or microscope is
needed
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this publication may be reproduced or distributed in any
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ALEXIS JADE V. BATICA | BSN-1 NH
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1. Chemical level – atoms (colored balls)
combine to form molecules.
2. Cell level – molecules form organelles,
such as the nucleus and mitochondria,
which make up cells.
3. Tissue level – similar cells and surrounding
materials make up tissue.
4 basic tissue types:
epithelial, connective, muscle, and nervous
4. Organ level – different tissues combine to
form organs, such as the urinary bladder.
5. Organ system level – organs, such as the
urinary bladder and kidneys, make up an
organ system.
6. Organism level – organ systems make up
an organism.
MAJOR ORGANS OF THE BODY
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of America. Previous editions © 2014, 2011,
and 2008. No part of this publication may be
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1. Brain – its function includes muscle control
and coordination, sensory reception and
integration, speech production, memory
storage, and elaboration of thoughts and
emotion.
2. Lungs – two sponge-like and cone-shaped
structures that fill most of the chest cavity.
Their essential function is to produce or
provide oxygen from inhaled air to the
bloodstream and to the exhaled carbon
dioxide.
3. Liver – its main function is to process the
contents of the blood to ensure composition
remains the same. This process involves
breaking down fats producing urea filtering
harmful substances and maintaining a
proper level of glucose in the blood.
4. Bladder – it stretches to store urine and
contracts to release urine.
5. Kidneys – their function is to maintain the
body’s chemical balance by excreting waste
products and excess fluid in the form of urine.
6. Heart – a hollow muscular organ that pumps
blood through the blood vessels by repeated
rhythmic contractions.
7. Stomach – its main purpose is digestion of
food through production of gastric juices
which break down, mix, and churn the food
into a thin liquid.
8. Intestines – divided into major sections: the
small intestine and the large intestine. The
function of the small intestine is to absorb
most ingested food. The large intestine is
responsible for absorption of water and
excretion of solid waste material.
9. Gallbladder – it contains cholesterol, bile
salts, bile, and bilirubin. In a healthy person,
the liver releases bile into the gallbladder
which the gallbladder stores and then
releases to travel down the common bile duct
into the small intestine to aid digestion.
10. Pancreas – it functions as both an exocrine
gland and endocrine gland. As an exocrine
gland, it produces enzymes (amylase, lipase,
trypsin, and cytotrypsin) a person needs to
help digest their food and convert it into
energy. As an endocrine gland, it produces
and releases insulin which helps the body
remove glucose from the blood and convert
it into energy.
11. Spleen – it stores and filters blood and
makes white blood cells that protect you from
infection.
12. Spinal cord – it connects your brain to your
lower back. It carries nerve signals from your
brain to your body and vice versa. These
nerve signals help you feel sensations and
move your body. Any damage to your spinal
cord can affect your movement or function.
ALEXIS JADE V. BATICA | BSN-1 NH
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ORGAN SYSTEMS OF THE BODY
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United States of America. Previous editions © 2014, 2011, and 2008. No part of
this publication may be reproduced or distributed in any form or by any means, or
stored in a database or retrieval system, without the prior written consent of
McGraw-Hill Education.
ALEXIS JADE V. BATICA | BSN-1 NH
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CHARACTERISTICS OF LIFE
1. Organization – functional interrelationships
between parts
2. Metabolism – sum of all chemical and
physical changes sustaining an organism;
ability to acquire and use energy in support
of these changes
3. Responsiveness – ability to sense and
respond to environmental changes; includes
both internal and external environments
4. Growth – can increase in size; size of cells,
group of cells, extracellular materials
5. Development – changes in form and size;
changes in cell structure and function from
generalized to specialized – differentiation
6. Reproduction – formation of new cells or
new organisms; generation of new
individuals; tissue repair
Survival Needs
1. 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 fat,
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.
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 body cells by the cooperative
efforts
of
the
respiratory
and
cardiovascular systems.
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.
• 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.
4. Normal Body Temperature
• If chemical reactions are to continue at
life-sustaining rates, it 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 hear is generated by the
activity of the muscular system.
5. Atmospheric Pressure
• Is the force that air exerts in 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.
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HOMEOSTASIS
- Maintenance of constant internal environment
despite fluctuations in the external or internal
environment.
Variables:
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Measures of body properties that may
change in value
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Example of variables:
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Positive feedback – mechanisms occur when the
initial stimulus further stimulates responses.
body temperature
heart rate
blood pressure
blood glucose levels
blood cell counts
respiratory rate
system response causes progressive
deviation away from the point
outside of normal range
not directly used for homeostasis
some positive feedback occurs under normal
conditions e.g., childbirth
generally associated with injury, disease
negative feedback mechanisms unable to
maintain homeostasis
Comparison of negative feedback and positive
feedback
Normal range: normal extent of increase or
decrease around a set point
Set point: normal, or average value of a
variable over time, body temperature
fluctuates around a set point.
Set points for some variables can be temporarily
adjusted depending on body activities, as needed:
Examples
body temperature
heart rate,
blood pressure,
respiratory rate
Common cause of
change
fever
exercise
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Anatomical position:
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Negative feedback – the main mechanism used
homeostatic regulation. It involves:
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TERMINOLOGY AND THE BODY PLAN
person standing erect with face and palms
forward
all relational descriptions based on the
anatomical position, regardless of body
orientation
detection – of deviation away from set point;
and
correction – reversal of deviation toward set
point and normal range
The components of feedback:
1. Receptor – detects changes in variable
2. Control center – receives receptor signal;
establishes set point; sends signal to effector
3. Effector – directly causes change in variable
Copyright © 2017 by McGraw-Hill
Education. All rights reserved. Printed
in the United States of America.
Previous editions © 2014, 2011, and
2008. No part of this publication may be
reproduced or distributed in any form or
by any means, or stored in a database
or retrieval system, without the prior
written
consent
of
McGraw-Hill
Education.
ALEXIS JADE V. BATICA | BSN-1 NH
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DIRECTIONAL TERMS
Copyright © 2017 by McGraw-Hill Education. All
rights reserved. Printed in the United States of
America. Previous editions © 2014, 2011, and
2008. No part of this publication may be
reproduced or distributed in any form or by any
means, or stored in a database or retrieval
system, without the prior written consent of
McGraw-Hill Education.
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Medial – close to midline
Lateral – away from midline
Proximal – close to point of attachment
Distal – far from point of attachment
Superficial – structure close to the surface
Deep – structure toward the interior of the
body
Superior – above
Inferior – below
Anterior – front (ventral)
Posterior – back (dorsal)
Planes of Section through an Organ
Note: in four-legged animals, the terms ventral
(belly) and dorsal (back) correspond to anterior and
posterior in humans.
BODY PLANES
Sagittal plane – separates the body into right and left
parts
Median plane – a sagittal plane along the midline
that divides body into equal left and right halves
Transverse plane – a horizontal plane that separates
the body into superior and inferior parts
Copyright © 2017 by McGraw-Hill Education. All
rights reserved. Printed in the United States of
America. Previous editions © 2014, 2011, and
2008. No part of this publication may be
reproduced or distributed in any form or by any
means, or stored in a database or retrieval
system, without the prior written consent of
McGraw-Hill Education.
Frontal plane – a vertical plane that separates the
body into anterior and posterior parts
ALEXIS JADE V. BATICA | BSN-1 NH
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BODY REGIONS
BODY CAVITIES
Copyright © 2017 by McGraw-Hill
Education. All rights reserved.
Printed in the United States of
America. Previous editions ©
2014, 2011, and 2008. No part of
this
publication
may
be
reproduced or distributed in any
form or by any means, or stored in
a database or retrieval system,
without the prior written consent of
McGraw-Hill Education.
Thoracic cavity
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space within chest wall and diaphragm
contains heart, lungs, thymus gland,
esophagus, trachea
Mediastinum
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space between lungs
contains
heart,
thymus
esophagus, trachea
gland,
SEROUS MEMBRANES
Upper limbs – upper arm, forearm, wrist, hand
Lower limbs – thigh, lower leg, ankle, foot
Central region – head, neck, trunk
Structure:
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visceral serous membrane covers
organs
parietal serous membrane is the outer
membrane
cavity – a fluid-filled space between the
membranes
3 sets of serous membranes and cavities
Membrane
Pericardium
(around heart)
Pleura (around lungs)
Peritoneum (around
abdominopelvic cavity)
ALEXIS JADE V. BATICA | BSN-1 NH
Cavity
Pericardial cavity
Pleural cavity
Peritoneal cavity
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Pericardium and Pericardial Cavity
Pericardium
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Copyright © 2017 by McGraw-Hill Education. All rights
reserved. Printed in the United States of America.
Previous editions © 2014, 2011, and 2008. No part of this
publication may be reproduced or distributed in any form
or by any means, or stored in a database or retrieval
system, without the prior written consent of McGraw-Hill
Education.
visceral pericardium covers heart
parietal pericardium: thick, fibrous
pericardial cavity reduces friction
Peritoneum
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visceral peritoneum covers, anchors organs;
double layers called mesenteries
parietal peritoneum lines inner wall of
abdominopelvic cavity
peritoneal cavity reduces friction
Pleura
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visceral pleura covers lungs
parietal pleura lines inner wall of thorax
pleural cavity reduces friction, adheres lungs
to thoracic wall
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