Lesson 1 - chapter 1 Flashcards
attempts to explain the specific characteristics and mechanisms of the human body that make it a living being
science of human physiology
It links the basic sciences with
medicine and integrates multiple functions of the cells, tissues, and organs into the functions of the living human being.
science of human physiology
The basic living unit of the body
Each organ is
an aggregate of many different ___ held together by intercellular supporting structures.
cell
red blood
cells, numbering about ___________ in each human being,
transport oxygen from the lungs to the tissues.
25 trillion
_______ additional cells of other types perform functions different from those of the red blood cell
75 trillion
The entire body, then, contains about
_____ cells
100 trillion
cell possesses basic characteristics:
For the cell to produce energy in the form of Adenosine triphosphate, oxygen reacts with simplest
structures of fat, carbohydrates, and proteins.
Cells also reproduce and regenerate on their own to
maintain the needed amount in the body.
These cells are suspended in the extracellular fluid (internal
environment), in which its constituents are controlled.
about ____ percent of the adult human body is fluid, mainly
a water solution of ions and other substances.
60%
most of the fluid is inside the cells
intracellular fluid
1/3 is in the spaces outside the cells and is called
extracellular fluid
in constant motion throughout the body.
transported rapidly in the circulating blood and then mixed between the blood and the tissue fluids by diffusion
through the capillary walls.
extracellular fluid
here, are the ions and nutrients
needed by the cells to maintain life.
Thus, all cells live in
essentially the same environment
extracellular fluid
the extracellular fluid is also called the
internal environment of the body, or the _________
a term introduced more than 150 years ago by the great 19th-century French physiologist ______________
milieu intérieur
Claude Bernard
(1813–1878).
Cells are capable of living and performing their special
functions as long as the proper concentrations of _________, ______, _______, _______, _______ and other constituents are available in this INTERNAL environment.
oxygen,
glucose,
different ions,
amino acids,
fatty substances
contains large amounts of sodium, chloride, and bicarbonate ions plus nutrients for
the cells, such as oxygen, glucose, fatty acids, and amino acids
extracellular fluid
It also contains carbon dioxide that is being transported from the cells to the lungs to be excreted, plus other cellular waste products that are being transported to the kidneys for excretion.
extracellular fluid
it contains large amounts of potassium, magnesium, and phosphate ions instead of the sodium and chloride ions found in the extracellular fluid
intracellular fluid
In 1929 the American physiologist_________ coined the term homeostasis
Walter Cannon (1871–1945)
the maintenance of nearly constant conditions in the internal environment
homeostasis
All tissues and organs essentially work
together to achieve a common goal, to maintain a relatively
constant environment
homeostasis
various ions, nutrients, waste products, and other
constituents of the body are normally regulated within a
_________, rather than at FIXED VALUES
range of values
Variations in blood hydrogen ion concentration are normally less than ________ per liter
(0.000000005 moles per liter).
5 nanomoles
few millimoles per liter
1 million times greater than hydrogen ion
blood sodium concentration
is often considered to be a state of disrupted
homeostasis
Disease
even in the presence of disease,
homeostatic mechanisms continue to operate and maintain vital functions through ________.
multiple compensations
the discipline of ___________ seeks to
explain how the various physiological processes are
altered in diseases or injury
pathophysiology
✓ Cells are not stagnant; they are ________ because they have to perform the
homeostasis to sustain stability and normality
dynamic living
units
Functional problems are often related to
________ problems
structural
2 STAGES OF BLOOD TRANSPORT:
1st stage: Movement of blood throughout the circulatory system
2nd stage: movement
of fluid between the blood capillaries
and the intercellular spaces between
the tissue cells.
All the blood in the
circulation traverses the entire circuit
an average of 1each minute when
the body is at rest and
as many as _____
times each minute when a person is
extremely active
6
The capillary walls
are permeable to most molecules in
the blood plasma, with the exception
of __________, which are too large
to pass through capillaries readily
plasma proteins
There is a continuous
exchange of substances between the cells and the interstitial fluid and
between the interstitial fluid and the _______.
blood
large amounts of fluid and its dissolved constituents that cannot readily pass through the capillaries _________
back and forth between the blood and the tissue spaces
diffuse
process of diffusion is caused
by ____ of the molecules in both the plasma and
the interstitial fluid.
kinetic motion
plasma ang IF continue being mixed thereby maintaining _______ of the EXF
homogeneity
provides oxygen for the body and
removes carbon dioxide.
Respiratory System
The blood picks up oxygen in ________ thus acquiring
the oxygen needed by cells.
alveoli
membrane between the alveoli and the lumen of the pulmonary capillaries
alveolar membrane
only 0.4 to 2.0 micrometers
thick, and oxygen rapidly diffuses by molecular motion
through this membrane into the blood.
alveolar membrane
digests foods and facilitates absorption of nutrients.
large portion of the blood pumped by the heart also passes through the walls of ______
Gastrointestinal Tract
Undigested material that enters
the gastrointestinal tract and some waste products of
metabolism are eliminated in the __________.
feces
It dissolves nutrients, including carbohydrates, fatty
acids, and amino acids, that are absorbed from
ingested food into the extracellular fluid of the blood
Gastrointestinal Tract
metabolizes nutrients changing chemical compositions of
absorbed substances to more useful forms.
Liver
also eliminates
certain waste products produced in the body and toxic
substances that are ingested.
detoxification or removal of many drugs and chemicals that are ingested.
Liver
includes the muscles and bones,
tendons, cartilages, and filaments. It is used to obtain food for nutrition and provides motility for protection.
Musculoskeletal System
also provides motility for
protection against adverse surroundings, without which
the entire body, along with its homeostatic mechanisms,
could be destroyed
musculoskeletal system
ORGANS for Removal of Metabolic End Products
Lungs
kidney
liver
help excrete carbon dioxide from the blood, releasing it to
the lung alveoli. breathing out carries carbon dioxide into the atmosphere
Lungs
is the most abundant of all the
metabolism products.
Carbon dioxide
help regulate blood volume and blood pressure
Kidneys
One of its main functions is to excrete waste products, slats, water, urea
and uric acid, and excess of ions to regulate the EXF composition
Kidneys
kidneys perform their function by first filtering large quantities of plasma through the __________ into the TUBULES
glomerular capillaries
kidney 2nd process: _______into the blood the substances needed by the body, such as glucose,
amino acids, appropriate amounts of water, and many of the ions
reabsorbing
end products of cellular metabolism
urea and uric acid
performs a distinct function in detoxification, the removal
of ingested drugs and chemicals.
The end waste products are
primarily eliminated in the feces
Liver
REGULATION OF BODY FUNCTIONS:
Nervous System
Hormone Systems
Nervous System is composed of three major parts:
sensory input
central nervous system (integrative portion)
motor output
directs the activity of the muscular system and controls function of many internal organs.
Nervous System
detect the state of the body and its
surroundings.
Sensory receptors
The central nervous system is composed :
brain
spinal cord.
can store
information, generate thoughts, create ambition, and
determine reactions that the body performs in response
to the sensations.
brain
Appropriate signals are then transmitted through the __________ of the nervous system to carry out one’s desires.
motor output portion
operates at a subconscious level
and controls many functions of the internal organs,
including the
- level of pumping activity by the heart,
-movements of the gastrointestinal tract, and
- secretion by
many of the body’s glands
autonomic system
Located in the body are 8 major
ENDOCRINE GLANDS and several organs and tissues that
secrete chemical substances called _______
hormones
controls many metabolic functions of cells, including growth, rate of metabolism, and activities associated with reproduction.
It is being secreted by the
endocrine glands.
Hormones System
increases the rates of most chemical
reactions in all cells, thus helping set the tempo of
bodily activity
Thyroid hormone
controls glucose metabolism
Insulin
control sodium and
potassium ions and protein metabolism
adrenocortical hormones
controls bone calcium and
phosphate.
parathyroid hormone
regulates many muscular and secretory activities of the body
nervous system
regulates many metabolic functions
hormonal system
PROTECTION OF THE BODY:
Immune system
integumentary system
consists of the
white blood cells, tissue cells derived from white blood
cells, the thymus, lymph nodes, and lymph vessels
that protect the body from pathogens such as bacteria, viruses,
parasites, and fungi.
immune system
immune system distinguishes its own cells from harmful foreign cells and substances; and destroys the
invader by _________
or by producing sensitized
lymphocytes or specialized proteins like antibodies
that destroy or neutralize the invader
phagocytosis
provides protection against injury
and foreign invaders.
Integumentary System
It includes hair, nails, glands, and other
structures. It covers , cushions , and protects the
deeper tissues and organs of the body and generally
provides a boundary between the body’s internal environment and the out- side world.
integumentary system
generally comprises about 12% to 15% of
body weight
skin
is also important for
temperature regulation and excretion of wastes, and it
provides a sensory interface between the body and
the external environment.
integumentary system
provides formation of new beings like
ourselves, hence it may sometimes not be considered a
homeostatic function, it helps maintain homeostasis holistically
Reproductive System
Producing new beings translates to generating new
bodies in which ______of additional cells can exist in
a well-regulated internal environment.
trillions
all body structures are organized to help
maintain the _______ & ___________
automaticity and continuity of life
control systems operate within the organs to control functions of the individual parts of the organs
others operate ______
others operate throughout the entire body to control the
INTERRELATIONS between the organs
Essential for homeostasis
operate in all cells to control IF and EF
control interactions among organs
control systems
example of control systems of respiratory system, operating in association with the nervous
system:
regulates the concentration of carbon dioxide in the extracellular fluid.
example of control systems of liver and pancreas
regulate the
concentration of glucose in the extracellular fluid, and
kidneys regulate concentrations of hydrogen, sodium,
potassium, phosphate, and other ions in the extracellular
fluid.
regulation of oxygen concentration in the tissues is vested principally in the chemical characteristics of hemoglobin
oxygen-buffering function of hemoglobin
is a
major end product of the oxidative reactions in cells.
Carbon dioxide
degree of effectiveness with which a control
system maintains constant conditions is determined by the gain of the
negative feedback
Any stimulus is counteracted by a response that is
going to cause negativity to the initial stimulus
negative feedback
anticipate changes
brain use this to control to cause the
required muscle contraptions.
Feed-forward control systems
Most control systems of the body act by ________,
which can best be explained by reviewing some of
the homeostatic control systems mentioned previously
negative feedback
brain corrects the feed-forward signal, it sends
to the muscle the next time the movement is
going to be required. This process is called
__________
adaptive control
which is in a sense more or less
a delayed negative feedback control
adaptive control
can sometimes cause vicious cycles and death, and
other times it can be useful.
Positive feedback
A system in our body that exhibits the positive feedback response to what we call ______________with
changes that amplify the perturbation and therefore
leads to INSTABILITY rather than stability.
perturbation
· Each functional structure, or organ, helps maintain a constant
_______
internal environment
As long as _________is maintained, the cells of the body
continue to live and function properly.
homeostasis
Each cell benefits from homeostasis and in turn, each cell
contributes its share toward maintenance of homeostasis.
RECIPROCAL INTERPLAY
that provides
continuous automaticity of the body until 1 or more functional systems lose their ability to contribute their share of function
reciprocal interplay
Extreme dysfunction leads to
death
