Introduction To Physiology Flashcards
What is physiology?
THE STUDY OF THE BIOLOGICAL
FUNCTIONS OF ORGANS AND THEIR
INTERRELATIONSHIPS
Studies interplay of factors that affect growth (connectedness of each aspect of the body)
Physiology
Physiological difference between plants and animals
Plants
1.Mostly producers
2. Unlimited scheme of growth
3. Non-motile and must rely on immediate nutrient sources
4. Use large amounts of 02
5. Conserve nitrogen
6. Transports fluids/food through vascular tissues
7.Grow throughout their entire lifetime
Animals
1. Consumer
2. Limited
3. Can move around
4. Give off CO2
5. Give off nitrogen as waste
6. Bloodstream
7. Reaches certain stage and growth more or less stops
A french physiologist who is known as the father of modern physiology
Claude Bernard (1813 - 1878)
He observed that the internal environment remains remarkably constant despite changing conditions in the external environment
Claude Bernard
An American physiologist who coined the term homeostasis to describe this STABLE INTERNAL ENVIRONMENT in 1932
Walter Canon
2 Themes of Physiology
- Integration
- Homeostasis
It is an international conference brought together physiologists and researchers from around the world to discuss the latest advancements and research in the field of physiology held in Glasgow, Scotland, from August 1 to 6, 1993
The XXXII (32nd) Congress of the International Union of Physiological Sciences (IUPS)
• XXXII (32nd) Congress of the International
Union of Physiological Sciences in
Glasgow, Scotland on August 1-6, 1993
• Research levels from whole body, to
organs, tissues, cells, organelles, and
genes
• At present, from gene to function
Integrative Physiology
It takes in oxygen and removes waste gases
Respiratory system
The cardiovascular system is responsible
for delivering the oxygen to all parts of
our bodies
The cardiovascular system is responsible for delivering the oxygen to all parts of
our bodies
Cardiovascular system
___ and ___ are distributed by the blood
Nutrients and oxygen
Metabolic wastes are
eliminated by the ___ and
___ systems
Urinary and respiratory system
Biological hierarchy
A. Molecule: Actin
B. Organelle: Myofibril
(found only in muscle
cells)
C. Cell and tissue:
Muscle cell within
muscle tissue
D. Organ: Flight
muscle of a moth
Four Tissue Types
- Connective tissue
- Muscle (contractile) tissue
- Nerve tissue
- Epithelial tissue
- Binds together or supports cells, other tissues/organs
- It provides structural and nutritional support, stores energy, and helps in tissue repair.
- Examples: Bone, blood, adipose (fat) tissue, cartilage, and tendons.
Connective tissue
- Contracts on stimulation
- Movement, posture and heat production
Muscle (Contractile) Tissue
- Conducts nerve impulses throughout the body
- Examples: Brain, spinal cord, and nerves. It consists of neurons (nerve cells) and supporting cells (neuroglia or glial cells).
Nerve tissue
-Covers all body surfaces; lines all cavities; forms glands
- Protective barrier against the environment
- Examples: Skin epithelium, lining of the gastrointestinal tract, and epithelial cells in the kidneys.
Epithelial tissue
Major Organ System
Urinary
Nervous
Digestive
Endocrine
Respiratory
Reproduction
Integumentary
Skeletal
Muscular
Circulatory
Lymphatic
Three definitions of homeostasis
- DYNAMIC EQUILIBRIUM
- INSPITE OF MULTIPLE
STIMULI - MAINTAINED BY
NEGATIVE FEEDBACK
Homeostasis is often described as ___ ___ because it involves continuous adjustments to maintain a stable internal environment despite external changes.
dynamic equilibrium
Homeostasis maintains stability in the internal environment even when faced with multiple external ___ or ___.
Stimuli or changes
Homeostasis is primarily regulated by ___ ___ mechanisms. In this mechanism, a change in a physiological condition triggers responses that counteract the initial change, bringing the system back to its set point.
negative feedback
The ability of the body to maintain relatively
stable internal conditions even though there is
continuous change in the outside world
Homeostasis
Basic components of homeostatic control system
Receptor -> control center -> Effector
Step by step homeostatic control mechanism
Stimulus:
Produces
change
in variable
-> Change
detected
by receptor -> Input:
Information
sent along
afferent
pathway to -> Output:
Information sent
along efferent pathway to -> Response of
effector feeds
back to influence
magnitude of
stimulus and
returns
variable to
homeostasis
Regulation of
homeostasis is accomplished through the ___ and ___ system
nervous and endocrine system
DETECTS CHANGES (STIMULI) IN THE BODY.
Receptor
DETERMINES A SET POINT FOR A NORMAL RANGE.
Control center
CAUSES THE RESPONSE
DETERMINED BY THE CONTROL CENTER.
Effector
- A regulatory mechanism in which a
change in a controlled variable
triggers a response that opposes
the change - decreases the intensity of the
stimulus or eliminates it
-causes the system to change in the
opposite direction from the stimulus
Negative feedback
Most homeostatic control mechanisms are ___ ___ mechanisms
negative feedback
Mechanism where the output shuts
off or somehow alleviates the original stimulus
• Example: Regulation of blood glucose
Negative feedback
mechanism that enhances
or exaggerates the original stimulus so that
activity is accelerated
Positive feedback
It is considered positive because it results in change occurring in the ___ direction as the ___ stimulus
Same
Original
Positive feedback mechanisms usually control ___ ___ such as blood
clotting or childbirth
infrequent events
Positive feedback usually does not maintain ___. It is characterized by being short in duration, and infrequent.
Homeostasis
In positive feedback
systems, the output
____ or
___ the
original stimulus
• Example: Regulation
of blood clotting
Enhances or exaggerates
Most diseases cause ___ ___ (chills,
fevers, elevated white blood counts etc)
homeostatic imbalances
___ reduces our ability to maintain homeostasis, particularly managing
heat stress
Aging
Occurs when a disturbance of homeostasis or the body’s normal
equilibrium is not corrected
Illness
a fluctuation in the ability to maintain equilibrium and a constant environment within the body. For example, if a person is having a homeostatic imbalance they may not sweat properly
Homeostatic imbalance
crucial for maintaining homeostasis, but they can be overwhelmed or malfunction in certain conditions, such as diabetes mellitus and clotting disorders.
Feedback mechanism
Brings together everything known about an animal’s function to create an integral picture of how an animal operates in its environment.
Integrative science
- Study the structure and functions of the various parts of animals and plants; how these parts work together to allow organisms to perform their normal behaviors and respond to their environment
Physiologist
Learn about the control and regulation of processes within groups of cells and how the combined activities of this cell groups affect the function of the animal
Design experiments
Three unifying themes of physiological processes
- Obey physical and chemical laws
- Regulated to maintain internal conditions and trigger an appropriate response
- Physiological state of an animal is part of its phenotype, which arises as the product of the genetic make-up, or genotype, and its interaction with its environment.
Subdisciplines of physiology
- Comparative physiology
- Environmental physiology
- Evolutionary physiology
- Developmental physiology
- Cell physiology
Species are compared in order to discern physiological and environmental patterns
Comparative physiology
Examines organisms in the context of the environments they inhabit
Environmental physiology
Techniques of evolutionary biology and systematics are used to understand the evolution of organisms from physiological viewpoint focusing on physiological markers rather than anatomic markers
Evolutionary physiology
How physiological processes unfold during the course of organism development from embryo through larva or fetus to adulthood
Developmental physiology
Vital information on the physiology of cells themselves, which can be used to understand the physiological responses of tissues organs and organ system
Cell physiology
Central themes in physiology
- Structure or function relationships
- Adaptation, Acclimatization, and Acclimation
- Homeostasis
- Feedback control system
- Conformity and Regulation
- Function is based on structure
- Form fits function at all the levels of life, from molecules to organisms
- Knowledge of a structure provides insight into
what it does and how its works
Structural/Function Relationships
structure-function relationship is clear in the ___ ___ in the shape of bird wing.
aerodynamic efficiency
It is how well an object moves through the air with the least amount of resistance. The more __ __ something is, the less air slows it down, which means it can move faster and use less energy
Aerodynamic efficiency
What is the relationship between structure and function in bird wings related to aerodynamic efficiency?
The structure of bird wings is designed for aerodynamic efficiency. They have a honeycombed internal structure that makes the bones light but strong, flight muscles controlled by neurons that coordinate movement, and ample mitochondria in cells to provide the energy needed for flight.
How does the internal structure of bird bones contribute to flight?
Bird bones have a honeycombed internal structure, making them light but strong, which reduces weight and allows for more efficient flight
What role do neurons play in bird flight?
Neurons in birds transmit signals between the wings and brain, controlling flight muscles and coordinating movement for efficient flight.
Why are mitochondria important in bird flight?
Mitochondria provides the energy needed to power flight by generating ATP, which fuels the bird’s muscles during flight.
What are the levels of biological organization?
- Organism level
- Organ system level
- Organ and Tissue levels
- Cellular level
- Macromolecular level
- Molecular level
What is the relationship between the Molecular level and the Atoms?
The Molecular level consists of molecules formed by atoms. Atoms are the smallest units of matter and form the basis for all levels of biological organization.
Physiology of an organism is very well matched to the environment it occupies, thereby ensuring its survival
Adaptation, Acclimatization, and
Acclimation
What is adaptation in the context of evolution?
Adaptation is the process of evolution through natural selection, leading to an organism whose physiology, anatomy, and behavior are matched to the demands of its environment.
Is adaptation generally reversible or irreversible?
irreversible
What makes a physiological process adaptive in a population?
A physiological process is considered adaptive if it is present at high frequency in the population because it results in a higher probability of survival and reproduction compared to alternative processes.
How are physiological and anatomic adaptations passed on?
Physiological and anatomic adaptations are genetically based, passed on from generation to generation through DNA, and constantly shaped and maintained by natural selection.
a physiological, biochemical, or anatomic change within an individual animal during its life that results from an animal’s chronic exposure in its native habitat to new, naturally occurring environmental condition
EX: animal in migrate to high altitude
Acclimatization
refers to the same process as
acclimatization when the changes are
induced experimentally in the laboratory or
in the wild by an investigator
•animal placed in hypobaric chamber
Acclimation
Are acclimatization and acclimation reversible?
Reversible
“Constancy of the internal
environment is the condition of
free life”
-Claude Bernard
milieu interieur
“extended notion of internal
consistency to the organization and
function of cells, tissues and organs”
Walter B. Cannon
The evolution of ___ and the ___ systems that maintain it were essential factors in
allowing animals to venture from relatively
“physiologically friendly” environments and invade habitats more hostile to life processes.
Homeostasis
Physiological system
antagonistic hormones that help maintain glucose homeostasis
Insulin and glucagon
What is hypoinsulinism and what condition does it lead to?
a condition that leads to diabetes mellitus.
has clusters of endocrine cells called
islets of Langerhans with alpha cells that
produce glucagon and beta cells that produce insulin
Pancreas
Pancreas has clusters of endocrine cells called
__ of ___ with alpha cells that
produce ___ and beta cells that produce
insulin
islets of Langerhans
alpha - glucagon
beta -
What factors contribute to the development of diabetes mellitus?
Hereditary factors and obesity
What happens to blood sugar levels in diabetes mellitus?
Blood sugar levels become high, leading to sugar being excreted in the urine.
What are the common symptoms of diabetes mellitus?
excessive urination and excessive thirst.
if diabetes mellitus becomes severe ___ substitutes for ___ as the major fuel source, leading to the production of acidic metabolites, which can cause a life-threatening lowering of blood pH.
fat
glucose
- autoimmune disorder
- usually appears in childhood
- treatment: insulin injections
Type I diabetes mellitus (insulin-dependent
diabetes)
- usually due to target cells having a decreased
- responsiveness to insulin
- usually occurs after age 40 – risk increases with age
accounts for over 90% of diabetes cases
Type II diabetes mellitus (non-insulin-dependent
diabetes)
is the ability of selected organisms to lose almost all water and enter a state of reversible ametabolism.
Anhydrobiosis
- regulatory processes that maintain
homeostasis in the cells and multicellular
organisms depend on ___
Feedback
return of information to a controller that regulates a controlled variable.
Feedback
How does feedback work in regulating physiological variables?
Feedback occurs when sensory information about a particular variable (e.g., temperature, pH, salinity) is used to control processes in the cells, tissues, and organs that influence the internal level of that variable.
when an organism is confronted with changes
in its environment (e.g. changes in oxygen availability or salinity), it can respond in one or
two ways:
Conformity and Regulation
organisms that maintain their internal osmotic pressure by conforming to the osmotic pressure of their surrounding environment. This means that the concentration of solutes (such as salts) inside their bodies is similar to the concentration of solutes in the external environment, which allows them to avoid significant water loss or gain
Osmoconformers
environmental challenges induce
internal body changes that simply parallel the external conditions (unable to maintain
homeostasis)
e.g.
osmoconformers (starfish, shark)
Conformers
- organisms whose rate of oxygen consumption changes directly in response to the oxygen levels in their environment.
- do not actively regulate their oxygen uptake instead, their metabolic rate decreases as the availability of oxygen decreases
Oxyconformers
maintain a stable rate of oxygen consumption regardless of external oxygen levels
oxregulators
biochemical, physiological, behavioral,
and other mechanisms to regulate their internal environment over a broad range of external environmental changes (maintain homeostasis)
Regulators
biochemical, physiological, behavioral,
and other mechanisms to regulate their internal environment over a broad range of external environmental changes (maintain homeostasis)
Regulators
maintain ion concentrations of
body fluids above environmental levels when placed in dilute water vice
vers
Osmoregulators
is based largely on controlled
movement of solutes between internal fluids and the external environment
Osmoregulation
