Textbook Notes (280,000)
CA (170,000)
UTSC (20,000)
Chapter 1

BIOB50H3 Chapter Notes - Chapter 1: Phenotypic Plasticity, Acclimatization, August Krogh

Biological Sciences
Course Code
Ted Petit

This preview shows pages 1-2. to view the full 6 pages of the document.
Chapter 1: Introduction to Physiological Principles:
Physiological process is a product of activities of complex tissues, organs and systems that arise
from genetic regulation of cells
Unifying themes in physiological process include:
o First: physiological processes obey physical and chemical laws
o Second: process are regulated to maintain internal conditions within acceptable ranges
Homeostasis (internal consistency): maintained through feedback loops that sense
conditions and tripper a response
o Third: physiological state of an animal is part of a phenotype: arise as a product of the
genetic makeup (genotype), and its interactions with the environment
o Fourth: the genotype: is a product of evolutionary changes in a group of organisms
(population or species)
Both genotype and the environment interact to product the phenotype.
The phenotype of an animal can influence its reproductive success
Physiological Past and Present:
Hippocrates: emphasized the importance of careful observation in the treatment of disease
Aristotle: emphasized on the relationship between structure and function
Claudius Galenus: founder of physiology. He designed experiments to probe function of the
Ibn al-Nafis: described the relationship between the lungs and the aeration of the blood
Jean Fernal: outlined the current state of knowledge of human health and disease
Andreas Vesalius: author of first modern anatomy book
William Harvey: identified paths of blood through the body, and showed the contraction of
the heart power this movement
Physiologist formed two categories: iatrochemists and iatrophysiscts:
o Iatrochemists: believed that the body function involved only chemical reactions
o Iatrophysicists: believed that only [hysical process were involved
Albert von Haller: proposed that bodily functions were combination of physical and chemical
Mathias Schielden and Theodor Schwaan: formed the cell theory
Claude Bernard: discovered myoglobin carries oxygen, liver contains glycogen, that nerves
can regulate blood flow and that ductless glands produce internal secretions
o Contributions: milieu interieur (internal environment): Organisms have a distinct
internal environment despite changes in the external environment
Per Scholander: influential comparative physiologists (dealt with diversity of physiological
C. Ladd Prosser: discovered central pattern generators
o Central Pattern generators: these groups of neurons coordinate many rhythmic
Knut Nielson: research on understanding on how animals live in harsh and unusual environment’s
George Bartholomew: founder of ecological physiology; study of how an organism interact with
the environment
Peter Hochacha and Somero: founder of the field of adaptational
Sub disciplines in Physiological Research

Only pages 1-2 are available for preview. Some parts have been intentionally blurred.

There are three main ways to categorize physiological subdisplines: biological level of
organization, by the nature of the process that cause physiological variation, and by the ultimate
goals of the researcher
Physiological sub disciplines can be distibguished by the biological level of organization:
Cell and molecular physiologists:
study the phenomenon that occurs at the cellular level (signal
transduction, metabolic biochemistry etc.)
System physiologist:
concerned with how cells and tissue interact to carry out specific
Organismal physiologist:
concerned with the way an intact animal undertakes a specific process
or response
Ecological physiologists:
how the physiological properties of an animal influence the disturbance
and abundances of a species or population
Integrative physiologist:
attempts to understand physiological processes at a variety of levels of
biological organizations and across multiply physiological systems
Reductionism: assumes that we can learn about a system by studying the function of its parts
o However many process have characteristics are not apparent just by examining the
components of the part
o Emergence: the whole is often more than the sum of its parts
These properties are due to interaction of the components of parts of the system
Physiological subdisplines can be distinguished by the process that generates
Developmental physiologist:
studies how structures and functions change as animals grow
through their life stages
Environmental physiologists:
assesses how animals mount physiological response to environmental
Evolutionary physiology:
is primarily concerned with explaining how specific physiological traits
arise within lineages over generations
o Animal physiology can be pure or an applied science:
Applied physiologist:
intended to achieve a specific, or practical goal (ultimate goal)
Medical physiology is to understand human disease, and model systems
Comparative physiologist:
studies animals to explore the origin’s and nature of physiological
BOX 1.1:
Model species is an organism that is used because it has features that are conducive to
experimentation, and understanding a process in the model provides insight into how the process
work in other species
August Krogh Principle: For every biological problem there is an organism on which it can be
most conveniently studied
Model is chosen because of: parallels with human biology, they have unusual anatomical features,
their developmental biology and the ease with which genes can be modified
Unifying Themes in Physiology: *chart in notes*
Physics and chemistry: The Basis of physiology:
You're Reading a Preview

Unlock to view full version