Chapter 1: Basic Scientific Principles of Physiology
Introduction
● Anatomy - the study of structure
● Physiology - study of function
○ Structure us related to function because the structure determines the function which in turn determines how the body/organ
and so on is structured - 2 are interdependent
Levels of Organization
● The body is very complex and consists of many components - smallest
being a atom to the organism itself
● Levels - smallest to largest
○ Chemical level - the atoms, molecules, macromolecules that we are
made of
○ Cellular level - the smallest living units in our bodies
○ Tissue level - groups of cell specialized to perform specific
functions
○ Organ level - a structure consisting of many tissues specialized to
perform specific function
○ Organ system - system consisting of more than one organ
specialized to perform a range of functions
○ Organisms level - the whole individual
Characteristics of Life
● Essential for maintenance of life
○ Sensitivity - organisms need to be able to sense and respond to changes in their environment such as changes in light labels,
temperature, chemical composition, presence of threats, etc
○ Nutrition - seeking out, ingesting and using food to supply energy and the raw materials for growth and development
○ Respiration - organisms obtains and uses oxygen to release energy from food to power
○ Movement - the ability to change position is essential if an organism is to be able to escape threats, find food, other members
of species, etc
○ Growth - essential for the development of an organism from birth to adulthood but also for renewal and repair of body parts
during the life of an organism
○ Reproduction - essential process not for survival of the individual but for survival of the species. Sexual reproduction has been
added bonus of continually mixing and re-mixing genetic material to produce genetically unique individuals each time, which
increases the ability of a species to adapt and survive over the very long term
○ Excretion - removal of waste substances produced by metabolic processes from the body to prevent them from building up
Bodily Requirements
1. Water
a. Most abundant substances in the body
b. At birth around 78% of the body is made up of water
c. Reduces to 65% at age 1, 55-60% to adulthood
d. We evolved to operate in watery environments; cells are filled with watery salty solution in which our cellular processes are
carried out and these cells are bathed in a watery salty solution
e. Blood is mainly water, needed to transport substances around the body
f. Body water regulates body temperature since sweating is important mechanisms for evaporating cooling
2. Food: food supplies the energy and raw materials for organism to fulfil all the essential activities of life
3. Oxygen: required for the release of energy from food by the oxidation of high energy, food substances. Exists naturally in the air
4. Sunlight: all sunlight on earth depends on sunlight since plants need this to grow and other organisms depend directly or indirectly on
plants for foods
Life At the Chemical Level
The Elements
● All matter is made up a range of around 100 elements
● A chemical element is a pure chemical substance that cannot be broken down into anything simpler by chemical means
● More than 100 elements exist but only 98 exist naturally
The Smallest Unit of Matter: The Atom
● Atoms are building blocks of matter
● Atom consist of electrons., neutrons and protons
○ Protons and neutrons are at the center of a atom while electrons orbit around the nucleus
● Atom structures
○ Nucleus is alway central
○ # of proton is the atomic number
Introduction
● Anatomy - the study of structure
● Physiology - study of function
○ Structure us related to function because the structure determines the function which in turn determines how the body/organ
and so on is structured - 2 are interdependent
Levels of Organization
● The body is very complex and consists of many components - smallest
being a atom to the organism itself
● Levels - smallest to largest
○ Chemical level - the atoms, molecules, macromolecules that we are
made of
○ Cellular level - the smallest living units in our bodies
○ Tissue level - groups of cell specialized to perform specific
functions
○ Organ level - a structure consisting of many tissues specialized to
perform specific function
○ Organ system - system consisting of more than one organ
specialized to perform a range of functions
○ Organisms level - the whole individual
Characteristics of Life
● Essential for maintenance of life
○ Sensitivity - organisms need to be able to sense and respond to changes in their environment such as changes in light labels,
temperature, chemical composition, presence of threats, etc
○ Nutrition - seeking out, ingesting and using food to supply energy and the raw materials for growth and development
○ Respiration - organisms obtains and uses oxygen to release energy from food to power
○ Movement - the ability to change position is essential if an organism is to be able to escape threats, find food, other members
of species, etc
○ Growth - essential for the development of an organism from birth to adulthood but also for renewal and repair of body parts
during the life of an organism
○ Reproduction - essential process not for survival of the individual but for survival of the species. Sexual reproduction has been
added bonus of continually mixing and re-mixing genetic material to produce genetically unique individuals each time, which
increases the ability of a species to adapt and survive over the very long term
○ Excretion - removal of waste substances produced by metabolic processes from the body to prevent them from building up
Bodily Requirements
1. Water
a. Most abundant substances in the body
b. At birth around 78% of the body is made up of water
c. Reduces to 65% at age 1, 55-60% to adulthood
d. We evolved to operate in watery environments; cells are filled with watery salty solution in which our cellular processes are
carried out and these cells are bathed in a watery salty solution
e. Blood is mainly water, needed to transport substances around the body
f. Body water regulates body temperature since sweating is important mechanisms for evaporating cooling
2. Food: food supplies the energy and raw materials for organism to fulfil all the essential activities of life
3. Oxygen: required for the release of energy from food by the oxidation of high energy, food substances. Exists naturally in the air
4. Sunlight: all sunlight on earth depends on sunlight since plants need this to grow and other organisms depend directly or indirectly on
plants for foods
Life At the Chemical Level
The Elements
● All matter is made up a range of around 100 elements
● A chemical element is a pure chemical substance that cannot be broken down into anything simpler by chemical means
● More than 100 elements exist but only 98 exist naturally
The Smallest Unit of Matter: The Atom
● Atoms are building blocks of matter
● Atom consist of electrons., neutrons and protons
○ Protons and neutrons are at the center of a atom while electrons orbit around the nucleus
● Atom structures
○ Nucleus is alway central
○ # of proton is the atomic number
