Module 1
Define ‘physiology’
- Defn.: the study of function in living organisms
What does physiology do?
- Explores mechanisms by which organisms control their internal environment regardless of what
happens in the external environment
- Attempts to explain the physical and chemical factors responsible for both normal function and
disease
Define ‘homeostasis’
- Defn.: the maintenance of relatively stable conditions within the internal environment
(interstitial fluid and blood plasma surrounding cells i.e., inside the blood, the cells, and the
organs) regardless of what is happening in the external environment (the space and contents of
the digestive ft. lumen of digestive tract, respiratory ft. lungs, and urogenital tracts)
How is homeostasis maintained?
- Homeostasis is maintained using negative and positive feedback control mechanisms
o Controlled by the nervous system (brain, spinal cord, and nerves) and the endocrine
system (hormones)
Negative Feedback Control Positive Feedback Control
Systems Systems
Function(s) Maintaining body temperature Generation of action potential
in nerve cells
Maintaining body fluid volumes Surge of luteinizing hormone
that causes ovulation
Mechanism Controlled variable (final Controlled variable keeps the
product) shuts off its own effector on, stimulating its own
production by the effector production
,Negative feedback control systems
- E.g. body temperature — the set point is 37oC, but temperature can fluctuate
o Above set point
The control center (hypothalamus)
signals the effector(s) to generate
sweat
o Below set point
The control center signals the
effector(s) to generate shivering and
heat conserving mechanisms, by
decreasing blood flow to the skin
Controlled variable is generated heat
Control center stops the shivering
and returns blood flow to
extremities, once temperature
returns to its set point
List the levels of organization in the human body
- Body’s structural hierarchy:
o Atoms
o Molecule
o Macromolecules
o Cellular organelles (expressed in different quantities in differs cells)
o Cells
o Tissues (groups of cells that all have the same specialization)
o Organs (two or more types of tissues combined to form a complex, functional unit)
o Systems (several organs that cooperate for a common function e.g. maintain
homeostasis)
o Organism (formed when organ systems are grouped together)
Expectation
Physiology vs. anatomy vs. cell biology
- Physiology: study of function within and between tissue and organ system
- Anatomy: study of structure of bodily components
- Cell biology: study of cellular structure and system
Internal vs external part of our bodies
- Internal: inside the blood, cells, and organs e.g. intracellular fluid, interstitial fluid, blood
plasma
- External: space and contents of the digestive, respiratory, and urogenital tracts
, Module 2
Body fluid compartments
- The body is divided into two major fluid compartments
o Intracellular fluid compartment
o Extracellular fluid compartment
Interstitial fluid compartment
Fluid directly outside, bathing the cells
Plasma
Watery (92%) portion of the blood
Contains water, proteins, ions nutrients, gases, and waste product
Colloidal solution—contains suspended substances, plasma proteins
such as albumins, globulins, and fibrinogen, that do not settle out of
solution
Total body water and chemical composition of body fluids
Let ‘*’ represent relative distribution of total body water (TBW)
Note: there is a big difference in ion concentration between the inside and outside of the cell, and a
small difference in ion concentration between the plasma and interstitial fluid.
Intracellular fluid Plasma Interstitial fluid
TBW ****** * **
What accounts for differences in chemical comp. of intracellular and interstitial fluids and plasma?
- The cell membrane
o Selectively permeable
o Forms a physical barrier between the intracellular fluid and
extracellular fluid
Module 3
Basic Cell Organelle Expectation Function(s)
Golgi - Protein packaging
If you were to design a ‘Sports Drink’ for athletes, what would it include
- Produces (a)and why? vesicles and (b)
secretory
storage vesicles
- Isotonic sports drinks—contain the same salt/sugar concentrations as e.g. lysosomes
the body; quickly
Secretory vesicles - Transport proteins out of the cell
replace lost fluids and give a quick boost in carbohydrates
Free
- ribosomes
Hypertonic sports drinks—contain greater slat/sugar - concentrations
Manufacture proteins
than the body; used
- Fixed ribosomes—attached to the ER
post-workout to increase muscle glycogen stores
- Free ribosomes—float in the cytoplasm
- Hypotonic sports drinks—contain less salt/sugar concentrations than the body; used for
and form polyribosomes (groups of 10 to
athletes that require fluid intake without a boost in carbohydrates
20 ribosomes)
Define ‘physiology’
- Defn.: the study of function in living organisms
What does physiology do?
- Explores mechanisms by which organisms control their internal environment regardless of what
happens in the external environment
- Attempts to explain the physical and chemical factors responsible for both normal function and
disease
Define ‘homeostasis’
- Defn.: the maintenance of relatively stable conditions within the internal environment
(interstitial fluid and blood plasma surrounding cells i.e., inside the blood, the cells, and the
organs) regardless of what is happening in the external environment (the space and contents of
the digestive ft. lumen of digestive tract, respiratory ft. lungs, and urogenital tracts)
How is homeostasis maintained?
- Homeostasis is maintained using negative and positive feedback control mechanisms
o Controlled by the nervous system (brain, spinal cord, and nerves) and the endocrine
system (hormones)
Negative Feedback Control Positive Feedback Control
Systems Systems
Function(s) Maintaining body temperature Generation of action potential
in nerve cells
Maintaining body fluid volumes Surge of luteinizing hormone
that causes ovulation
Mechanism Controlled variable (final Controlled variable keeps the
product) shuts off its own effector on, stimulating its own
production by the effector production
,Negative feedback control systems
- E.g. body temperature — the set point is 37oC, but temperature can fluctuate
o Above set point
The control center (hypothalamus)
signals the effector(s) to generate
sweat
o Below set point
The control center signals the
effector(s) to generate shivering and
heat conserving mechanisms, by
decreasing blood flow to the skin
Controlled variable is generated heat
Control center stops the shivering
and returns blood flow to
extremities, once temperature
returns to its set point
List the levels of organization in the human body
- Body’s structural hierarchy:
o Atoms
o Molecule
o Macromolecules
o Cellular organelles (expressed in different quantities in differs cells)
o Cells
o Tissues (groups of cells that all have the same specialization)
o Organs (two or more types of tissues combined to form a complex, functional unit)
o Systems (several organs that cooperate for a common function e.g. maintain
homeostasis)
o Organism (formed when organ systems are grouped together)
Expectation
Physiology vs. anatomy vs. cell biology
- Physiology: study of function within and between tissue and organ system
- Anatomy: study of structure of bodily components
- Cell biology: study of cellular structure and system
Internal vs external part of our bodies
- Internal: inside the blood, cells, and organs e.g. intracellular fluid, interstitial fluid, blood
plasma
- External: space and contents of the digestive, respiratory, and urogenital tracts
, Module 2
Body fluid compartments
- The body is divided into two major fluid compartments
o Intracellular fluid compartment
o Extracellular fluid compartment
Interstitial fluid compartment
Fluid directly outside, bathing the cells
Plasma
Watery (92%) portion of the blood
Contains water, proteins, ions nutrients, gases, and waste product
Colloidal solution—contains suspended substances, plasma proteins
such as albumins, globulins, and fibrinogen, that do not settle out of
solution
Total body water and chemical composition of body fluids
Let ‘*’ represent relative distribution of total body water (TBW)
Note: there is a big difference in ion concentration between the inside and outside of the cell, and a
small difference in ion concentration between the plasma and interstitial fluid.
Intracellular fluid Plasma Interstitial fluid
TBW ****** * **
What accounts for differences in chemical comp. of intracellular and interstitial fluids and plasma?
- The cell membrane
o Selectively permeable
o Forms a physical barrier between the intracellular fluid and
extracellular fluid
Module 3
Basic Cell Organelle Expectation Function(s)
Golgi - Protein packaging
If you were to design a ‘Sports Drink’ for athletes, what would it include
- Produces (a)and why? vesicles and (b)
secretory
storage vesicles
- Isotonic sports drinks—contain the same salt/sugar concentrations as e.g. lysosomes
the body; quickly
Secretory vesicles - Transport proteins out of the cell
replace lost fluids and give a quick boost in carbohydrates
Free
- ribosomes
Hypertonic sports drinks—contain greater slat/sugar - concentrations
Manufacture proteins
than the body; used
- Fixed ribosomes—attached to the ER
post-workout to increase muscle glycogen stores
- Free ribosomes—float in the cytoplasm
- Hypotonic sports drinks—contain less salt/sugar concentrations than the body; used for
and form polyribosomes (groups of 10 to
athletes that require fluid intake without a boost in carbohydrates
20 ribosomes)
