YEAR 2
QUARTER 1
2019/2020
Animal Physiology
SUMMARY OF THE COURSE ANIMAL PHYSIOLOGY
NWI-BB005C
ELISE REUVEKAMP
,Content
Introduction............................................................................................................................................. 2
Osmosis and osmoregulation .................................................................................................................. 2
Excretion: basic processes in the kidney ................................................................................................. 7
Digestion................................................................................................................................................ 14
Energy physiology.................................................................................................................................. 20
, Introduction
Physiology: how does an animal function an how does the animal deals with the (changing)
environment
There are two principle types of relation between their internal and external environments
- Conformity → when the condition outside an animals body changes, the animal may permit
its internal environment to match the external conditions and thus change along with the
outside changes
- Regulation → The animal may maintain constancy in its internal environment
Individual animals subjected to a change in their external environment exhibit acute and chronic
responses to the environmental change
- Acute responses: responses exhibited during the first minutes or hours after an
environmental change
- Chronic response: a long standing changed to a prolonged exposure of new environmental
conditions. But can be reversed
- Evolutionary response: involving changes of the genotype, which is a response that cannot
be reversed.
Osmosis and osmoregulation
Key concepts:
- Water and ion exchange between a cell/organism and its environment mainly depends on
physicochemical processes and membrane properties.
➢ Diffusion and osmosis
➢ Water balance and ion regulation
- The tonic properties of a solution are always related to the permeability of a plasma
membrane
Osmoregulation (also known as hydromineral regulation) covers the process that regulate the water
and salt contents of bodily fluids.
- Osmolarity: the total concentration of osmotically active particles per litre of water is
expressed in Osmoles (Osmol)
- Osmolality: Osmoles per kg of water
Animals will need to regulate the water and salt contents, and osmotically problems are directly
related to the ion concentrations in and outside the cell/animal. We therefore speak of osmotic
gradients.
Diffusion and osmosis
Diffusion is the random movement of particles as a result of their thermal energy. The rate of
diffusion (J) of a particle can be calculated as follows: