Physiology of the Cell Flashcards
What is the approximate percentage of the body that is water?
60%
What are the sources of body water in animals?
Food and water.
What are the sources of water loss in animals?
Urination, defecation, respiration, evaporation & vocalization.
What is the name of the state when an animal has too little water?
Dehydration.
What is the name of the state when an animal has too much water?
Water intoxication.
What are the names of the compartments in which water resides in the body?
Intracellular, extracellular which consists of interstitial fluid, plasma & lymph.
Name 2 ways that abnormal fluid loss happens in animals.
Vomiting, diarrhea, blood loss, decreased intake of food or water.
Describe the path of intravenous fluids after they have been administered.
Plasma to interstitial fluid to intracellular fluid to lymph.
What is the body’s solvent.
Water
Why are electrolytes so named?
They are capable of conducting an electrical charge.
What 2 ions control the pH of body fluid?
The Hydroxyl and the Hydrogen ion.
True or False. The common solutes in the body are all equally distributed in the intracellular & extracellular spaces?
False. Different solutes are distributed in different proportions in the different spaces.
Maintenance of the osmolality of body fluid within the desired range is an example of what state?
Homeostasis.
How would you describe 2 fluids with equal osmolality?
Isotonic.
What direction will water flow in a situation where a cell is suspended in a fluid that is hypotonic to the contents of the cell?
Water will flow into the cell.
Compared to that of a normally hydrated patient how is the osmolality of the plasma of a dehydrated patient?
The plasma will have higher osmolality in the dehydrated patient.
What creates oncotic pressure?
Oncotic pressure is the osmotic pressure created by proteins as compared to dissolved substances.
What is the name of the protein that creates oncotic forces?
Albumin.
True or False. Water moves or doesn’t move between body compartments because channels in the barriers (membranes) between those compartments open and shut in response to signals from the body.
False. Water can move freely through membranes . Its “destination” is controlled by osmotic and oncotic forces.
True or False Osmotic pressure is never sufficient to over come gravity?
False.
What other force in the body is capable of moving fluid in the body and what generates this force?
Hydrostatic pressure. It is generated by the beating of the heart.
Give 2 examples of transport of solutes across a cellular membrane that don’t require energy.
Diffusion & Facilitated diffusion
Define diffusion. What obstacles are there to diffusion in the body?
Diffusion is the tendency of to spread out to be evenly distributed in the space available to them. Cell membranes and blood vessel epithelium are obstacles to this process.
True or False. The movement of solutes by facilitated diffusion requires energy.
False
List the 2 factors that affect the rate at which facilitated diffusion of a solute happens.
The concentration of the solute and the number of carrier proteins in the membrane available.
What is the defining factor of active membrane transport.
It requires energy to get solutes across cell membranes.
