Chapter 3 WATER: Flashcards
What is biological medium? (Water is the biological medium on earth)
There are two major types of growth media. •Cell culture-specific cell types derived from plants of animals •Microbiology culture-growing microorganism (Bacteria and yeast)
Does all living organisms require water more than any other substance?
YES! Every Organism needs water the most
What is the percentage of water inside a cell?
Cells are made of 70%-95% of water. Most cells are surrounded by water
Water molecule
Polar molecule
What does polarity do?
Polarity allows water molecules to form hydrogen bonds with other water molecules
Four emergent properties
1-Cohesive behavior 2- ability to moderate temperature 3- expansion upon freezing 4- Versatility as a solvent
Hydrogen Bonds
They hold water molecules together (cohesion) Picture them all linked together like children linking arms close together.
Cohesion
Helps the transport of water against gravity in plants
Adhesion
Is an attraction between different substances Ex) between water and plant cell walls Ex) clinging on to things! And miniscule example gripping the walls of graduated cylinder
Surface tension
Is a measure of how hard it is to break the surface of a liquid High surface tension level= collective strength of hydrogen bonds (allows spider to walk on water)
Spider legs
Have coated hydrophobic substance
Water a____d heat from warmer air and r________s stored heat to cooler air.
Absorbed Releases
Water can absorb or release a large amount of heat…
with only a slight change in its own temperature (By absorbing or releasing heat, oceans moderate coastal climates.)
Kinetic energy
is the energy of motion
Heat
is a measure of the total amount of kinetic energy due to molecular motion (example ice cubes absorbs heat from warm liquid as the ice melts.)
Heat passes to object with a warmer temperature to an object with a
cooler temperature
Temperature
measures the intensity of heat due to the average kinetic energy of molecules
Specific Heat
of a substance is the amount of heat that must be absorbed or lost for 1 g of that substance to change its temperature by 1oC
Specific Heat unit
1 cal/g/Celsuis Metal has a LOW specific heat allowing it to heat & cool quickly (think of your frying pan!)
calorie (cal)
is the amount of heat required to raise the temperature of 1 g of water by 1°C
Water heats & cools slowly; its high specific heat is traced to hydrogen bonding
Heat is absorbed when hydrogen bonds break Heat is released when hydrogen bonds form
Evaporative Cooling
As H bonds break as liquid (sweat) evaporates, its remaining surface cools (the skin). Evaporative cooling of water helps stabilize temperatures in organisms and bodies of water
Evaporation
liquid to gas
Heat of vaporization
is the heat a liquid must absorb for 1 g to be converted to gas Water has a high heat of vaporization (an emergent property due to strength of hydrogen bonding)
