Biological Molecules: Water Flashcards
Name the 4 different types of specimen sampling/ viewing
1) Dry mount
2) Wet mount
3) Squash slides
4) Smear slides
The 2 steps to dry mount
1) The specimen is viewed either whole or cut - Sectioning
2) Place a cover slip over the sample
The 2 steps to wet mount
1) Specimens are suspended in liquid
2) A cover slip is placenta an angle over the sample
The 3 steps to squash slides
1) A wet mount is prepared
3) A lense tissue is gently pressed down over the cover slip
4) Don’t break the cover slip
What precautions can be taken to prevent damage to a cover slip?
Squash the sample in-between two slides
The 3 steps to smear slides
1) The edge of a slide is used to wear the sample thinly and evenly
Hydrogen Bond
The electrostatic attraction between a slightly ___1____ hydrogen atom of one water molecule and the slightly ____2____ oxygen atom of another water molecule produces ____3____
1) Positive
2) Negative
3) Hydrogen bond
What does oxygen do with the shared electrons and why?
Drags the shared electrons closer to it because it has bigger nucleus. (A greedy git)
What bond is between the oxygen and hydrogen atoms?
Covalent
What bond is between each of the water molecules?
Electrostatic bond
A water molecule is a what?
Dipole
Dipole is where…
Electrons are pulled to the the oxygen, creating a slightly positively charged hydrogen end and a slightly negatively charged oxygen side.
What is the difference polar and non-polar molecules?
Polar molecules have an unbalanced charge so slightly positive or negative whereas non-polar molecules are equally charged.
Cohesion…
Where water molecules bond to each other.
Adhesion…
Is between a water molecule bonding with a different molecule.
When the adhesion is stronger than the cohesion bonds a ______ is formed.
Meniscus
What is formed by cohesion bonds in water?
Surface tension
How does surface tension help organisms to live?
Pond skaters us this to move across water to feed.
What is the importance of cohesion and adhesion?
It results in capillary action allowing liquids to move up the xylem.
What is meant by high specific heat capacity?
It is the measure of kinetic energy of water molecules. These are held together by strong hydrogen bonds thus a lot of energy is needed to break these bonds.
What is the importance of high specific heat capacity in the survival of organisms.
1) It creates a thermally stable environment. Rising temperatures reduces oxygen levels.
2) Provides a stable internal temperature inside organisms allowing enzymes to work.
What is the importance in high latent heat of evaporation in living organisms. (Heat needed for evaporation)
Water acts as a coolant when evaporating. It maintains a stable temperature inside the organism.
What are the properties of Ice and who does it contribute to the survival of organisms.
- Less dense than water.
- At temperatures below 4 degrees water molecules align themselves in a crystalline structure that is less dense.
- It insulates the water below reducing rate of heat loss.
- Creates a stable environment.
Water as a Solvent.
- Water is dipole acting as a solvent for the ionic molecules.
- Water molecules are attracted to the charged part of the solute. They surround it and separate them from the rest.
- Cytoplasm is over 70% water it allows molecules to move and react.
- Allows for transportation of molecules e.g. bloodstream or xylem.
