1. Essential knowledge 2.A.3:
Organisms must exchange matter with the environment to grow, reproduce and maintain organization.

2. Molecules and atoms from the environment are necessary to build new molecules.
Carbon is at the base of all life
Carbon-most versatile building block of molecules. Why?
- 4 valence electrons
Can form 4 single covalent bonds
Capable of forming double and triple covalent bonds
Can combine with atoms of many different elements

3. Carbon moves from the environment to organisms where it is used to build carbohydrates, proteins, lipids or nucleic acids.

4. Carbon moves from the environment to organisms where it is used to build carbohydrates, proteins, lipids or nucleic acids.

5. Nitrogen moves from the environment to organisms where it is used in building proteins and nucleic acids.

6. Nitrogen moves from the environment to organisms where it is used in building proteins and nucleic acids.
Nucleotides – monomers of
DNA and RNA

7. Phosphorus moves from the environment to organisms where it is used in nucleic acids and certain lipids.
Phospholipid
Phospates make up the backbone of DNA and RNA

8. Properties of Water
With a partner, write a few sentences about the properties of water that were observed in the weird water activities.
Compare and Contrast the following terms as they apply to the properties of water:
Cohesion
Adhesion
High specific heat capacity
Universal solvent supports reactions
Heat of vaporization
Heat of fusion
Water’s thermal conductivity

9. What makes water so weird?
Most properties of water emerge because water is polar and hydrogen bonds form between adjacent water molecules.

10. Cohesion and Adhesion Cohesion: Water is attracted to water
Adhesion: Water is attracted to other substances

11. Surface Tension
The cohesive forces between liquid molecules are responsible for the phenomenon known as surface tension.
The cohesive forces between molecules in a liquid are shared with all neighboring molecules. Those on the surface have no neighboring molecules above and, thus, exhibit stronger attractive forces upon their nearest neighbors on and below the surface.

12. High specific heat capacity
This is why it takes so long to boil water!!

13. Universal solvent supports reactions

14. Heat of vaporization

15. Heat of fusion
water has a high heat of fusion, or the heat you need to take out of water to get it to solidify (freeze).
What all this means is that water can hold a lot of heat energy before it changes temperatures and states (solid to liquid to gas).
This property of water is great if you are an organism that lives in the water. Why, you might ask? A high heat of fusion means that, even if the temperature of the air changes a lot, water will shelter you from those changes and provide a pretty stable environment.

16. Water’s thermal conductivity
Even though only the bottom of the pot is heated, the temperature of all the water will quickly rise.

17. Lastly …
Thanks Water!!
I did not know how neat you were!

18. Surface area-to-volume ratios affect a biological system’s ability to obtain necessary resources or eliminate waste products

19. Why can’t cells be extremely large?
As cells increase in volume, the relative surface area decreases and demand for material resources increases; more cellular structures are necessary to adequately exchange materials and energy with the environment.
These limitations restrict cell size.

20. Examples of tissues and cells that increases their surface are to maximize absorptions of nutrients and the elimination of waste.
Root hairs
Root hairs
Cells of the alveoli
Cells of the villi
Microvilli

21. What have we learned today about cells?
The surface area of the plasma membrane must be large enough to adequately exchange materials;
smaller cells have a more favorable surface area-to-volume ratio for exchange of materials with the environment