Elemental composition of plants

Question 1

What percentage of living cells ARE water?

Answer 1

80-90%

Question 2

What makes up the dry weight of Cells?

Answer 2

• H, C, N, and O make up 96 percent of the dry weight
• P, S make up 3 percent
• Ions (K, Mg, Ca) make up less than 1 percent

Question 3

Bonds strongest to weakest

Answer 3

Covalent>Ionic>Hydrogen>hydrophobic interactions

Question 4

Covalent bonds

Answer 4

*strongest
*Formed by sharing electrons between each other
*Can be polar (H2O, NH3) or nonpolar (O2, CH4, CO2)

Question 5

Ionic Bonds

Answer 5

*All polar molecules
*Cl takes electron density from Na. + charge attracts negative charge

Question 6

Hydrogen Bonds

Answer 6

Intramolecular interaction

Question 7

Nonpolar hydrophobic interactions

Answer 7

lipids

Question 8

What are the four molecules that make up cells

Answer 8

Carbohydrates, proteins, lipids, nucleic acids

Question 9

Carbohydrates

Answer 9

*

Question 10

Building blocks of carbohydrates

Answer 10

• sugars (C1H1O)?

Question 11

Characteristics/properties of carbohydrates

Answer 11

Polar

Question 12

Functions of carbohydrates

Answer 12

*Sucrose (carbon transport)
*Starch (Carbon/energy storage)
*Cellulose (cell walls)

Question 13

Lipids

Question 14

Building blocks of lipids

Answer 14

Fatty acids, glycerol (C,H,O)

Question 15

Properties/characteristics of lipids

Answer 15

Non-polar (Hydrophobic)

Question 16

Functions of lipids

Answer 16

*Oils (carbon/energy storage)
*Membrane lipids (compartmentalization)