Bio Lab 2 Flashcards
1
FALSE
2
TRUE
The concentration of a solution is commonly listed as molarity
3
FALSE
The positive control is a known substance that is expected to be positive when the test reagent is added. It is used to be sure the test
solution is working properly
4
FALSE
5
FALSE
Since lipids are nonpolar, they dissolve in nonpolar solvents
6
TRUE
Phenolphthalein is used as a pH indicator because it turns red in basic conditions
7
FALSE
8
TRUE
Recall that the Fluid Mosaic Model uses a phospholipid bilayer as its foundation. In this bilayer, the polar phospholipid heads face out, and the nonpolar phospholipid tails avoid water by remaining in the interior of
the membrane. The membrane interior is nonpolar, so nonpolar molecules move across readily
9
FALSE
Water will flow from an area of high water potential to an area of low potential
10
[A, B]
Stock solutions only have to be diluted, not made from scratch each time they are required
11
[A, D]
12
[A, B]
Carbohydrates are the main ingredient in soda and candy
13
[D]
Steak is the only choice with the majority of its calories from protein
14
[C]
Butter is mainly saturated fat.
15
[B, C]
DNA exclusively can be detected using Dische diphenylamine and has thymine as a nitrogenous base.
Both DNA and RNA have cytosine as a
nitrogenous base. Ribose has an group at C2, while DNA has H in that position.
16
A, B, C, D
The speed at which diffusion occurs is influenced by the size, polarity, solubility, and especially by the concentration gradient of molecules
17
B, C
Dialysis tubing has pores of a certain size, consequently, the size of a molecule is a determining factor in whether the molecule will be able to pass through dialysis tubing. Larger molecules may be too large to diffuse
through the tubing. A great difference between the concentration of a substance outside of the dialysis tubing compared to its concentration
inside the dialysis tubing is known as a steep concentration gradient. The steeper the concentration gradient, the faster diffusion will occur
18
[A, B, D]
19
[A, B, C, E]
The fluid mosaic model of cell membrane structure has a phospholipid bilayer as a foundational layer. Phospholipids are
arranged with their heads pointing out and their tails facing each other in the interior of the membrane. Interspersed amongst these phospholipids are integral proteins, which go all the way through the bilayer. Peripheral proteins occur along the side of the membrane, but do not penetrate the phospholipid bilayer. Carbohydrates extend in chains from the outside of the cell
membrane
20
A, B, C, D
All of these would be possible if human tissue could maintain viability after freezing. All of these would be possible if human tissue could maintain viability after freezing
21
B
22
B
23
A
By definition, the number of grams per 100 ml refers directly to the percent of solute in that solution
24
E
There are always 12 items in a dozen
25
B
The number of molecules in a mole is
similar to the idea of a dozen. One dozen elephants indicates 12 individuals, and one dozen mice indicates 12 individuals. It does not matter that elephants are larger than mice; the concept relates the number of individuals only, which is 12 per dozen. One mole of a substance always indicates molecules. One mole of water weighs 18g, while one mole of glucose weighs 180g. One mole of water has the same number of molecules as does a mole of glucose, because the number of molecules per mole does not change. A mole indicates the number of individual molecules present, just as a dozen does
26
B
One atom of Mg weighs 24
One atom of S weighs 32
One atom of O weighs 16
Weight of = 24 + 32 + 4(16)
27
C
The molecular weight of is 120
g/mole. 120 g/mole (0.5 moles/L) = 60 g/L
