Lab Four: Experiment 1
1. At what magnification do you first notice the ragweed pollen? I first noticed it when the magnification is at about 30
2. Which is bigger, rhinovirus or E. Coli? E. Coli is bigger
3. Based on the magnification, how many of the E. Coli can fit into the same space as the head of a pin? 10,000 E. Coli
4. About how many red blood cells could fit across the diameter of a human hair. (Again, look at the magnification scale)? About 100 blood cells
Lab Five: Experiment 1
Substance pH Guess pH Paper
Vinegar
3
5
Sodium bicarbonate
12
8
Milk
7
6
Root beer
2
5
Lemon Juice
1
5
Water
7
7
1. Compare and contrast acids and bases in terms of their H+ ion and OH- ion concentrations. Acids have higher concentrations of H+ and bases have higher concentrations of OH-. Solutions that are neutral have equal concentrations of OH- and H+.
2. Name two acids and two bases you used. Bases: Sodium bicarbonate and water. Acids: Milk and lemon juice.
Lab Five: Experiment 2
Cube dimensions
Surface area (cm2)
Volume (cm3)
Surface area: Volume
Distance of diffusion
1cmx1cmx1cm
6
1
6:1
3 mm
2cmx2cmx2cm
24
8
3:1
4 mm
1cmx1cmx6cm
36
6
6:1
3 ½ mm
1. How did the surface area affect the diffusion of the cube? What about the volume? What about the surface area to volume ration? Which of these had the greatest affect on the diffusion of the cube? The more volume the cube has along with the smaller ratio the more diffusion it’s going to have.
2. How does this experiment demonstrate the need for larger cells to divide? As a cell gets bigger, the outside is unable to keep up with the inside, because the inside grows a faster rate than the outside.
3. For the three cubes shown below determine their surface area, volume, and surface area to volume ratio. Then circle the one you believe would be the most efficient and write a summary stating why. Cube 1.5 x 1.5