BIOL 171L Midterm
According to the scientific method, why are we looking at more than one field of view under the microscope when collecting our data?
Because you want accurate data, less chance of error.
Complete the missing steps in the scientific method. 1. 2. Formulate a hypothesis 3. 4. 5. Analyze data 6. Evaluate hypothesis in light of results 7. Modify hypothesis to carry out new experiments 8.
1. Observe nature 2. Formulate a hypothesis 3. Make predictions on hypothesis 4. Experiment w/controls to test hypothesis 5. Analyze data 6. Evaluate hypothesis in light of results 7. Modify hypothesis to carry out new experiments 8. Share results w/other scientist so consensus can be reached
In your own words, define a cell.
A cell is a membrane bound substance that replicates itself.
What is a negative control?
A negative control is to show that a substance is absent. We need a negative control as part of the procedure to show what it means for a substance is not present from when it is present. Water is the negative control.
Name at least two of the four kingdoms that contain cells with a nucleus.
Anamilia and Plante
Name the biological emulsifier made in your liver.
Bile
Name one similarity and one difference between prokaryotic and eukaryotic cells.
Both have plasma membranes. Difference - prokaryotic do not have nucleus and eukaryotic have nucleus
What color did the lens paper stain?
Brown (negative)
What are the four principle types of organic matter found in the dry weight of cells?
Carbohydrates, lipids, nucleic acid, and proteins.
What carbohydrate is found in lens paper?
Cellulose
Name the cells that support the celery ridge.
Collenchyma
For each of the following cell types, provide one identifying characteristic: Collenchyma Sclerenchyma Parenchyma
Collenchyma - elongated Sclerenchyma - ridgid Parenchyma - isodiametric
What differences do you see in the starch content of corn seeds and pea seeds?
Corn - localize Pea - all over
Name the negative control in the sugar test (experiment 2)?
Distilled water
What is a solvent?
Does the dissolving
Name the term that defines cells with a nucleus.
Eukaryote
Where is starch localized in a potato cell?
Granules
Starch turns blue-black in the presence of _____________.
Iodine
A cell is sitting in a solution that has the same solute concentration as inside the cell. Name the type of solution.
Isotonic
Define diffusion.
Movement of molecules from high concentration to low concentration.
Name the instrument that measures osmotic potential.
Osomometer
Which cell type appeared first?
Prokaryotic
A test that determines the presence or absence of a test substance is called a ___________________ test.
Qualitative
Where is starch stored in plants?
Roots
Name the positive control in the starch test (experiment 2)?
Starch solution
Name the purpose of a starch.
Stored energy
What is a solute?
Substance that can be dissolved in water.
What is the purpose of stomata on a leaf surface?
The purpose of stomata on a leaf surface is to allow gas exchange in the interior of the leaf and to allow water vapor to escape the leaf.
What substance is Benedict's solution used to test for? What does it mean if the solution turns yellow-green color?
The substance we are testing for is reducing sugars. If the solution turns a yellow-green color there is a low-concentration of a substance present.
True or False. A qualitative test is to see if a substance is present or not.
True
True or False. A quantitative test is to see how much of a substance is present.
True
In addition to testing only one variable at a time, what are two other things that all well-designed experiments must include?
Use controls and have experiments be replicated.
Name the tissue that contains xylem cells.
Vascular
Does the iodine test distinguish between starch and cellulose?
Yes; lens paper was negative for starch but contains glucose.
Name the tissue that contains collenchyma cells.
ground (bulk)
The movement of water across a membrane is called _____________.
osmosis