Bio 1106 Exam 1

When we performed experiment in lab then we use 1 : ---------- for proteins 2. ----------------for Sugar 3: ----------------- for lipids

Biuret, Benedicts, SudanIV

Staining cells such that their color is different from the background enhances which quality of the cells?

Contrast

Sketch and label and shortly describe the results of your electrophoresis gel experiment. Hint: Results from virtual lab

DNA 1: TNF 2 DNA 2: TNF 1 DNA 3: TNF 1 TNF 2 *look at lab for picture

True/False. It is possible to make a perfectly precise measurement.

False

True/False. Median is the average of a data set when it is arranged from least to greatest.

False

A buffer

donates H+

Electrophoresis buffer is used to create the

electric field

While examining a cell under a microscope, you observe a nucleus, ribosomes, cytoplasm, and mitochondria. You are examining a _____ cell.

eukaryotic

Bright-field microscopes use a combination of

glass lenses and light to view a specimen

Identify the independent and dependent variables. (Lab 1)

independent: cornstarch and sand dependent: the number of pillbugs

Sudan IV is reagent to identify

lipids

Copy and complete the table below (table 3.1 from the lab exercise)

look in report

Why did we use ethyl bromide Dye in electrophoresis gels?

to see the separated samples under UV light

null hypothesis

null hypopthesis the hypothesis that there is no significant difference between specified populations, any observed difference being due to sampling or experimental error

We checked the PH of different solutions and the null hypothesis for this experiment can be

All solutions have the same PH

When trying to find the unknown agent what could be the different reagents?

1. Benedict is Reducing sugars for carbohydrates 2. Iodine for starch 3. Biuret for protein 4. Sudan for lipids

In this experiment of antacids 1: What is dependent variable and what is independent variable . 2: In all antacids different buffers are used . Do all these buffers used to neutralize same acid?

1. The dependent variable is the color change. The independent variable is going to be the acid. 2. Yes?

difference between theory & hypothesis

A hypothesis is an educated guess to explain something. A theory is backed up with experiments and results. theory: - has greater range of experimental support - is supported by evidence - has stood the test of time - can be used to make predictions - NOT a guess - cant be proved wrong - theories are synthesized as the result of multiple experiments over time that suggest the same result hypothesis: - educated guess - can be proved wrong - argument that can be tested to see if - it is true - constructed before any applicable research has been done

alternate hypothesis

A statement that is accepted if the sample data provide sufficient evidence that the null hypothesis is false

pH scale acids & bases

Acids: 0-7, more H+ Bases: 7-14, less H+

Data set 1 : 1 3 5 7 9 Data set 2: 1 3 5 7 14 True/False. In both sets of data mean and median is 5.

False

True/False. DNA fragments are positively charged and when placed into an electrophoresis gel will travel through an electrical field towards the respective pole.

False, DNA is negatively charged

Tue/False. Coarse focus should only be used with the 4X objective.

False, can be 4x and 10x

True/False. Test tube with distilled water will be consider positive control for experiment to identify unknown sample?

False, distilled water is negative control

True/False. Reducing sugar produce color with benedict Reagent but heat is not required for this reaction

False, heat IS required

True/False. A high standard deviation means that the data is less spread out.

False, high standard deviation means data is MORE spread out

True/False. Iodine solution is used to detect reducing sugar and its color turned purple to red , orange and green accordingly presence of sugars.

False, iodine is for starch

True/False. Zero degrees Celsius is the same as 100 degrees Fahrenheit.

False, it is 32 degrees

True/False. The most common measurement scale for volume is grams.

False, it is L and mL

True/False. PH is a measure of (Concentration of H+) acidity on a scale of 0 through 20.

False, it's 0-14

True/False. In an experiment of Antacids we use acid drops as an indicator.

False, we used bromothymyl blue

The portion of a slide that is visible through the eyepiece is called the

Field of View

Chemical agent used to detect the starch

Iodine solution

How will you make 50 ml of 0 .8% agrose gel solution for experiment?

M= V x Percent .8%/100 = .008 50 x .008 = .4 grams *always divide % by 100

The total magnification of an image is determined by ______ the magnification power of the ocular lens and the magnification power of the objective lens used.

Multiplying

What is the null hypothesis for this experiment? (Lab 1)

Pillbugs will not move toward the choice chamber containing cornstarch. There will be no effect.

True/False. Variance measure how far individuals or data points in the group are spread out, in the set of data from the mean.

True

Which of your hypotheses (null or alternate) were supported by your data? How did you determine this? (Lab 1)

The alternate hypothesis was supported by the data since the pillbugs did move toward the cornstarch, the cornstarch contained nutrients and the sand didnt.

independent variable

The experimental factor that is manipulated; the variable whose effect is being studied

What is the advantage of starting with the 4X objective before moving to the 10X and then the 40X objective?

The field of view is larger, and it is easier to focus

How do the coarse and fine focus knobs work on a brightfield microscope?

The focus knobs move the stage up and down?

dependent variable

The outcome factor; the variable that may change in response to manipulations of the independent variable

Write an alternate hypothesis for this experiment. (Lab 1)

The pillbugs will move to the chamber with cornstarch. There is an effect.

Protist are different from Fungi by: Select all that apply.

The protists are invisible to the naked eye

Based on the features that you described above and what you observed in your specimen, was your unknown sample a prokaryote or a eukaryote? If it was a eukaryote, was it a plant, animal or protist? Explain your answer.

The unknown sample was a eukaryote because it contains a nucleus. It is a protist because it is single-celled. There's only one of them that's seen in the microscope.

True/False. A cell is the smallest unit of life that can function independently and perform all the activities necessary for life.

True

True/False. Alternate hypothesis can be: Height is more in males than females.

True

True/False. Best antacid is one that resist the changes in PH longest.

True

True/False. Condenser critically, regulates the contrast in light microscope .

True

True/False. DNA fragments can be separated by size using an electrophoresis gel.

True

True/False. DNA fragments run easily in gel when we use Buffer instead of water.

True

True/False. In this experiment of antacids,water was negative control.

True

True/False. Median is mid value in the ordered data set.

True

True/False. Null hypothesis for reducing sugar experiment can be: All samples have reducing sugars

True

True/False. Purpose of Installing comb into gel is to create well or pockets in the gel where samples can be placed that are required for testing.

True

True/False. The Null hypothesis for this experiment can be: There will be no difference in heights of students. (Lab 2)

True

True/False. The more acidic the solution, the lower the pH, and the greater the concentration of hydrogen ions.

True

Amino acid can be detected in the food with the

biurets solution

What part of all cells encases the cytoplasm and forms a boundary between the cell interior and cell exterior?

cell membrane

What structure found in plant cells is an organelle for storing water and metabolites?

central vacuole

What structure is found in plant cells but not in animal cells?

chloroplast

A photograph of a magnified specimen that is taken through a microscope is called a(n)

micrograph

When the pH of the stomach becomes too low (too acidic) it can cause pain and damage the stomach lining and it can cause

stomach ulcer

What was the control setup in this experiment? (Lab 1)

the sand

What is the choice chamber in this experiment? (Lab 1)

the sand and corn starch