General Lab Midterm Exam

Under which objective lens is the field view the smallest

100x

oil immersion objective

100x

Low power objective

10x

The ocular eyepiece lens magnifies the image

10x

If you have a microscope with a 5x ocular lens and a 40x objective lens, what is the total magnification of the image?

200x

high power objective

40x

Scanning power objective

4x

The lowest power of a compound microscope ( and some microscopes don't have this objective ) has a magnification of

4x

Which of the following biological samples can be viewed microscopically in a beginning lab type setting?

Algae, human body cell, plant cell, bacteria

Graph or make calculations(Stage 3)

Analysis

A(n) __________is a scientific test often carried out under controlled conditions.

Experiment

Carry out strategy chosen in hypothesis; collect measurements ( Stage 2)

Experiment

The formation of a dark-blue or black color after the addition of iodine indicates that a sample contains a lipid

False

The total magnification of an image is determined by multiplying the power of the objective lens only.

False

At high power, always use which adjustment knob to focus the image

Fine

Possible explanation (stage 1)

Hypothesis

Which of the following parts of a compound microscope is nearest the observers eye when using the microscope?

Ocular lens

Sharing results( stage 4)

Report

Ability to distinguish fine detail of an image

Resolution

Which of the following scientist first proposed the pH scale?

Sorensen

Some students consume large amounts of caffeinated drinks to help them stay alert when studying. You notice that many who engage in this practice seem to do poorly on exams. Suppose you want to investigate the relationship between caffeine consumption and exam performance. Which of the following statements would be an appropriate hypothesis?

Students who consume large amounts of caffeine while studying have lower exam scores than students that consume less caffeine while studying.

Polysaccharides are polymers composed of

Sugars

Engaging in the basic activities that make up the scientific method (being curious, asking questions and seeking answers) is a natural part of being a human.

True

Formulating a true hypothesis is far less important than coming up with a good strategy to test the hypothesis

True

In a controlled experiment, all variables are held constant except the one being tested.

True

The formation of a green color after heating with Benedict's reagent indicates that a sample contains reducing sugar.

True

The pH of a substance can be measured by using pH paper or pH meter

True

Proteins are polymers composed of

amino acids

Ability to distinguish an object from the background

contrast

Recorded observations are called

data

Before you begin a scientific experiment, you should

decide on a strategy for carrying out the experiment, state a hypothesis

When utilizing the scientific method, there are two type of variables. They are

dependent and independent

The term ______ refers to the chemical potential of hydrogen

pH

When graphing your data, it is important that you

place the independent variable on the X-axis.

The range of numbers on the pH scale would be

0-14

Which of the following are functions of lipids?

Membrane structure, storage of energy

Always begin examining microscope slides with which objective power?

low

Apparent increase in the image size

magnification

Which reagent is used to detect the presence of reducing sugar?

Benedicts

Which reagent is used to detect the presence of protein?

Biuret

Which color changes represent a positive reaction for the presence of protein using the Biuret test?

Blue to purple

Which color changes represent a positive reaction for the presence of starch using the iodine test?

Brown to blue/black

Which of the following parts of a compound microscope is shushed to regulate the amount of light coming through the specimen

Diaphragm

Imagine that you wish to compare two different diets that will be fed to tadpoles raised in a lab. One diet is meat-based fish food, and the other is the traditional diet of boiled lettuce. You want to see if the meat-based diet will be associated with an increase in the average weight of the tadpoles. In your experiment, you keep all other factors, such as tadpole density per pan, temperature, pH, and the amount of food the sarhe. The only difference between your control and experimental groups is the type of food the tadpoles receive. What is the independent variable for the tadpole diet experiment?

Diet

Which Reagan's is used to detect the presence of starch?

Iodine

Which question can you ask yourself to determine the dependent variable of an experiment?

Which will I measure in the experiment?

When graphing your data, place the dependent variable on the _____ axis.

Y

The negative control used in chemical composition of cells experiments was ___________

distilled water

Which molecule is hydrolyzed (digested) by amylase?

starch

An unknown sample is tested for chemical composition. You receive the following results. lodine test= black Biuret test= blue Benedict's test = green paper lipid test = greasy spot Which of the following are present in this sample?

starch, lipid, sugar

Which of the following are functions of carbohydrates

storage of energy, structural support

Which of the following are functions of proteins?

structural support, catalytic activity

A hypothesis must be

testable

In an experiment determining the effects of antibiotics on the treatment of pneumonia in mice, two groups of mice with pneumonia are compared. One group, group A, receives no antibiotic, and the other group, group B, receives 10 mg/kg of body weight of a new antibiotic. Besides the administration of the antibiotic, there are no differences between the two grodps of mice. What is the purpose of group A?

to ensure that only the treatment with antibiotics affects pneumonia

This is a temporary preparation useful in viewing living organisms or tissues

wet mount