Bio 123 Lab Exam 1

College of lake county Bio123 Principles of Biology lab exam 1 (labs 1-4)

pseudoscience

claims or beliefs that are portrayed as scientific fact but cannot be evaluated using the scientific method

hypothesis

a statement which explains your observation and answers your question. -Must be testable -Must be falsifiable

theory

is a hypothesis supported by a large amount of experimental evidence and widely accepted within the scientific community -Much broader in scope than a hypothesis

prediction

statements that describe what should happen if the hypothesis is supported -should be an "if" "then" statement

dependent variable

the variable that will change when the independent variable is altered; this is what the researcher will measure or observe during the experiment

independent variable

is the variable that is being altered or changed by the researcher; it is the variable being tested

standard variable

variables kept the same across all test groups so they don't affect the results

control group

a part of an experiment that does not change during the experiment (receives a baseline value of the independent variable)

positive control

is a solution that is known to contain the organic molecule for which the test is design for

negative control

is known to not contain the organic molecule you are testing for

experimental group

is/are subjected to a change in the independent variable

sample size

represents the number of individuals or samples being tested

replicates

is an experiment being repeated several times, to ensure the results are consistent

scientific method in order

1. observation

2. question

3. hypothesis

4. Prediction

5. experiment

6. conclusion

Observation

Using one of your five senses to study something and describe a fact

question

is often in the form of How, What, or Why and they must be well-defined and testable

hypothesis

a statement which explains your observation and answers your question. -Must be testable -Must be falsifiable

prediction

statements that describe what should happen if the hypothesis is supported -should be an "if" "then" statement

experiment

is to test the hypothesis, providing data that will either support or falsify it. Experiments also have three variables, independent, dependent and standardized.

conclusion

A statement made about the hypothesis which supports or disproves it based on the outcome of the experiment.

how is theory and hypothesis different?

hypothesis is a testable idea made before extensive research, theory is a hypothesis supported by a large amount of evidence

why is sample size important?

in order to draw conclusions that are significant, it is important that the sample size be large enough

why is the number of replicas important?

to ensure results are reliable and consistent

sample size

represents the number of individuals or samples being tested

calculate the total magnification for scanning power

40

(4×10=40)

calculate the total magnification for low power

100

(10×10=100)

calculate the total magnification for high power

400

(40×100=400)

Field of View Formula

FOV_Low x Total Magnification_Low =FOV_Scanning x Total Magnification_Scanning

which objective provides the greatest field of view

Scanning

which objective provides the smallest field of view

high power

1 millimeter is equal to how many Micrometers

1,000 Micrometers

what happens to resolution when you increase magnification on a microscope?

decreases

what happens to the field of view when you increase magnification on a microscope?

decreases

what happens to depth of field when you increase magnification on a microscope?

decreases

what happens to resolution when you decrease magnification on a microscope

increases

what happens to field of view when you decrease magnification on a microscope

increases

what happens to depth of field when you decrease magnification on a microscope

increases

prokaryote

a unicellular (single cell) organism that lacks a nucleus or any other membrane-bound organelle

Eukaryote

can be single celled or multicellular organism that contains nuclei and membrane-bound organelles

single-celled organisms

also called unicellular, consists of a single cell

multi-cellular organism

are composed of multiple cells that are unable to survive on their own

colonial organisms

are composed of cells that could survive on their own but function better as a group

filamentous

where the cells are attached to each other in a long row

endosymbiosis

where a larger cell engulfed a photosynthetic bacterium

cytoplasmic streaming

the movement of the fluid substance (cytoplasm) within a plant or animal cell. The motion transports nutrients, proteins, and organelles within cells.

Which cells have membrane bound organelles Prokaryotic or Eukaryotic cells?

Eukaryotic cells

Describe differences in size between Prokaryotic and Eukaryotic cells

prokaryotic cells range from 0.1 to 5.0 micrometers (μm) in diameter and are significantly smaller than eukaryotic cells, which usually have diameters ranging from 10 to 100 μm.

Provide examples of Prokaryotic cells

bacteria, e. coli

Provide examples of Eukaryotic cells

animals, fungi, plants, and protists

how to calculate the size of a cell

divide the number of cells that cross the diameter of the field of view into the diameter of the field of view

nucleus

the center of an atom, which contains the protons and neutrons (except in a hydrogen atom/no neutrons)

plasma membrane

thin, flexible boundary between a cell and its environment that allows nutrients into the cell and allows waste and other products to leave the cell.

mitochondria

They are organelles that act like a digestive system that takes in nutrients, breaks them down, and. creates energy for the cell.

chloroplast

a type of plastid (a saclike organelle with a double membrane) that serves as the site of photosynthesis

cell wall

A rigid layer of nonliving material that surrounds the cells of plants and some other organisms

amyloplasts

an organelle in some plant cells that stores starch.

plasmodesmata

membrane-lined passages that connect the cytoplasm of adjacent cells and allow small molecules to move freely between the two cells.

pseudopods

A false foot or temporary bulge of cytoplasm used for feeding and movement in some protozoans

cilia

The hairlike projections on the outside of cells that move in a wavelike manner

organic molecule

Any Molecules that contain Both carbon and hydrogen

covalent bonds

A bond formed between atoms where electrons are shared

polar bonds

Electrons are not equally shared due to electronegativity

non-polar bonds

electrons shared equally

monomers

the single units that make up polymers (macromolecules). Monomer means a single unit.

polymers

a long molecule consisting of many similar or identical building blocks linked by a dehydration reactions.

dehydration reaction

A chemical reaction in which two molecules covalently bond to each other with the removal of water.

hydrolysis reaction

A chemical reaction in which a compound is broken down into smaller molecules by reacting with water

triglyceride

long term energy storage molecules formed during condensation synthesis between 3 fatty acids and one molecule of glycerol.

protein

large molecules composed of one or more long chains of amino acids and are an essential part of all living. organisms

lipid

Organic compounds that are waxy or oily. Store energy, form biological membranes, and send chemical messages.

amino acids

the building blocks for proteins. A chain of amino acids make up the primary structure of a proteins.

peptide bonds

the bond used by amino acids in the primary sequence

denaturation

The change in a proteins shape and consequent loss of its function brought about by heat, agitation, acid/base, alcohol, heavy metals, or other agents.

DNA

-Double-stranded -Four bases- adenosine, thymine, guanine, cytosine

RNA

-Single-stranded -Four bases- adenosine, uracil, guanine, cytosine

Nucleotides

monomer of nucleic acids made up of a 5-carbon sugar, a phosphate group, and a nitrogenous base

importance of positive and negative controls

The negative control confirms there is no contamination in the reagents.

The positive control confirms that the reagents are working.

qualitative data

information that can't actually be measured. Descriptions, observations, and opinions

quantitative data

gathers data in numerical form which can be put into categories, or in rank order, or measured in units of measurement.

What does the Benedict’s reagent test identify?

reducing sugars

What does the Iodine test identify?

Starch

What does the Sudan IV test identify?

lipids

What does the Biuret test identify?

Proteins

What does the Dische Diphenylamine test identify?

DNA – specifically deoxyribose

What color will show a positive result for the Benedict’s Test?

Red, orange, yellow, green

What color will show a positive result for the Iodine Test?

Dark blue/black (might look purple)

What color will show a positive result for the Sudan IV Test?

bright red (if the powder dissolves)

What color will show a positive result for the Biuret Test?

Purple/pink

What color will show a positive result for the Dische Diphenylamine Test?

Blue

What color will show a negative result for the Benedict’s Test?

Blue

What color will show a negative result for the Iodine Test?

yellow-brown

What color will show a negative result for the Sudan IV Test?

clear (powder doesn’t dissolve/clumps)

What color will show a negative result for the Biuret Test?

blue

What color will show a negative result for the Dische Diphenylamine Test?

clear

What solution would represent a positive control for the Benedict’s Test?

reducing sugar solution

What solution would represent a positive control for the Iodine Test?

Starch solution

What solution would represent a positive control for the Sudan IV Test?

lipid solution

What solution would represent a positive control for the Biuret Test?

Protein solution

What solution would represent a positive control for the Dische Diphenylamine Test?

DNA solution

What solution would represent a negative control for all the tests?

Water