Lab 1: Introduction to Biology
Lab Safety, scientific inquiry, basic microscopy
In this lab students will be introduced to lab safety and will
become acquainted with proper lab technique. They will learn about the
proper use and handling of a compound light microscope and observe a
variety of cells.
Exercise 1: Identify the parts of the microscope
Students will learn how to use each part of the microscope and will
label a drawing to help them understand the location and function of
each. They will also learn how to calculate the total magnification.
Exercise 2: View prepared slides
Students will put their knowledge to use and observe and sketch the
contents different prepared slides at varying magnifications.
Exercise 3: Investigate pond water
Students will learn how to make a wet mount and view pond water under the microscope.
Exercise 4: Prepare a finger plate in nutrient agar medium for the next lab
Lab 2: Cell, Prokaryotic
Culturing bacteria, simple and gram staining, cell wall structures
In this lab students will learn how to use the oil immersion
objective. They will be introduced the microbial world and perform a
simple stain (methylene blue) of different bacterial species. They will
learn what it means for an objective lens to be parfocal, the term
incubate, and why we need to stain bacterial cells. Students will also
learn how to perform a Gram stain. They will learn and observe the
difference between gram negative and gram positive bacteria.
Exercise 1: Ubiquity of microorganisms
Students will examine their finger plate from Lab 1 that was
incubated for 3 days at 37ºC. They will count and describe the
observed colonies.
Exercise 2: Use of the oil immersion objective to view simple stain and Gram stains of microorganisms
Students will learn the general operating procedure for oil
immersion microscopy. They will prepare a heat fixed bacterial smear
and perform simple (direct) staining with methylene blue. Finally they
will prepare a gram stain. Students will learn cellular morphology and
arrangements.
Lab 3: Cells, Eukaryotes (Will be done same week as Lab 2)
Plant and animal cellular structures and function
In this lab students will learn to identify the function of
organelles in an animal and plant cell. They will make observations
between the differences between Prokaryotes and Eukaryotes.
Exercises: Prepare and observe a variety of Eukaryotic cells: Onion
epidermal cells, elodea, potato, human check cells, carrots, cork, ripe
tomato, and yeast cells. Observe prepared slides: amoeba proteus,
spirogyra, rhizopus, hydra, human blood smear, and paramecium.
Lab 4: Cellular organization
Limitations on cell size
In this lab students will learn how cells interact with the
environment and how the cell membrane helps moves food, oxygen, water
into and waste out of the cell. Students will learn how to calculate
surface area and the volume of the cell to investigate how the size of
a cell affects the diffusion of molecules across the membrane.
Exercise 1: Cell size: Surface to volume ratios
Students will use cell models in the form of agar blocks to learn
about the relationship between surface area, volume, and the effect of
cell size on the efficiency of diffusion evident by color change. They
will make a graph of cube dimension vs. surface to volume ratio to
determine the relationship.
Exercise 2: Estimating cell size: Calibrating the microscope to
compare human cheek, onion, human blood smear, dicot root, and
paramecium cells.
Students will estimate the diameter of the microscope field and
compare the size of different cells. They will apply what they learned
in the first exercise to determine which cell would be more efficient
at moving materials.
Lab 5: Cellular transport (Will be done same week as Lab 4)
Rates of osmosis and diffusion
In this lab students will observe diffusion and osmosis and set up
an experiment to test osmosis. Student will be introduced to the
scientific method and how scientists use a hypothesis when constructing
an experiment. They will define passive and active transport, osmosis,
hypertonic solution, isotonic solution, kinetic energy, and semi
permeable membranes.
Exercise 1: Observation of osmosis
Using a potato and varying concentrations of salt solutions students
will hypothesize what will happen to the potatoes in each solution.
Exercise 2: Demonstration of diffusion
Students will observe and record the movement of ink over time in
Petri dishes with different materials covering the bottom. They will
calculate the rate of diffusion.
Exercise 3: Are plastic bags selectively permeable?
Students will compare two different lunch bags to determine if they
are selectively permeable using a starch solution inside the bag and an
iodine solution outside the bag. They will observe color changes as
the starch interacts with the iodine. Students will hypothesize which
bag will be more permeable. They will determine which direction the
molecules traveled and why.
Lab 6: Cellular enzymatic reactions
Enzyme activity (catalase, protease, amylase, invertase)
Students will investigate either the variable of enzyme
concentration or temperature on the activity of the amylase enzyme.
They will learn the function of enzymes in biological systems, factors
that affect the rate of enzymatic activity, and enzyme kinetics. Most
importantly students will learn how to design their own experiment.
They will learn how to use a graph to report their data and will be
able to explain the differences in independent and dependent variables.
Exercise: Students will design their own experiment to test how
either temperature or concentration will change the reaction rate of
fungal alpha-amylase. Students will visualize the activity by using
starch (amylose) and adding Lugol’s iodine solution to measure amylase
activity. The instructor will review the experimental design before
the lab to make sure students have a sound experiment including a
hypothesis, controls, and tables or other means of collecting data.
Lab 7: Cellular metabolism
Cellular respiration
In this lab students will investigate the reactants and products of
cellular respiration and which organisms carry out cellular
respiration. They will determine the role of “breathing” in aerobic
cellular respiration, and why the level of CO2 production
varies with the level of activity. Students will learn how to use
titration as a method of determining quantity of a substance. They
will learn about glycolysis, Krebs cycle, electron transport chain,
aerobic and anaerobic respiration.
Exercise 1: Investigate the relationship between the amount of CO2 production and varying levels of muscular activity.
In partners students will perform different activities and measure production of CO2 using NaOH and Bromothymol Blue Solution. They will analyze the relationship between levels of activity and the amount of CO2 produced.
Exercise 2: Investigate the effect of sucrose concentration on the rate of cellular respiration in yeast
Students will design their own experiment to answer the question:
Does concentration of sucrose affect the rate of cellular respiration
in yeast? The instructor will review the experimental design before
class.
Lab 8: Plant physiology
Photosynthesis in elodea or cabomba plants
In this lab students will investigate the importance photosynthesis
and variables that affect the rate of photosynthesis. They will learn
the equation for photosynthesis and compare it to cellular respiration.
Exercise: Measure the affect of differing amounts of light and/or the affect of pH on photosynthesis.
Students will design their own experiments based on a basic procedure to test their hypothesis.
Lab 9: Cell replication
Mitosis
In this lab students learn about the different phases of mitosis.
Exercise: Observe each of the five phases of mitosis in the cells of an onion root tip.
Students will harvest the young tips, fix them, digest them in acid,
treat them with a reagent, which stains chromosomes, and view them
under a microscope. Students will then estimate the proportion of time
that cells in actively dividing tissues, such as the root tip, actually
spend in M-phase and cytokinesis.
Lab 12: Plant anatomy and physiology (To be combined with Labs 8 & 9 above in same week)
Flower and seed dissection
In this lab students will examine the structures of flowers and
seeds. Students will be able to identify and name the reproductive
structures of flowers, define pollination, and meiosis. In this lab
students will relate the structure of each part to its function.
Students will learn the differences between monocot and dicot and
angiosperm and gymnosperm.
Exercise 1: Observation and dissection of a flower
Students will take apart a large flower and describe and count each
structure. They will mount a sample of each structure to their lab
report.
Exercise 2: Observation and dissection of corn
Students will observe baby corn and a fertilized ear of corn.
Students will record each structure. They will dissect a corn embryo
and label each structure.
Exercise 3: Wet mount of pollen
Students will examine pollen from the flower from Exercise 1 and draw what they see.
Exercise 4: Examining a dicot seed
Students will dissect a navy bean seed that has been soaked
overnight. They will draw and identify structures and functions and
compare the seed to the monocot corn seed.
Exercise 5: Dissect a pinecone
Students will dissect a female pinecone to find a fertilized seed.
They will also examine a male pinecone and note the differences between
the two. They will compare and contrast angiosperms to gymnosperms.
Lab 10: Anatomy structure and function
Animal dissection, examining internal anatomy of a frog
In this lab students will examine the structure and function of the
external and internal organs of a frog. They will learn about the
different body systems: skeletal, digestive, muscular, lymphatic,
endocrine, nervous, cardiovascular, reproductive, and urinary.
Students will compare what they see on the frog to the organs of humans.
Lab 11: Anatomy structure and function
Animal dissection, examining the external anatomy of a grasshopper
In this lab students will examine the external anatomy of a
grasshopper. They will learn about the structure of the grasshopper and
relate each to structure to its function. Students also visit the
Museum of Life and Science’s insectarium and see how the different
structures found on the grasshopper are similar and different in other
insects.
Lab 13: Animal behavior
Pillbug response to environmental parameters
Students will learn about ethology, the study of animal behavior
both learned and innate, and the difference between taxis and kinesis
using Armadillidium vulgare (pillbugs).
Exercise: Student will design their own experiment to determine
which stimulus (light, temperature, moisture, or one of the student’s
choice) the pillbugs use to find a home and what type of movement they
use to get there (taxis or kinesis) using choice chambers. They will
need to determine sample size, appropriate duration, and replication.
They will design data tables and present their data in a graph. The
instructor will review their experimental design before the lab.
Lab 14: Genetics
Eukaryotic and prokaryote DNA extraction
In this lab students will learn about the structure and function of
DNA. They will review the differences between prokaryotes and
eukaryotes. They will learn the importance of the plasma membrane and
the nuclear envelope as well as importance of DNA extraction
Exercise 1: Extraction of DNA from a strawberry
Students will perform a step by step process to extract the DNA. As
they are performing the extraction they will be asked to reflect on the
steps to identify why they are doing each.
Exercise 2: Exaction of DNA from E. coli
Students will perform a step by step process to extract the DNA. As
they are performing the extraction they will be asked to reflect on the
steps to identify why they are doing each. At the end students compare
and contrast each exercise to note the similarities and differences.
Lab 15: Molecular biology
Restriction enzyme analysis
In this experiment, DNA from the bacteriophage lambda (48,502 base
pairs in length) will be cut with a variety of restriction enzymes and
the resulting restriction fragments will be separated using gel
electrophoresis. They will learn why restriction enzymes are important
and what they do. Students will learn how to use a micropipette.
Exercise 1: Learn how to use a micropipette
Exercise 2: Digest DNA with restriction endonucleases
Three samples of Lambda (phage) DNA are incubated at 37 degrees C, each with one of the 3 restriction endonuclease enzymes: BamHI, EcoRI, and HindIII. A fourth sample will be the negative control in that is will be incubated without any endonuclease as our control.
Exercise 3: Cast an agarose gel and practice loading a practice plastic gel
Exercise 4: Load gel with cut DNA
Exercise 5: Electrophoresis and analysis of gel
Lab 16: Molecular biology
Bacterial DNA transformation and genetics
Students will perform a bacterial transformation of the pGREEN plasmid into competent E. coli cells.
This will reinforce the concept of genotype and phenotype being
directly controlled by the genes which are made of DNA. Students will
learn what it means to make a cell competent, why and how scientists
would use plasmids and how to select for transformed cells using
selectable markers on the plasmids.
Exercise: Bacterial transformation of pGREEN into E. coli cells.
Students will observe their plates after a day of incubation and determine transformation efficiency.
Lab 17 and 18: Heredity and evolution
Human DNA analysis: DNA extraction and PCR
During these two labs (17 and 18) students will be synthesizing all
the techniques that they have learned in previous labs. Students will
learn about single nucleotide polymorphisms and why they are important.
In these experiments, a sample of human cells is obtained by saline
mouthwash. DNA is extracted by boiling with Chelex resin, which binds
contaminating metal ions. PCR is then used to amplify a short region of
the TAS2R38 gene involved in tasting a bitter chemical PTC. The amplified PCR product is digested with the restriction enzyme HaeIII,
whose recognition sequence includes a SNP in the gene that is
coorelated to not tasting. One allele is cut by the enzyme, and one is
not – producing a restriction fragment length polymorphism (RFLP) that
can be separated on an agarose gel. Each student scores his or her
genotype, predicts their tasting ability, and then tastes PTC paper.
Class results show how well PTC tasting actually conforms to classical
Mendelian inheritance, and illustrates the modern concept of
pharmacogenetics – where a SNP genotype is used to predict drug
response. During the waiting periods students will use bioinformatics
algorithms for a better understanding of the experiment.
Lab 19: Nanobiotechnology
Synthesis of silver nanoparticles and antimicrobial effects
In this lab students will test claims that colloidal silver has
anti-microbial effects. Many products on the market contain these
nanoparticles. There are claims that they inhibit growth of bacteria
reducing odors and spoilage. Students will learn about nanoparticles
and other applications.
Exercise: Students will make colloidal silver and soak filter
paper. They will place the paper on Petri dishes of bacteria then
observe the dish after one day to draw conclusions about the effect of
silver nanoparticles on bacteria.
Instructors:
Amanda Marvelle received her PhD in Genetics and
Molecular Biology from the University of North Carolina at Chapel Hill
in 2010. After graduating, Amanda became the Education Director at the
Contemporary Science Center in Durham, NC, teaching high school
students applied biology field studies and developing teaching modules
in collaboration with North Carolina biotechnology companies. Amanda
has experience teaching and mentoring students in the field of Biology
at both the K-12 and undergraduate college levels. She has presented
numerous papers and posters on genetics-related topics and has over ten
publications.
Alice Mei Lee has a bachelors degree in Biology and received her PhD in Microbiology from the North
Carolina State Univeristy in 2009. After graduating, Alice became an
Education Director at the Contemporary Science Center in Durham, NC
teaching field study classes and biology labs for homeschooled
students. During her studies, Alice also gained a great deal of
experience as a graduate teaching assistant in her designated field and
through her previous work as a high school science teacher in the
United States and Africa. She has presented numerous posters, is a
member of professional activities and society memberships, and has over
six publications.
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