JMU BIO 140 Lab check point 2

Why is it important to post-rinse when pipetting volumes less than 20 microliters?

Small volumes may not get expelled completely due to surface tension.

True/False: Pipettors are most accurate in the middle to top end of their volume range.

true

How can contamination be prevented in the laboratory?

-using barrier pipette tips
-changing pipette tips between solutions
-keeping test tubes and pipette tip boxes closed

What unit is pipetteing done in?

microliter (uL)

How many liters are in a micro liter?

10^-6 L

How do you convert milliliters to microliters?

move decimal three times to the right

Define biodiversity

increases as more tips and branches are added to the tree of life

Define species richess

number of species found in an area

Define Shannon diversity

measure of biodiversity which accounts for species richness and evenness

Define species abundance

the total number of individuals of each species

What are the major threats to biodiversity?

-mass extinction event
-habitat destruction and degragation
-habitat framentation

Define fragmentation

the splitting of contiguous areas of natural habitats into small. isolated fragments

Why are transects used?

to control the size of a sample area

What are the three basic steps of a PCR reaction?

-denaturing
-annealing
-extension

What occurs during denaturing?

-tubes are heated to 94 degrees
-hydrogen bonds break and separate into two strands

What occurs during annealing?

-temperature is lowered to 55 degrees
-primers attach to the dna template

What occurs during extension?

-temperature is increased to 72 degrees
-synthesis of new DNA occurs

What are the necessary ingredients for a PCR to proceed?

-template DNA
-reverse primer
-forward primer
-DNA polymerase
-nucleotides

How many times does the PCR reaction repeat itself?

30 times

How many copies are produced of the original DNA?

1 billion

What is the point of PCR reactions?

to complete DNA replication

What is the point of gel electrophoresis?

-separate DNA fragments
-determine the size of the DNA fragments
-determine the presence of DNA fragments of a certain size

DNA possess what charge?

net negative

Why are the gels dyed with Gel Red?

they stain the double stranded DNA in our gel

Why are marker or ladders used?

makes it easier to determine sizes of unknowns using comparison techniques

Why do you run a negative control?

It enables you to tell if your PCR was contaminated by DNA that was not from your sample

Why do you run a positive control?

it allows you to know if your PCR ran correctly

Why do you use gel loading dye?

-increases density of your sample
-allows you to visually monitor your progress

The rate at which DNA migrates through the gel is determined by?

molecular size of the DNA

What are the major steps of DNA barcoding?

-collect DNA from organism
-extract DNA
-run PCR
-gel electrophoriphis
-sequence DNA
-analyzing DNA

What are the major steps in DNA subway?

- importing DNA
-view sequence
-trim sequence
-pair sequence
-build consensus
-find BLAST
-select data
-MUSCLE
-create tree

Where can DNA be found in the cell?

-nucleus
-mitochondria
-chloroplast

Approximately how many bp should a barcode sequence be?

500bp

What primer is used for plants?

RbcL

What primer is used for invertebrate animals?

CO1

What is the primer used for fungui?

ITS

Define intra-specific divergence

within a species of DNA

Define inter-specific divergence

between species withing a DNA

What makes a good scientific poster?

-serve as a backdrop for the presenter
-concise as possible
-contain enough information to stand alone without the presenter

What should you not include in a poster?

abstract

What is optional in the poster sections?

methods