Biology 1500 Lab Practical Review
100μL is equivalent to:
0.1ml
how to read a micropipette (unit conversions:
1,000µL=1ml 1,000,000µL=1L Typically used micropipettes: P 20 (1 μL - 20 μL), P 200 (20 μL - 200 μL), P 1000 (~100 μL - 1000 μL) P1000: 160uL Thousands: 0 Hundreds: 1 Tens: 6 P200: 16uL Hundreds: 0 Tens: 1 Ones: 6 P20: 1.6uL Tens: 0 Ones: 1 Tenths: 6
Steps of the Scientific Method
1. Ask a Question 2. Construct a Hypothesis 3. Test Your Hypothesis by Doing an Experiment 4. Analyze Your Data 5. Draw a Conclusion 6. repeat the experiment
What is the process of cellular respiration ? What are the steps? and how many ATP are generated during aerobic vs. anaerobic respiration and fermentation?
1. Cellular respiration is the process in which sugar is broken down to generate ATP. 2. Steps are glycolysis, pyruvate oxidation, the Krebs cycle, and oxidative phosphorylation. 3. In aerobic respiration yields 36-38 ATP while anaerobic yields 20-30 ATP
What factors determine how fast water moves across a membrane?
1. Hydrostatic pressure 2. Solute concentration difference
what happens to cells placed in hypertonic, isotonic and hypotonic solutions
1. In hypertonic the cell will shrivel 2. in isotonic it will stay the same 3. in hypotonic it will burst
If you were to attend lab in person, what is the proper attire you must wear before entering the lab?
1. Lab Coat 2. Long Pants 3. Mask 4. Closed Toed Shoes
Understand the light vs. dark reactions
1. Light reactions occur in the thylakoid and produce ATP and NADPH and release oxygen. 2. The dark reactions known as the Calvin cycle occur in the stroma and produce sugar.
What determines resolution?
1. Visual Acuity 2. Lens 3. Quality 4. Magnification 5. Lens Diameter
Ocular lenses found in most compound light microscopes have a magnification of..?
10x
Match the phase (or step) of photosynthesis to the process.
1st phase/step: Light Reactions 2nd phase/step: Dark Reactions
What is the optimal temperature for most enzymes?
20-40 degrees Celsius
You are using a compound microscope and you have the objective lens set to 40x. What is the total magnification you are using to view the specimen
400x
Law of independent assortment
A gene on one chromosome does not affect the segregation or inheritance of other chromosomes
What is the enzyme we will be using in lab today?
ALP
what does ALP do? and where it's found
ALP can be used to diagnose diseases like bone cancer, jaundice, and cirrhosis of the liver. It is found in the liver, bones, kidneys, and digestive system.
How to calculate Enzyme Activity?
Absorbance divided by time
If you get stuck while researching papers/topics or citing a paper what is the best solution?
Ask an NSU Librarian
Why are some species are unable to utilize oxygen as a final electron acceptor during cellular respiration?
Because of: 1. lack of oxygen in environment 2. lack of enzymes needed to inactivate toxic oxygen-based free radicals 3. lack if ETC proteins.
What color-producing chemical will be used in today's lab to determine the concentration of glucose solutions through absorbance readings?
Chromogen
What was used in place of NADP+ and why
DPIP was used because as it gets reduced it becomes colorless, allowing us to track the photosynthesis occurring.
What will happen in the experiment when light hits the chloroplasts?
DPIP will be reduced, it will change from blue to colorless, there will be an increase in light transmittance
What number do chromosomes of somatic cells contain?
Diploid number 2n
Name the two types of peas that we will be working with in the cellular respiration lab
Dormant peas and germinating peas
Understand the relationship between light wavelength and photosynthetic rate
Each photosystem has special pair of chlorophyll molecules, PSI and PSII. Plants grow better with blue or red light as opposed to green.
example of enzymes and substrate:
Enzyme: Alkaline phosphatase (ALP) and substrate para nitrophenol-phosphate (pNPP)
What are the products of fermentation?
Fermentation generates ATP and can produce ethanol, lactic acid, carbon dioxide, and hydrogen gas (H2).
Why are GMO's used?
GMOs are used to increase the yield of crops or to breed desired traits or protect against issues like pest.
At which stages of aerobic cellular respiration are ATP produced?
Glycolysis Chemiosmosis Kreb's Cycle
Match the process to its substrate (i.e. starting material).
Glycolysis: glucose Kreb's Cycle: pyruvic acid/pyruvate ETC: electrons
Homozygous
HH
Hetero
Hh
There is a(n) __________ relationship between the color of a solution and the wavelength of light it best absorbs
Inverse
Know the difference between a mono-, di-, and trihybrid cross
Mono: One trait crossed (HHxhh) Di-: two traits crossed (HHIIxhhii) Tri-: three traits crossed ( HHIIJJxhhiijj)
Understand how respiration occurs in eukaryotes and prokaryotes
Most eukaryotes use cellular respiration, aerobic, to make energy. Prokaryotes may use aerobic, anaerobic, or fermentation
What micropipette(s) could be used to measure out 175μL of liquid?
P1000 or P200
Know generation names (i.e., P1, F2, F3, F...)
P=parental, F1= first cross generation, F2= second cross generation
Match the photosystem to the specialized pigment molecules.
PSI: P700 PSII: P680
ALP catalyzes the hydrolysis of _______________ attached to proteins or lipids.
Phosphate groups
What macromolecule is an enzyme classified as?
Protein
What is the name of the machine we will use in today's lab to measure the amount of light that is absorbed by a solution?
Spectrophotometer
Parsimony:
States that the simplest explanation for how things work is usually best.
Similarity:
States that two experiments conducted in the exact same way will have the same results
Objectivity:
States that we should avoid letting our prior knowledge, prejudices, and biases influence how we collect and analyze data.
Flexibility:
States that we should be able to change our minds about long held ideas and theories once new data becomes available
During the dark reactions, atmospheric carbon dioxide (CO2) is brought into the leaf through tiny pores called: _________
Stomata
What happens to each component of the cellular respiration equation?
The equation shows that glucose is oxidized to carbon dioxide and oxygen is reduced to water, and energy is made. 6CO2 + 6H2O → C6H12O6 + 6O2.
What optima were found in the lab for temperature, pH, enzyme concentration of an enzyme?
The optima were at a neutral pH, high enzyme concentration, and temperature between 20-32 degrees Celsius.
Fermentation generates energy (i.e., ATP).
True
How does water move through diffusion?
Water moves from an area of low solute (high water) to high solute (little water)
how light spectra are reflected/absorbed and determine the color of an object
When sunlight is shined on a green leaf, the violet, red and orange wavelengths are absorbed. The reflected wavelengths appear green
Your resting heart rate is___________
When your heart rate is at its slowest; When your heart is pumping the least amount of blood
Sex chromosomes
XX or XY, determine sex and heritable genes
Compound Microscope:
allow for up to 1000x magnification, contains objectives and a fine focus knob, looks at subjects that cannot be seen by the naked eye
dissecting microscope
allow up to 100x magnification, lacks objective and fine knobs,used to look at larger subjects like a bug
Dependent Variable:
are determined by the independent variable.
Enzymes:
catalytic proteins that increase the rate of chemical reactions
What is used to compare observed ratios for a given cross compare with predicted ratios?
chi-square analysis
If you were given a sample of bacteria to analyze, which microscope would be best for quickly identifying the specimen?
compound
In prokaryotic cells, catabolism of pyruvate takes place in the __________________. Whereas, in eukaryotic cells, it occurs in the _________________________.
cytoplasm, mitochondria
Dominant allele
determines the organism's appearance
Osmosis:
diffusion of water
Which has a smaller wavelength: electrons or visible light?
electrons
A denatured enzyme can catalyze a chemical reaction.
false
Dissecting microscopes allow higher magnification than compound microscopes.
false
Enzyme activity typically occurs within a very broad pH range.
false
Plant cells are like red blood cells and can potentially burst when placed in solutions of varying tonicity
false
Simple diffusion requires energy input.
false
Who is known as the 'founder' of genetics?
gregor mendel
Recessive allele:
has no noticeable effect on appearance
Absorbance:
how much light is absorbed by the sample
Transmittance:
how much light went through the sample
independent variable
include things that cannot be controlled by the scientist.
Precision:
is a measure of the standard deviation away from the mean.
Alternative Hypothesis:
is a statement of what the scientist is trying to prove; "the treatment did have an effect".
Null hypothesis:
is a statement that the scientist is trying to disprove; "the treatment will have no effect".
Resolution:
is the ability of the microscope to resolve, or separate, two points.
Magnification:
is the ratio of the size of the image seen in the microscope versus the actual size of the objec
What does crenation mean and why does it occur?
is the shrinkage of cells that occurs when the surrounding solution is hypertonic to the cellular cytoplasm.
Autosomal
normal chromosomes
Tonicity is the measure of what?
osmotic pressure
What is the in vitrosubstrate for alkaline phosphatase (ALP) that we will be using in lab?
pNPP
When leaf pigments absorb light, electrons are boosted to a higher energy level, providing energy to:
produce ATP, reduce NADP+
TEM:
produce flat images, work by having a beam electron pass through the subject.
SEM:
produces a 3D image of the subject
The difference between dialysis tubing and real cell membranes is that
real membranes are more selective
Blue-colored objects absorb which wavelength of light the most?
red
Beer-lamberts law
shows the linear relationship between the concentration of a colored solution and its light absorbance.
Which of the following molecules can diffuse through a cell membrane?
small molecules
How to calculate total magnification?
take the power of the objective (4X, 10X, 40x) and multiply by the power of the eyepiece, usually 10X.
What happens if either the enzyme or substrate is limited?
the enzyme's reaction rate will remain constant
Accuracy:
the measure of the mean or average of several measurements.
Diffusion
the movement of a substance through a semi-permeable membrane.
Focal Plane:
the space you observe when using a microscope, can be limited
Law of segregation:
the two alleles for a heritable character separate (segregate) during gamete formation and end up in different gametes
how to find an Ideal Wavelength via maximal absorbance
the wavelength at which a colored solution will maximally absorb.
Moving molecules against their concentration gradient requires energy
true
When an enzyme's reaction rate doubles for every 10 degree Celsius increase in temperature it's called the Q10 effect.
true
Uniformity:
what we learn today will be true tomorrow, or that a certain experimental result today will cause the same result if we repeat the experiment tomorrow.
What color will the product of today's experiment (pNP) turn?
yellow