LABS 1+2: SAFETY AND MACROMOLECULES
Heart - pathological waste
You want to test the effects of caffeine on blood pressure and heart rate. You divide forty subjects into four groups of ten, each group is given a different dose from pills containing either 750mg, 500mg, 250mg, or 0mg (placebo) of caffeine. You measure each subjects heart rate (bpm) and blood pressure (mmHg) three times every 30 minutes for 4 hours. What are the independent and dependent variables in this experiment?
Independent – caffeine dose (mg)
Dependent – heart rate (bpm) and blood pressure (mmHg)
Flasks X, Y, and Z contain solutions with different concentrations of the solute NaCl:
– Flask X has 0.5% NaCl
– Flask Y has 0.9% NaCl
– Flask Z has 1.5% NaCl
Red blood cells will be placed into each flask. Predict what will happen to the blood cells in each of the flasks.
Complete the Watson-Crick base pairing for the following sequence.
ATTTCCGA
When testing the patellar reflex, what two types of neurons are involved and which receives the initial stimulus? Which type of neuron is not involved in this pathway and why is it not needed?
Sensory (receives initial stimulus) and Motor neurons are involved Inter-neurons are not involved because this is a monosynaptic reflex – only one synapse is formed (between two neurons).
In order to break sucrose down into glucose and fructose, what process would you use?
You invented a new environmentally friendly pesticide to keep beetles from invading your vegetable garden. You want to run an experiment to make sure that your new pesticide is effective. State what you would use for a positive and negative control.
Positive control – expose plant to a pesticide known to be effective
Negative control – expose plant to no pesiticide
Left paper shows fall leaf, right shows spring. Chlorophyll a and b have been degraded in the fall leaf, lines are absent.
You decide to make some homemade wine, so you add yeast, water, sugar, and crushed grapes into a large bucket, but you don't have a lid for it, so you close it in a large dark closet. Explain why or why not fermentation will occur to produce the wine.
Not an anaerobic environment, no fermentation
The very outer layer that encases the heart is called the _______. Bordering that, there are three layers from outermost to innermost called _______, ________, ________.
The very outer layer that encases the heart is called the pericardium. Bordering that, there are three layers from outermost to innermost called epicardium, myocardium, endocardium.
You are diluting your stock solution of starch, which is 20 mg/ml. Your experiment requires a 16 ml of 3.2 mg/ml starch solution. How much of the stock solution and how much water do you need to mix together to make this solution?
C1V1 = C2V2
(20 mg/ml)(V1) = (3.2 mg/ml)(16 ml)
V1 = 2.56 ml stock solution
Add 13.44 ml water
The restriction enzyme, SalI, cuts at the following sites on the plasmid pIJ702. (See Board). How many bands would be produced on a gel electrophoresis containing this plasmid and restriction enzyme?
What happens to red blood cells in a hypotonic solution? Why? Would a plant cell react in the same way?
RBCs swell and burst because water rushes into the cell. No, the plant cell would get swollen but it won’t burst – the cell wall prevents it from bursting.
How would you prepare a 50 ml 2% gel if you had 1x TBE buffer and agarose? Give the weight and volume of the reagents.
1 g of agarose plus 50 ml 1x TBE buffer
2% = 0.02 so 50 x 0.02 = 1 g
You are testing Bob’s and Susan’s bloods to see if their blood types are compatible. (See Board)
SUSAN: AB+
BOB CAN DONATE TO SUSAN
Spectrophotometer
The restriction enzyme, SalI, cuts at the following sites on the plasmid pIJ702. (See Board). List the band sizes in order of those you expect to travel the farthest to those that you expect to travel the shortest distance on the gel.
300, 900, 2050, 2400
Phenol red immersion – make solution acidic indicated by yellow color by adding CO2. If plants are photosynthesizing solution will become red as they use the CO2 and produce O2, and bubbles will be formed.
Floating Disk Technique – use syringe to remove all gas from leaves until they sink. Place them into a beaker of liquid, if they begin to float this is a sign of photosynthesis due to creating of O2 bubbles.
Other accepted answers: Lugol’s or Benedict’s test for plant production of starch or glucose
One of your friends stole your candy. Luckily you are a scientist and were able to lift some DNA from the crime scene and obtain a sample of DNA from each individual. You name your friends suspect 1-4. You extract the DNA and run a gel electrophoresis. Can you identify the person who committed the crime? If not, can you rule anyone out?
Describe what is happening in the blood vessel (what you are measuring) during the systolic versus the diastolic blood pressure.
Systolic – higher pressure, force that blood exerts on artery wall as heart contracts, first Korotkoff sound
Diastolic – lower pressure, residual pressure on arteries as heart relaxes between beats,
Your instructor gives you whole milk and asks you to test it for the presence of three types of macromolecules. What tests would you perform and what would the results be (color changes)? Give enough details.
Carbohydrates – Benedict’s – orange-reddish
Lipids – Paper test (translucent) or alcohol emulsion test – (cloudy white)
Proteins – Biuret – violet (purple)
Temperature
pH
Concentration of enzymes
Concentration of substrates
Concentration of co-factors
Activators
Inhibitors
Phenol red is a ____________________ that turns _____________ in an acidic environment and is _____________ in a basic environment. We used it in one of our experiments to show that ________________________ was occurring in the tube with Elodea.
Phenol red is a ___pH indicator____ that turns _yellow__ in an acidic environment and is __red_ in a basic environment. We used it in one of our experiments to show that ___photosynthesis__ was occurring in the tube with Elodea.
Fermentation is a metabolic process that occurs in ______ conditions. When taking place in yeast cells, the two products are _____ and _____. When taking place in animal muscle cells, the product is ______.
Fermentation is a metabolic process that occurs in anaerobic conditions. When taking place in yeast cells, the two products are CO2 and ethanol (alcohol). When taking place in animal muscle cells, the product is lactate
Name the four lobes of the brain and state a function for two of them.
Parietal - sensory info, touch and pressure, taste, body awareness
Temporal - Hearing, sounds, memories, facial recognition
Occipital - vision