Lab Review Flashcards
what is the scientific method
a method of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.
steps of the scientific method
- Make an observation.
- Ask a question.
- Form a hypothesis, or testable explanation.
- Make a prediction based on the hypothesis.
- Test the prediction.
- Iterate: use the results to make new hypotheses or predictions.
what is a hypothesis
a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.
comparative vs controlled experiments
comparative = Involves collecting data on different populations/organisms under different conditions (ex. Times of year, Locations), to make a comparison.
controlled = an experiment in which all the variable factors in an experimental group and a comparison control group are kept the same except for one variable factor in the experimental group that is changed or altered
independent vs dependent vs standardized variables
independent = a variable (often denoted by x ) whose variation does not depend on that of another.
dependent = a variable (often denoted by y ) whose value depends on that of another.
standardized = a variable that has been rescaled to have a mean of zero and a standard deviation of one
conversion of m and nm
1m=100cm 10^2
1000mm 10^3
1000000um 10^6
1000000000nm 10^9
what are are the four major macromolecules
lipids, carbohydrates, proteins, and nucleic acids
what is osmosis
a process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one
hypertonic means
a solution has a higher concentration of solute than is found in the cells and the water leaves the cell
hypotonic means
a solution has a lower solute concentration than the cells and the cells take up water
isotonic means
an extracellular solution which contains the same concentration as the solute
what happens to a cell in a hypertonic solution
in plant and animal the cells shrink
what happens to a cell in a hypotonic solution
in plant they swell and increase turgor pressure and in animal they burst
what happens to a cell in a isotonic solution
nothing
what is ATP
the immediate energy source for most of a cells activities
what is potential energy in a cell
the energy stored in bonds of the. molecule
number of carbons in glucose and fructose
6
number of carbons in sucrose
12
why do we make yeast and water a control when comparing different carbohydrates
because water does not have any sugar/ carbon in it which yeast needs to grow
what part of a phospholipid is hydrophilic
the phosphate group head
what part of a phospholipid is hydrophobic
the fatty acid tail
how does a spec work
it measures the absorbance
what is an enzyme
a catalyst that speeds up chemical reaction without being used in up in the process
what is a catalyst
they are very specific and they react with a certain substrate to catalyze a narrow class of chemical reactions
what is hydrogen peroxide in our enzyme lab
the substrate for our enzyme
what is photosynthesis
the process by which plants and certain algae synthesize simple organic molecules from carbon dioxide and water
what is replication
the process of copying DNA to make new DNA
what is translation
the final step to turn the DNA message into a protein product. The mRNA matches to anticodons on tRNA to bring specific amino acids based on the genetic code
what is transcription
this occurs on a regular basis in every single cell if the body and this is the process of using the info stored in DNA to make mRNA
why does starch have the most potential energy with yeast
it has repeating glucose units
stains combine with what to increase contrast of cells under a microscope
low power, stage all the way up
why is staining a step often used when looking at cells under a microscope
increases contrast
when you begin to focus the microscope, which combination below is correct
low power, stage all the way up
how do we obtain the major macromolecules our bodies need
common foods
indicators can test for the presence of
sugars, fats, and proteins
in diffusion substances move from a _______ concentration to a ________ concentration
higher, lower
Biurets reagent is an indicator for the presence of
proteins
Benedicts reagent is an indicator for the presence of
sugar
if a cell crenates, it
shrinks
why do we say that a 12 carbon sugar has more potential energy than a 6 carbon sugar
more carbons mean more energy and 12 carbons has more potential energy because not all organisms could break down the 12 C to release the energy
what is the relationship between variance and standard deviation
take the square root of variance to get SD
give the equation to calculate enzyme activity rate
final absorbance reading reading - initial absorbance reading / number of seconds
what does an optimal pH give
the highest enzyme activity
the function of peroxidase is to turn hydrogen peroxide into
water and oxygen
photosynthesis uses carbon dioxide and water to make the final product
glucose
why/ how does pH affect enzyme activity
alters structure and lowers activity
why do leaf disks float in the solution contains sodium bicarbonate but not in the solution without sodium bicarbonate
bicarbonate is the carbon source - without it no photosynthesis, no oxygen, no floating
photosynthesis produces oxygen. What is the process that consumes oxygen and produces ATP for the cell
cellular respiration
what is the purpose of soap in the solutions for the leaf disk assay
wets the hydrophobic leaf surface allowing solution to get into the leaf
stage of meiosis I in which the homologous pairs line up on the equilateral plate
metaphase I
stage of meiosis in which the chromosomes gather into nuclei, and the original cell divides
telophase I
stage of meiosis II in which the chromosomes gather into nuclei and the cells divide
telophase II
stage of meiosis I in which the chromatin begin to condense following interphase
early prophase I
stage of mitosis in which daughter chromosomes reach the poles, the nuclei re-form, and the cell again enters interphase
telophase
where in the mouth are taste receptors located
taste buds
papillae are visible to the naked eye
true