Ch 1.5 and Appendix B Flashcards
1
Q
5 steps of Biological Studies
A
- Experimental Design
- Data Collection
- Organize and Visualize Data
- Summarize the Data
- Inferential Statistics
2
Q
Features of a Sample
A
Should be representative of a larger population
3
Q
Quantitative Variables
A
Variables on a numerical scale (ex: temperature, size, etc…)
4
Q
Discrete Variables
A
Quantitative variables that only take on whole number values
5
Q
Continuous Variables
A
Quantitative variables that take on only fractional values
6
Q
Categorical Variables
A
Variables that take categories as values (Blood Types)
7
Q
Ordinal Variables
A
Categorical variables with natural ordering (ex: final grades in Bio - A,B,C,D,F)
8
Q
Frequency Distribution
A
Lists all possible values and the number of occurrences of each value in the sample
9
Q
Histograms
A
Depict frequency distributions for quantitative data.
10
Q
Scatter Plot
A
Used most often to compare two quantitative variables
11
Q
Linear Relationship
A
When the points of two variables fall on a straight line in a scatter plot graph
12
Q
Statistic
A
Numerical quantity calculated from data
13
Q
Descriptive statistics
A
Quantities that describe general patterns in data
14
Q
Describing categorical data
A
Use proportions
15
Q
Mean
A
Aveage
16
Q
Median
A
The number literally in the middle. If there are an even amount of numbers (2 middle numbers) you take the average of those two numbers
17
Q
Mode
A
The most commonly occur number
18
Q
Measures of Dispersion
A
Tell us how much values differ from eachother
19
Q
Standard Deviation
A
Calculates the extent to which the data are spread out form the mean
20
Q
Correlation Coeffecient
A
Quantifies the strength of the relationship between two quantitative variables using a single value
21
Q
Linear Regression
A
Fits a straight line to data, minimizes residuals
22
Q
Residuals
A
The vertical distances between the points in the scatter plot and the linear regression line itself
23
Q
Alternative Hypothesis
A
The opposite of the Null Hypothesis
24
Q
Bayesian inference
A
A statistical approach that makes it easier to favor a new hypothesis
25
Frequentist Statistics
Traditional statistical methods
26
Type I Error
Rejecting the null hypothesis when it is actually true
27
Type II Error
Accept the null hypothesis when it is actually false
28
P-value
The likelihood that chance alone would produce data that differ from the null hypotheses as much as our data differ from the null hypothesis
29
Significance level
A p-value threshold.
The null hypothesis can only be rejected when the P-value is less than or equal to the significance level (alpha = 0.05)
This limits Type I error to 5%
30
Power
The probability that we will correctly reject the null hypothesis when it is false.
The higher the power, the less likely we are to make a Type II error
31
3 Ways to Increase Power
1. Decrease the significance level (alpha) - the higher the value of alpha, the harder it is to reject the null, even if it is actually false
2. Increase the sample size
3. Decrease variability in the sample - the more variation there is in the sample, the harder it is to discern a clear effect when it actually exists
32
Natural History
The characteristics of a group of organisms (How they get their food, reproduce, behave, regulate their bodies) and how they interact with other organisms
33
Quantify
Assigning numerical values to observations through measurement
34
Hypothesis
A tentative answer to a question, from which TESTABLE predictions can be generated
35
Deductive logic
Used to make predictions based on the hypothesis. Starts with a believed to be true statement and goes on to predict what facts would have to be true to be compatible with the statement
36
Controlled Experiment
Sample is divided into groups and these groups are exposed to manipulations while one group serves as an untreated control. Data then tells if there are changes in a dependent variable as a result of the manipulations
37
Variable
In a controlled experiment, a factor that is manipulated to test its effect on certain phenomenon
38
Comparative Experiment
Data from various unchanged samples or populations are compared, but in which variables are not controlled or even identified
39
Null Hypothesis
The premise that any differences observed in an experiment are simply a result of random differences that arise from drawing two samples from the same population
40
Data
Quantified observations
41
Atom
Smallest unit of a chemical element.
42
Neutron
one of the three fundamental particles, mass slightly larger than a proton and no electrical charge
43
Nucleus
centrally located compartment of eukaryotic cells that is bounded by a double membrane
44
Electrons
negatively charged particles
45
Protons
a subatomic particle with a single positive charge
46
Element
a pure substance that contains only one kind of atom
47
Atomic number
number of protons
48
Bohr Model
a model for atomic structure (atom-largely empty space with a central nucleus)
49
Electron Shells
electrons in orbits around the nucleus
50
Molecules
atoms bonded together into stable conditions
51
Chemical bond
attractive force that links two atoms together in a molecule
52
Ionic Bonds
atoms must gain or lose one or more electrons to achieve stability
53
Covalent bonds
strong bonds that form when atoms share electrons
54
Ion
electrically charged particle that forms when an atom gains or loses one or more electrons
55
Cations
Positively charged ions
56
Anions
Negatively charged ions
57
Electronegativity
the attractive force that an atomic nucleus exerts on electrons in a covalent bond
58
Polar Covalent Bond
a covalent bond in which the electrons are drawn to one nucleus more than the other
59
Hydrogen Bond
a weak electrostatic bond which arises from the attraction between the slight positive charge on the hydrogen atom and slight negative charge on oxygen or nitrogen atom
60
What are important properties of H2O?
High Heat Capacity
Cohesion
Adhesion
Solvent
61
Heat of Vaporization
The hydrogen bonding in water gives water this property. It means that it takes a lot of heat to change water from its liquid to its gaseous state
62
Hydrophilic
"water loving" polar molecules that become separated and surrounded by water molecules in an aqueous solution
63
Hydrophobic
Non-polar molecules that tend to aggregate together in an aqueous solution rather than with the polar water molecules.
64
Hydrocarbon molecules
Molecules that only contain hydrogen and carbon atoms. They are also non-polar
65
Functional groups
small groups of atoms that are consistently found together in different biological molecules
66
Hydroxyl group
Polar. Hydrogen bonds with water to help dissolve molecules. Enables linkage to other molecules by condensation
67
Aldehyde
C=O group is very reactive. Helps with building molecules and in energy releasing reactions
68
Keto
C=O group is important in carbohydrates and in energy reactions
69
Carboxyl
Acidic. Ionizes in living tissue to create -COO and H+. Enters into condensation reactions by giving up -OH
70
Amino
Basic. Accepts H+ in living tissues to form NH3+. Enters into condensation reactions by giving up H+
71
Phosphate
Negatively charged. Enters into condensation reactions by giving up OH-. When bonded to another phosphate, hydrolysis releases a lot of energy
72
Sulfhydryl
By giving up H, two SH groups can react to form a disulfide bridge thus stabilizing protein structure.
73
Macromolecules
Large molecules that are formed by covalent linkages of smaller molecules. 4 kinds in living things: proteins, carbohydrates, nucleic acids and lipids
74
Polymers
Other than lipids, the other three macromolecules are constructed by the covalent bonding of smaller molecules called monomers
75
Monomers
A smaller molecule
76
Oligomers
the linking of a few monomers (covalently bonded)
77
Proteins
formed from different combinations of 20 amino acids, all of which have chemical similarities
78
Carbohydrates
can be big molecules, and are formed by linking together chemically similar sugar monomers (monosaccharides) to form polysaccharides
79
Nucleic Acids
formed from four kinds of nucleotide monomers linked together in long chains
80
Lipids
form large structures from a limited set of smaller molecules, but in this case non-covalent forces maintain the interactions between the lipid monomers
81
Condensation
the removal of water links monomers together
82
Hydrolysis
the addition of water breaks a polymer into monomers
83
Carbohydrate Purposes (4)
- Source of stored energy that can be released an used by organisms
- Transport stored energy within organisms
- They function as structural molecules (provide shape)
- They serve as recognition or signaling molecules that trigger specific responses
84
Monosaccharides
simple molecules that contain up to 7 carbon atoms (carbon, hydrogen and oxygen.
85
Pentose
five-carbon sugars (ribose and deoxyribose)
86
Hexose
all have the formula C6H12O6 (glucose, fructose, mannose and galactose
87
Glycosidic linkages
the way of bonding monosaccharides. Monosaccharides are covalently bonded by condensation reactions that form these linkages
88
Disaccharide
a single glycosidic linkage between 2 monosaccharides
89
Oligosaccharides
contain a few monosaccharides that are bound together by glycosidic linkages. Often covalently bonded to proteins and lipids on the outer surfaces of cells.
90
Polysaccharides
Large polymers of monosaccharides that are bound together by glycosidic linkages. Not necessarily linear.
91
Glycogen
a water-insoluble, polymer of glucose that stores much of the energy in animals (hydrolyzed to allow the energy to break free)
92
Cellulose
a polysaccharide of glucose. Its linkages are arranged so that it is a very stable molecule (good for being structural material)
