exam #1 Flashcards
(113 cards)
1
Q
define science
A
a way of knowing, a method to seek answers, a process of using observation and experiments to draw evidence-based conclusions
2
Q
define biology
A
the study of life
3
Q
list and describe the steps of the scientific method (process)
A
- observation
- hypothesis
- experiment
- analyze data
- conclusion
4
Q
define hypothesis
A
a testable and falsifiable explanation for a scientific observation or question
5
Q
define independent variable
A
the factor being deliberately changed
6
Q
define dependent variable
A
measured result of an experiment
7
Q
define randomized controlled trials
A
a controlled medial experiment in which subjects are randomly chosen to receive either an experimental treatment or a standard treatment
8
Q
define case control study
A
a type of epidemiological study to assess an association between an exposure and an outcome
9
Q
explain steps of well-designed experiment
A
a. includes a control group
b. includes an experimental group
c. experiment is known as a controlled experiment
10
Q
identify control group
A
experiences no experimental manipulation
11
Q
identify experimental group
A
experiences the experimental manipulation
12
Q
define cofounding variable
A
influences both the independent and the dependent variable
13
Q
define statistical significance
A
a measure of confidence that the results obtained are “real” and not due to chance
14
Q
define blind study
A
the participant doesn’t know if they received the placebo or the real treatment but the experimenter does
15
Q
define double-blind study
A
neither the participant nor the experimenter know weather they received the real treatment or the placebo
16
Q
define scientific theory
A
an explanation of the natural world that is supported by a large body of evidence and has never been disproved
17
Q
does science have the ability to “prove” something?
A
science cannot prove anything but it can create a substantial amount of evidence to support a claim
18
Q
what are anecdotes
A
conclusions informally vetted, inspired by evidence, based on personal experience, conclusions published on social media, conclusions are not reliable
19
Q
what is scientific evidence
A
hundred/thousands of date points examined, hypotheses are examined, data subjected to statistical analysis
20
Q
separating facts from conclusions
A
- facts are true and can be verified
- conclusions are developed from the facts
21
Q
distinguishing between correlation and causation
A
- correlation: a consistent relationship between two variables
- causation: the relationship because of cause and effect
- correlation between two variables does not prove that one variable causes the other
22
Q
what is peer review?
A
a review of an article by experts before publication to weed out sloppy research
23
Q
how to interpret science in the news
A
look at:
study size
model system
replication (can it be repeated)
hyped language
outside input
funding source
publication reputation
24
Q
define epidemiology
A
the study of patterns of disease in populations, including risk factors
25
define chemistry
the identification of the substances of which matter is composed
26
list & describe characteristics of living organisms
- grow: increase in size
- reproduce: produce new organisms
- maintain homeostasis: maintain a stable internal environment, even when external environment changes
- sense and respond to stimuli: for example, for towards sunlight or away from predators
- obtain and use energy: obtain energy from food, chemical reactions convert the energy into usable forms
27
what is matter composed of?
anything that takes up space and has mass
28
what are elements composed of?
atoms
29
what are atoms composed of?
protons, electrons, and neutrons
30
explain atomic structure
- has a nucleus (protons and neutrons)
- electrons are outside of the nucleus in the electron shell and create chemical bonds
31
what is indicated by the atomic number?
the number of protons in an atom
32
what is indicated by the mass number?
the number of protons plus neutrons
33
what is an isotope?
different forms of an element, vary by number of neutrons
34
what is an ion?
an electrically charged atom, the charge resulting from the loss or gain of electron
35
what atoms tend to form chemical bonds?
an atom that lacks electrons will form a chemical bond with an atom that can "spare" the outer electrons
36
name 3 main types of chemical bonds
1. covalent
2. ionic
3. hydrogen
37
how is a covalent bond formed?
a strong interaction resulting from the sharing of a pair of electrons between two atoms
38
how is an ionic bond formed?
a strong electrical attraction between oppositely charged ions formed by the transfer of one or more electrons from one atom to another
39
how is a hydrogen bond formed?
a weak electrical attraction between a partially positive hydrogen atom and an atom with a partial negative charge
40
what are the properties of water?
- water is sticky (cohesion/adhesion)
- water can abord a lot of energy (large liquid range)
- ice is less dense than liquid water (ice floats)
41
define solvent
a substance in which another substance dissolves
42
define solute
a dissolved substance
43
define solution
the mixture of solute and solvent
44
what is an acid?
higher concentration of hydrogen ions
45
what is a base?
higher concentration of hydroxide ions
46
what is a salt?
pairs of oppositely charged ions
47
what is the pH scale?
- the measure of the concentration of hydrogen ions in a solution
- ranges from 0-14, 7 being neutral, 14 being basic, 0 being acidic
48
what is the function of a buffer?
to resist the change of the pH
49
what are the properties of carbon?
- key component of the molecules of living organisms
- can form multiple covalent bonds
- can bond with up to 4 atoms
50
what are organic molecules?
molecules that have carbon-based backbones and at least on C-H bond
51
what are inorganic molecules?
molecules that lack carbon-based backbones and C-H bond
52
what is dehydration?
the removal of a water molecule to build dimers and polymers from monomers
53
what is hydrolysis?
the addition of a water molecule to breakdown a polymer into individual monomers
54
what are the four classes of organic molecules?
- carbohydrates
- proteins
- lipids
- nucleic acids
55
what is a macromolecule?
large organic molecules, composed of monomers
56
what are monomers?
one chemical subunit of a polymer
57
what are polymers?
a molecule made up of monomers linked together in a chain
58
what is a monosaccharide?
a monomer
59
what is an oligosaccharide?
a small polymer
60
what is a polysaccharide?
a large polymer
61
what are the functions of carbohydrates?
good for energy storage
62
what are carbohydrates made of?
repeating subunits of monomers
63
what are complex sugars?
larger molecules that take longer to breakdown
64
what are simple sugars?
good for a quick boost of energy
65
how are simple sugars and polysaccharides different?
simple sugars are only good for a quick boost of energy whereas polysaccharides are larger and take longer to breakdown therefore giving longer periods of energy
66
what are the three types of lipids and their functions?
- triglycerides: used for long-term energy storage
- phospholipids: form the cell membrane
- steroids: help with cell membranes and chemical signaling
67
difference between saturated and unsaturated fatty acids
saturated - solid at room temperature
unsaturated - liquid at room temperature
68
what are proteins composed of?
folded polymers which are made up of repeating units of amino acids
69
explain the four levels of protein structure
primary: linear sequence of amino acids
secondary: repeated patterns formed by hydrogen bonds
tertiary: 3-D folded pattern of polypeptide
quaternary: protein composed of multiple polypeptides
70
various functions of proteins in the body
- structural (hair)
- enzymes (increase the amount of energy required of a chemical reaction)
71
what is an enzyme?
proteins
72
how do enzymes work?
they lower the activation energy of the reaction which in turn increases the rate of the reaction
73
define specificity
enzyme will act only on molecules that have a specific, functional group
74
define substrate
molecule that an enzyme reacts with
75
define product
molecule that is produced by the chemical reaction catalyzed by the enzyme
76
define cofactor
addition of another non-protein molecule to function as an enzyme
77
define coenzyme
organic compounds required by many enzymes for catalytic activity
78
what does the denaturation of proteins mean?
the structure of the protein is exposed to changes
79
what happens when the protein denatures?
the hydrogen bonds present in the protein get disturbed
80
what are nucleic acids composed of?
linked up nucleotide subunits
DNA & RNA
81
monomer of a nucleic acid
neuclotides
82
polymer of a nucleic acid
DNA & RNA
83
how do DNA and RNA differ?
DNA has two chains of bonded nucleotides (A, C, G, T)
RNA has one chain of bonded nucleotides (A, C, G, U)
84
what are the principles stated by the cell theory?
- all living things are made of one or more cells
- the cell is the basic unit of life
- every new cell comes from the division of a pre-existing cell
85
how are eukaryotic cells different from prokaryotic cells?
have membrane-bound organelles, including a nucleus, found in humans
86
how permeable is the plasema membrance?
semipermeable
87
what components are found as part of the plasma membrane?
lipids(phopholipids), proteins, carbohydrates
88
how does passive transport differ from active transport?
- no energy required
- moves from an area of higher concentration to one of lower concentration
89
list and describe the different types of passive transport
- diffusion: natural tendency of dissolved substances to move from an area of higher concentration to one of lower concentration
- facilitated diffusion: substances more "downhill" by a transport protein form an area of higher concentration to an area of lower concertation
- osmosis: water's tendency to move across cell membrane
- filtration: results in the separation of solid matter from a liquid
90
what transport processes require membrane proteins?
facilitated diffusion, active transport
91
what is osmosis?
water's tendency to move across cell membrane
92
how to cells react in a isotonic solution
there is no net movement of water direction that will tend to even out the solute concentration on each side of the membrane
93
how to cells react when placed in a hypotonic solution?
takes up water and swells
94
how to cell react when placed in a hypertonic solution?
lose water and shrivel
95
what occurs in endocytosis?
cell use the cell membrane to engulf large items and bring it into the cell wrapped in an endocytic vesicle
96
what occurs in exocytosis?
a secretory vesicle merges with the cell membrane, and its contents are ejected from the cell
97
what is the role of the receptor protein?
to trigger endocytosis when they bind to certain molecules outside the cell
98
describe active transport
- requires energy
- low to high concentration
- against concentration scale
- receives help from transport proteins
99
why is the sodium-potassium pump important?
helps maintain cell potential and regulates cellular volume
100
how does a potassium pump work?
moves potassium into the cell and sodium ions out the cell, against the concentration gradient
101
what is the role of the nucleus?
interprets genetic information
102
what is the function of the ribosomes?
read the genetic information and make proteins
103
where are ribosomes located?
in the cytoplasm
104
what is the function of the smooth/rough ER?
synthesize proteins and lipids
105
what are vesicles?
tiny sacs that transport material within or outside the cell
106
list four different types of vesicles
- vacuoles
- lysosomes
- transport vesicles
- secretory vesicles
107
what is the function of the mitochondria?
extract energy from food, convert it into a useful form
108
define lysosomes
full of digestive enzymes, break down worn-out cell parts and food molecules
109
define peroxisomes
converts toxic hydrogen peroxide into water and oxygen
110
what is the cytoskeleton made up of?
protein fibers
111
what is endosymbiosis?
free-living prokaryotic cells engulfed other free-living prokaryotic cells billons of years ago, forming the mitochondria and chloroplasts
112
mechanism of penicillin
weakens the bacterial cell wall, so that it can no longer withstand the pressure of the incoming water
113
mechanism of streptomycin
interferes with protein synthesis by bacterial ribosomes
