Midterm Review Flashcards
(157 cards)
1
Q
Light
A
electromagnetic radiation that can be detected by the human eye
2
Q
Photon
A
particles which transmit light
3
Q
electromagnetic radiation
A
energy that is transmitted at the speed of light through oscillating electric magnetic fields
4
Q
pigment
A
substanced produced by living organisms that have a colour resulting from selective colour absorption
5
Q
wavelength
A
horizontal distance between the crests or between the troughs of two adjacent light waves
6
Q
action spectrum
A
a graph of the rate of biological effectiveness plotted against wavelength of light
7
Q
absorption spectrum
A
the range of a pigments ability to absorb various wavelengths of light
8
Q
photoreceptors
A
special cells in the retina that are responsible for converting light signals sent to the brain; rods and cones
9
Q
eye
A
each pair of globular organs which allows animals to see
10
Q
rhodopsin
A
a pigment in rod cells which causes light sensitivity
11
Q
retina
A
produced visual images in the eye
12
Q
circadian rhythms
A
24 hour biological clock found in many species
13
Q
bioluminescence
A
the production and emission of light by a living organism
14
Q
fluorescence
A
material that absorbs light at one wavelength and emits light ar a longer wavelength
15
Q
the most common photoreceptor for light sensing
A
rhodopsin
16
Q
possesses enough energy to damage biological molecules
A
short wavelength ultraviolet (UV) radiation
17
Q
ecological light pollution
A
excessive artificial light at night which can harm night dwelling organisms
18
Q
cell theory
A
- are organisms are made of cells
- cells are the basic units of life
- cells come from pre-existing cells that may have multiplied
19
Q
ATP
A
adenosine triphosphate; main energy source that cells use to do their work
20
Q
RNA
A
single stranded nucleic acid containing ribose sugar
21
Q
DNA
A
one of 3 essential macromolecules; DNA makes RNA protein
22
Q
proteins
A
nutrients the body uses to build and maintain its cells and tissues
23
Q
prokaryotes
A
cells that do not contain a nuclei; unicellular organisms
24
Q
eukaryotes
A
organisms made up of one or more cells that have a necleus and membrane bound organelles
25
reducing atmosphere
an atmospheric condition in which oxidation is prevented by removal of oxygen and other oxidizing gases or vapours, which may contain actively reducing gases such as hydrogen and carbon dioxide
26
oxidizing atmosphere
an atmosphere that contains molecular oxygen
27
miller-urey experiment
experiment that found organic molecules can form in a strongly reducing atmosphere
28
protobionts
collections of abiotically produced molecules surrounded by a membrane-like structure
29
ribozymes
RNA molecules that function as enzymes
30
stromatolites
oldest known fossils formed from many layers of bacteria and sediment
31
panspermia hypothesis
building blocks for life came from an asteroid or meteor
32
nucleus
part of the cell containing DNA and RNA and is responsible for growth and development
33
nucleoid
a dense region of DNA in a prokaryotic cell
34
theory of endosymbiosis
this theory states that cell organelles, like mitochondria, were once tiny, free living organisms that took up pernament residence inside larger prokaryotic organisms
35
vesicles
small membrane sacs that specialize in moving products into, out of, and within a cell
36
exocytosis
process of vesicles fusing with the other plasma membrane and releasing their contents to the outside of the cell
37
endocytosis
process by which a cell takes material into the cell by infolding of the cell membrane
38
endoplasm resticulum
a cell structure that forms a maze of passageways in which proteins and other materials are carried from one part of the cell to another
39
golgi complex
a cell organelle that helps make and package materials to be transported out of the cell
40
mitochondria
organelle that is the site of ATP/energy production
41
chloroplast
an organelle found in plant and algae cells where photosynthesis occurs
42
cytoskeleton
a network of long protein strands in the cytosol that helps support the cell
43
microtubule
a hollow rod composed of tubulin proteins that make up part of the cytoskeleton eukaryotic cells
44
intermediate filament
a component of the cytoskeleton that includes filaments intermediate in size between microtubules and microfilaments
45
microfilament
long, thin fibers that function in the movement and support of the cell
46
flagella
a slender threadlike structure, that allows bacteria, and sperm to swim
47
9+2 structure
flagella and cilia have 9+2 tubule arrangements; 9 fused microtubules, 3 unfused microtubules
48
the earliest life forms
anaerobic prokatyotes
49
Biodiversity
the variety of life in the world or in a particular habitat or ecosystem
50
autotroph
an organism that is able to form nutritional organic substances from simple inorganic substances such as carbon dioxide
51
heterotroph
organism that obtains energy from the food it consumes; also called a consumer
52
chemotroph
an organism that gets its energy from chemicals taken from the environment
53
phototroph
an organism that gets its energy from sunlight
54
selection
a process in which environmental or genetic influences determine which types of organism thrive better than others
55
evolution
the gradual chance in a species over time
56
adaptive radiation
the diversification of a group of organisms into forms filling different ecological niches
57
biosphere
part of earth in which llife exists including land, water, and air
58
solar radiation
radiant energy emitted by the sun from a nuclear fusiom reaction that creates electromagnetic energy
59
seasonality
a repeated pattern of spikes and drops in weather at certain times of the year
60
air circulation
air is always trying to equalize pressure and temperature
61
coriolis effect
the effect of earths rotation on the direction of winds and currents
62
adiabatic cooling
the cooling effect of reduced pressure on air as it rises higher in the atmosphere
63
maritime climate
temperature range is small, and precipitation is high
64
continental climate
dry with very hot summers and very cold winters
65
monsoon
seasonal wind
66
microclimate
climate within an area which significantly differs from the climate of the surrounding area
67
producers
organisms that make their own food, such as plants
68
consumers
an organism that obtains energy and nutrients by feeding on other organisms or their remains
69
decomposers
organisms that break down the dead remains of other organisms
70
potential energy
stored energy that results from the position or shape of an object
71
kinetic energy
the energy an object has due to its motion
72
thermodynamics
the transfer of enrgy from one plaec to another and one form to another
73
entropy
a measure of disorder or randomness
74
enthalpy
the heat content of a system at constant pressure
75
free energy
energy that is available to do work
76
spontaneous reaction
energy that will proceed without any outside energy
77
exothermic
chemical reaction in which energy is primarily given off in the form of heat
78
endothermic
a reaction that ABSORBS energy in the form of heat
79
catabolic pathway
a metabolic pathway that releases energy by breaking down complex molecules to simpler compounds
80
anabolic pathway
a metabolic pathway that consumes energy to synthesize a complex molecule from simpler compounds
81
energy coupling
the use of energy released from an exergonic reaction to drive an endergonic reaction
82
enzymes
proteins that speed up chemical reactions
83
activation energy
the minimum amount of energy needed to start a chemical reaction
84
active site
a region of an enzyme that binds to a protein or other substance during a reaction
85
co-factor
non-protein compound that interacts with another substance to facilittate a transformation
86
co-enzyme
a small molcule, sometimes a vitamin, essential for the activity of some enzymes
87
non-competitive inhibition
substances that ttach to the binding site of an enzyme other than active site, causing a loss of affinity for its substrate
88
allosteric regulation
when a proteins function at one site is affected by the binding of a regulatory molecule to a seperare site
89
feedback inhibition
a method of metabolic control in which the end product of a metabolic pathwat acts as an inhibitor of an enzyme within that pathway
90
what are the two forms that energy exists in
potential and kinetic energy
91
two forms of metabolic reaction
catabolic reaction (release energy) and anabolic reaction (use energy)
92
plasma membrane
the membrane at the boundary of every cell that acts as a selective barrier
93
fluid mosaic model
structural model of the plasma membrane where molecules are free to move within a lipid bilayer
94
mombrane asymmetry
lipids are unequally distributed between leaflets
95
phospholipids
a lipid containing a phosphate group in its molecule
96
hydrophillic
attracted to water
97
hydrophobic
water fearing
98
amphipathic bilayer
contains both polar and nonpolar parts
99
membrane fluidity
the property by which most of the plasma membrane lipids and proteins easily rotate and move side ways in their own hald of the lipid bilayer
100
integral membrane proteins
proteins that are at least partially embedded in the plasma membrane
101
peripheral membrane proteins
proteins associated with but not embedded within the plasma membrane
102
cholesterol
a sterol lipid found in body cells and animal products
103
passive transport
requires NO ENERGY; movement of molecules from high to low gradient
104
channel proteins
provide corridors that allow a specific molecule or ion to cross the membrane
105
facilitated diffusion
movement of specific molecules across cell membranes through protein channels
106
osmosis
diffusion of water across a selectively permeable membrane
107
active membrane transport
requires ATP
108
proton pump
an active transport protein that uses ATP to transport hydrogen ions out of a cell AGAINST their concentration gradient
109
exchange diffusion
a secondary active transport mechanism in which a molecule moves through a membrane channel into a cell and powers the active transport of a second molecule out of a cell
110
electrochemical gradient
the diffusion gradient of an ion, which is affected by the concentration difference of an ion across a membrane
111
aquaporins
water channel proteins
112
symport
two molecules travel in the SAME direction
113
antiport
two substances move in OPPOSITE directions
114
membrane potential
the voltage difference across a membrane
115
diffusion
movement of molecules from a higher concentration to a lower concentration
116
desaturases
adds double bonds
117
carrier proteins
a protein that transports substances across a cell membrane
118
exocytosis
release of substances out of a cell by the fusion of a vesicle with the membrane
119
endocytosis
cell takes in materal by the infolding of the cell membrane
120
receptor mediated endocytosis
uptake of specific molecules based on receptor proteins
121
pinocytosis
cell drinking ; takes in fluid along with particles
122
phagocytosis
cell eating ; takes in other cells or particles
123
cellular respiration
process that releases energy by breaking down glucose and other food molecules in the presence of oxygen
124
redox reaction
a chemical reaction involving the transfer of one or more electrons from one reactant to another ; oxidation reduction reaction
125
NADH
electron carrier that stores energy used to make ATP
126
Glycolysis
the breakdown of glucose by enzymes, releasing energy and pyruvic acid
127
citric acid cycle / krebs cycle
completes the breakdown of glucose
128
pyruvate oxidation
conversion of pyruvate to acetyl CoA and CO2 that occurs in the mitochondrial matrix in the presence of oxygen
129
oxidative phosphorylation
the production of ATP using energy derived from the redox reactions of an electron transport chain; third major stage of cellular respiration
130
electron transport chain
series of electron carrier proteins that shuttle high energy electrons duirng ATP generating reactions
131
chemiosmosis
the use of energy in a H+ gradient to drive cellular work
132
mitochondrion
singular version of mitochondria; makes energy
133
ATP synthase
enzyme that catalyzies the reaction that adds a high energy phosphate group to ADP to form ATP
134
ATP synthesis in cellular respiration occurs via
substrate level phosphorylation and oxidative phosphorylation
135
uncoupling
a dissociation between mitochondrial membrane potential generation and its use for mitochondria dependent ATP synthesis
136
anaerobic respiration
respiration that does NOT require oxygen
137
strict anaerobes
an organisms that can only live in environments that lack oxygen
138
strict aerobes
can only grow/survive in oxygen
139
faculative anaerobes
can survive with or without oxygen
140
fermentation
process by which cells release energy in the absense of oxygen
141
photosynthesis
conversion of light energy from the sn into chemical energy
142
light reactions
the steps in photosyntheiss that occur in the presence of light; converts solar energy into chemical energy of ATP and NADPH
143
dark reactions / calvin cycle
second step of photosyntheis where chemical energy is used to make sugar (glucose)
144
thylakoid
a memnrane system within the chloroplast that contains the components for photosynthesis
145
inductive resonance
the energy of the excited electron is transferred to a neighbouring pigments molecule and the first molecule returns to its ground state
146
carotenoids
an accessory pigment, either yellow or orange, found in the cholorplast
147
photosystem I
a light capturing unit in a chloroplasts thylakoid membrane; has two molecules of P700 chlorophyll
148
photosystem II
light capturing unit in chloroplast; has two molecules of P680 chlorophyll
149
antenna complex
part of a photosystem, containing an array of chlorophyll molecules and accessory pigments ; recieves light energy
150
reaction center
a complex of proteins and pigments that contains the primary electron acceptor
151
cyclic electron transport
in light reactions, the flow of electrons that produces ATP but does not produce NADPH or O2
152
rubisco
an enzyme in chloroplasts involved in fixing atmospheric carbon dioxdide during photosynthesis
153
photorespiration
a metabolic pathway that consumes oxygen, releases carbon dioxide, and does not generate ATP ; occurs on hot and dry days
154
C4 pathway
a carbon fixing process in which carbon dioxide is bound to a compound to form a four carbon intermediate
155
CAM pathway
a water conserving carbon fixing process ; CAM plants take in carbon at night and fix it into various organic compounds to be released during the day
156
PEP carboxylase
an enzyme that adds carbon dioxide to phosphoenolpyruvate (PEP) to from oxaloacetete
157
what are the two steps of photosynthesis
light reactions and dark reactions (calvin cycle)
