vocab Flashcards
(120 cards)
1
Q
micrometer
A
unit of measurement
2
Q
light microscope
A
uses visible light, the first thing that allowed intricate structures to be viewed, allows up to 1000x magnification, requires a bright light, the specimen has to be prepared so light can pass through it, need a set of lenses
3
Q
fluorescence microscope
A
instrument used to visualise a specimen that has been labelled with fluorescent dye, samples are illuminated with a wavelength of light that excited the dye, cause it to fluoresce
4
Q
electron
A
negatively charged subatomic particles that occupies space around a atomic nucleus
5
Q
microscope
A
instrument for viewing extremely small objects
6
Q
prokaryote
A
category of living cells distinguished by absence of nucleus
7
Q
eukaryote
A
organism whos cells have distinct nucleus and cytoplasm
8
Q
archaea
A
1 domain of prokaryotes, found in harsh environments
9
Q
bacteria
A
other domain of prokaryotes, make up most prokaryotes that are familiar from everyday life
10
Q
actin filament
A
thin, flexible protein filaments made from a chain of globular actin molecules, part of eukaryotic cells, cytoskeletal element essential for cell movement and contraction of muscle cells
11
Q
cell wall
A
mechanically strong fibrous later deposited outside the plasma membrane of some cells, prominent in plants, bacteria, algae, fungi, not prominent in animals
12
Q
chromosomes
A
long, threadlike structure composed of DNA and proteins that carries genetic information
13
Q
cytoplasm
A
contents of a cell contained within plasma membrane, in eukaryotic cells, outside nucleus
14
Q
cytoskeleton
A
system of protein filaments in cytoplasm of eukaryotic cells that gives cells shape and capacity for directed movement
15
Q
cytosol
A
contents of main compartment of cytoplasm excluding membrane-enclosed organelles
16
Q
endocytosis
A
process where cells take in materials through invagination of plasma membrane, surrounding ingested material in a membrane-enclosed vesicle
17
Q
exocytosis
A
process where molecules are secreted from a eukaryotic cell
18
Q
extracellular matrix
A
complex network of polysaccharides and proteins secreted by cells
19
Q
protozoans
A
a free-living, nonphotosynthetic, single-celled, motile eukaryote
20
Q
intermediate filaments
A
fibrous cytoskeletal elements, forms ropelike networks, helps cells resist tension applied
21
Q
microtubule
A
long, stiff, cylindrical structure composed of protein tubulin, used by eukaryotic cells to organise cytoplasm and guide intracellular transport of macromolecules
22
Q
model organsim
A
living things selected for intensive study as a representative of a large group of species
23
Q
nuclear envelope organelle
A
double membrane surrounding the nucleus
24
Q
photosynthesis
A
process where sunlight energy drives synthesis of organic molecules from carbon dioxide and water
25
plasma membrane
protein-containing lipid bilayer surrounding living cells
26
Nucleus
Contains chromosomes (DNA)
27
Ribosomes
Synthesise proteins
28
Mitochondria
Transform energy from food to produce ATP (cellular energy molecule)
29
Chloroplasts
Carry out photosynthesis (in plant cells only)
30
Endoplasmic Reticulum
Continuous with nuclear membrane - produces membranes, membrane proteins and materials for secretion
31
Golgi apparatus
Modifies and packages molecules from ER destined for transport elsewhere
32
Lysosomes
Intracellular digestion (breakdown unwanted molecules for recycling/nutrients)
33
Peroxisomes
Safe place to carry out reactions involving hydrogen peroxide to inactivate toxins
34
Transport vesicles
Shuttle materials from one organelle to another and to the outside of the cell
35
Amino acid
Small organic molecule containing both an amino acid and a carboxyl group, building block for proteins
36
Atom
Smallest particle of an element, retains distinct chemical properties, consists of positively charged nucleus which surrounds a cloud of negatively charged electrons
37
Condensation reaction
Chemical reaction in which a covalent bond is formed between 2 molecules as water is expelled, used to build polymers
38
Covalent bond
Stable chemical link between 2 atoms produced by sharing 1 or more pairs of electrons
39
DNA
Double stranded polynucleotide formed from 2 separate chains of covalently linked deoxyribonucleotide units, serves as cells store of genetic information
40
Disaccharide
Sugars whose molecules contain 2 monosaccharide reactions
41
Electron
Negatively charged subatomic particles that occupies space around a atomic nucleus
42
Electrostatic attraction
Force that draws together oppositely charged electrons
43
Fatty acid
Molecule consisting of carboxylic acid attached to a long hydrocarbon chain, energy for metabolism
44
Hydrogen bonds
Weak noncovalent interaction between positively and negatively charged atoms
45
Hydrolysis
The chemical breakdown of a compound due to reaction with water
46
Hydrophilic
Part of a molecule that readily formed hydrogen bonds with water, allowing it to readily dissolve
47
Hydrophobic
Nonpolar, uncharged molecules that forms no hydrogen bonds with water molecules, doesn’t dissolve
48
Hydrophobic interactions
Noncovalent interactions that forces together the hydrophobic portions of dissolved molecules to minimise their disruption of the hydrogen-bonded network of water, causes membrane phospholipids to self-assemble into a bilateral and helps to fold protein into a compact, globular shape
49
Inorganic molecules
Not composed of carbon atoms
50
Lipid bilayer
Thin layer of closely juxtaposed sheet, composed of phospholipid molecules, forms structural basis for all cell membranes
51
Macromolecule
Polymer built from covalently linked subunits includes proteins, nucleic acid and polysaccharides with a molecular mass of greater than few thousand daltons
52
Monomer
Small molecule that can be linked to others of a similar type to form a larger molecule
53
Monosaccharide
Simplest sugars
54
Noncovalent bonds
Chemical association, no electron sharing, relatively weak but can sum together to produce strong, highly specific interactions between molecules
55
Nucleotide
Basic building block of nucleic acids (DNA, RNA)
56
Organic molecules
Chemical compound with carbon and hydrogen
57
Polar
Molecule/bond which electrons distributed unevenly
58
Polymer
Long molecule made by covalently linking multiple identical or similar subunits
59
Protein
Macromolecule built from amino acids that provides cells with their shape and structure
60
Proton
Positively charged particle found in nucleus of every atom
61
RNA
Molecule produced by transcription of DNA, single-stranded, polynucleotide composed of covalently linked ribonucleotide subunits, serves a variety of informational structural, catalytic and regulatory functions in cells
62
Subunit
Monomer that forms part of a larger molecule, such as a amino acid residue in a protein
63
Sugar
Substance made of carbon, hydrogen and oxygen
64
Van de Waals attractions
Weak noncovalent interaction, due to fluctuating electrical charges, that come into play between 2 atoms within a short distance of each other
65
activation energy
the energy that must be acquired by a molecule to undergo a chemical reaction
66
anabolism
set of metabolic pathways by which large molecules are made from smaller ones
67
biosynthetic pathways
anabolic pathways, use energy from catabolism to drive the synthesis of large molecules
68
catabolism
set of enzyme-catalysed reactions by which complex molecules are degraded to simpler ones with the release of energy; intermediates in these reactions are sometimes called catabolites
69
catalyst
substance that accelerates a chemical reaction by lowering its activation energy; enzymes perform this role in cells
70
cellular respiration
process by which cells harvest the energy stored in food molecules; usually accompanied by the uptake of oxygen and the release of carbon dioxide
71
dehydrogenation
oxidations, proton and electron movement
72
entropy
thermodynamic quantity that measures the degree of disorder in a system
73
enzyme
a protein that catalyses a specific chemical reaction
74
equilibrium
state in which the forward and reverse rates of a chemical reaction are equal so that no net chemical change occurs
75
free energy
energy that can be harnessed to do work, such as driving a chemical reaction
76
free energy change
in a chemical reaction, the difference in free energy between reactant and product molecules; a large negative change value indicates that the reaction has a strong tendency to occur
77
hydrogenation
reductions, proton and electron movement
78
metabolism
the sum total of the chemical reactions that take place in the cells of a living organism
79
oxidation
removal of electrons from an atom, as occurs during the addition of oxygen to a carbon atom or when a hydrogen is removed from a carbon atom; can also refer to a partial shift of electrons between atoms linked by covalent bonds
80
reduction
addition of electrons to an atom, as occurs during the addition of hydrogen to a carbon atom or the removal of oxygen from it; can also refer to the partial shift of electrons between atoms linked by covalent bonds
81
substrates
a molecule on which an enzyme acts to catalyse a chemical reaction
82
activated carriers
a small molecule that stores energy or chemical groups in a form that can be donated to many different metabolic reactions
83
ADP
nucleoside diphosphate produced by hydrolysis of the terminal phosphate of ATP
84
ATP
activated carrier that serves as the principal carrier of energy in cells; a nucleoside triphosphate composed of adenine, ribose and 3 phosphate groups
85
biosynthesis
an enzyme-catalysed process by which complex molecules are formed from simpler substances by living cells
86
coupled reaction
linked pair of chemical reactions in which free energy is released by one reaction that serves to drive the other reaction
87
activation energy
the energy that must be acquired by a molecule to undergo a chemical reaction
88
double reciprocal plot
graphical representation of enzyme kinetics etc
89
enzyme-substrate complex
a temporary molecule formed when the enzyme and substrate are bonded together
90
Km
michaelis constant, the concentration of substrate at which an enzyme works at half its maximum velocity; serves as a measure of how tightly the substrate is bound
91
phosphorylation
any reaction that involves the transfer of a phosphate group to a molecule (eg. condensation reaction)
92
random walk
the path a molecule moves in during diffusion, moves one way then the other way
93
reaction velocity
how quickly substrate is consumed or how quickly product is formed
94
turnover number
the maximum number of substrate molecules than an enzyme can convert into product per second
95
Vmax
the maximum rate of an enzymatic reaction, reached when the active sites of all of the enzyme molecules in a sample are fully occupied by substrate
96
active site
region on the surface of an enzyme that binds to a substrate molecule and catalyses its chemical transformation
97
catalysis
the acceleration of a chemical reaction by a catalyst
98
competitive inhibitor
competes with a substrate for binding to an active site
99
conformational change
a change in the shape of a macromolecule
100
diffusion
process by which molecules and small particles move from one location to another by random, thermally driven motion
101
enzyme
a protein that catalyses a specific chemical reaction
102
feedback inhibition
a form of metabolic control in which the end product of a chain of enzymatic reactions reduces the activity of an enzyme early in the pathway
103
lysozyme
enzyme that servers the polysaccharide chains that form the cell wall of bacteria; found in many secretions including saliva and tears, where it serves as an antibiotic
104
negative regulation
the process of regulating gene expression by inhibiting the expression of that specific gene
105
non-competitive inhibitor
specific type of enzyme inhibition characterised by an inhibitor binding to an allosteric site resulting in decreased efficacy of the enzyme
106
positive regulation
To begin the transcription process, the activator proteins bind to the operator on mRNA
107
regulatory site
The site to which the effector binds
108
transition state
transient structure that forms during the course of an chemical reaction; in this configuration, a molecule has the highest free energy; it is no longer the substrate, but is not yet the product
109
action potential
travelling wave of electrical excitation caused by rapid, transient, self-propagating depolarisation of the plasma membrane in a neuron or other excitable cell (aka. nerve impulse)
110
axon
long, thin extension that conducts electrical signals away from a nerve cell body towards remote target cells
111
cell body
the spherical part of the neuron that contains the nucleus
112
dendrites
short, branching structure that extends from the surface of a nerve cell and receives signals from other cells
113
depolarisation
a shift in membrane potential, making it less negative on the inside of the cell
114
electrochemical driving force
the driving force for carrier-mediated passive transport of a charged solute x across the membrane.
115
inactivated state
116
myelin
an insulating layer, or sheath that forms around nerves, including those in the brain and spinal cord
117
nerve terminal
structure at the end of an axon that signals to another neuron or target cell
118
passive spread
119
refractory period
a period of time during which an organ or cell is incapable of repeating a particular action
120
threshold potential
the critical level to which a membrane potential must be depolarised to initiate an action potential
