Keywords Flashcards
(186 cards)
1
Q
Topic : Causes of disease
Pathogen
A
A micro-organism that causes disease
2
Q
Topic : Enzymes and Digestive system
Digestion
A
Physical and chemical breakdown of food
3
Q
Topic : Enzymes and Digestive system
Hydrolysis
A
Splitting up of molecules by adding water to them.
Enzymes do this to help break down molecules.
4
Q
Topic : Enzymes and Digestive system
Monomer
A
One of many small molecules that combine to form a
larger one
5
Q
Topic : Enzymes and Digestive system
Polymer
A
Larger molecule made up of repeating smaller
molecules
6
Q
Topic : Enzymes and Digestive system
Condensation Reaction
A
When 2 monosaccharides combine, water is removed
7
Q
Topic : Enzymes and Digestive system
Glycosidic Bond
A
The bond in a disaccharide
8
Q
Topic : Enzymes and Digestive system
Peptide Bond
A
The bond between 2 amino acids in a protein, formed
by a condensation reaction
9
Q
Topic : Enzymes and Digestive system
Polypeptide
A
A long chain of amino acids
10
Q
Topic : Enzymes and Digestive system
Hydrogen Bonds
A
Weak bonds between oxygen and hydrogen holding the
secondary structure of a protein in a coil
11
Q
Topic : Enzymes and Digestive system
Activation Energy
A
The minimum amount of energy needed to bring about
a reaction
12
Q
Topic : Enzymes and Digestive system
Active site
A
The region on an enzyme where the substrate fits
13
Q
Topic : Enzymes and Digestive system
Substrate
A
The molecule on which the enzyme acts
14
Q
Topic : Enzymes and Digestive system
Enzyme-Substrate Complex
A
Formed when an enzyme and a substrate fit together
and form temporary bonds
15
Q
Topic : Enzymes and Digestive system
Denaturation
A
Permanent changes in the structure of a protein;
enzyme’s active site changes shape so the substrate no
longer fits
16
Q
Topic : Enzymes and Digestive system
Competitive Inhibitor
A
Molecule that binds to the active site of an enzyme
17
Q
Topic : Enzymes and Digestive system
Non-competitive inhibitor
A
Bind to the enzyme at a position other than the active
site
18
Q
Topic : Cells and movement in and out of them
Resolution
A
The minimum distance apart 2 objects are, so that they
look like separate objects under the microscope
19
Q
Topic : Cells and movement in and out of them
Cell Fractionation
A
The process by which cells are broken up and the
organelles separated out
20
Q
Topic : Cells and movement in and out of them
Prokaryotic Cells
A
Cells that lack a nucleus and any membrane-bound
organelles
21
Q
Topic : Cells and movement in and out of them
Eukaryotic Cells
A
Cells that have a nucleus, chromosomes and other
membrane-bound organelles
22
Q
Topic : Cells and movement in and out of them
Saturated Lipids
A
Fatty acids with only C-C single bonds
23
Q
Topic : Cells and movement in and out of them
Unsaturated Lipids
A
Fatty acids with one or more C=C double bonds
24
Q
Topic : Cells and movement in and out of them
Hydrophilic
A
Attracted to water
25
Topic : Cells and movement in and out of them
Hydrophobic
Attracted to fat
26
Topic : Cells and movement in and out of them
Extrinsic Proteins
Proteins on the surface of the bilayer
27
Topic : Cells and movement in and out of them
Intrinsic Proteins
Proteins spanning the bilayer
28
Topic : Cells and movement in and out of them
Diffusion
The net movement of molecules or ions from a region
| of high concentration to a region of low concentration
29
Topic : Cells and movement in and out of them
Osmosis
The passage of water from a region of high water
potential to a region of low water potential, across a
partially permeable membrane
30
Topic : Cells and movement in and out of them
Active Transport
The movement of molecules or ions into or out of a cell
from a region of lower concentration to a region of
higher concentration using energy and carrier
molecules
31
Topic : Lungs and Lung Disease
Pulmonary
Ventilation
Tidal Volume x Ventilation Rate
32
Topic : Lungs and Lung Disease
Short Diffusion Pathway
Thin alveoli walls allow materials to cross quickly as the
| path is short
33
Topic : Lungs and Lung Disease
Diffusion Gradient
Movement of air and blood help to maintain diffusion
| gradients – keep Oxygen moving in and CO2 out
34
Topic : Lungs and Lung Disease
Pulmonary Fibrosis
Thickening of lung epithelia due to scarring
35
Topic : Lungs and Lung Disease
Asthma
An allergic reaction where histamine is released and the
| airway linings become inflamed
36
Topic : Lungs and Lung Disease
Emphysema
Destruction of the elastic tissue in the lungs due to
| smoking
37
Topic : The Heart and Heart Disease
Atrial Systole
Contraction of the atria
38
Topic : The Heart and Heart Disease
Ventricular Systole
Contraction of the ventricles
39
Topic : The Heart and Heart Disease
Diastole
Relaxation of the heart
40
Topic : The Heart and Heart Disease
Cardiac Output
The volume of blood pumped by one ventricle of the
| heart in one minute
41
Topic : The Heart and Heart Disease
Myogenic
Contraction of the heart is initiated from within the
| muscle itself
42
Topic : The Heart and Heart Disease
Sino-atrial node
SAN, sends out the initial wave of electrical activity to
| make the atria contract
43
Topic : The Heart and Heart Disease
Atrio-ventricular node
AVN, sends a wave of electrical activity down the
bundle of His, making the ventricles contract from the
base upwards
44
Topic : The Heart and Heart Disease
Atheroma
A fatty deposit in the wall of an artery
45
Topic : The Heart and Heart Disease
Aneurysm
Weakened artery walls swell and may burst
46
Topic : The Heart and Heart Disease
Thrombosis
When an atheroma breaks and a blood clot forms
47
Topic : The Heart and Heart Disease
Myocardial Infarction
A heart attack
48
Topic : The Heart and Heart Disease
Low-density lipoproteins
Transport cholesterol to tissues that may get deposited
49
Topic : The Heart and Heart Disease
High-density lipoproteins
Remove cholesterol from tissues
50
Topic : Immunity
Non-Specific Defences
Mechanisms that don’t distinguish between one type of
| pathogen or another e.g. skin
51
Topic : Immunity
Specific Defences
Mechanisms that do distinguish between different
| pathogens e.g. lymphocytes
52
Topic : Immunity
Phagocytosis
Pathogens are engulfed into vesicles (called
| phagosomes) and broken down by enzymes
53
Topic : Immunity
Antigens
Part of an organism that is recognised as non-self and
| triggers an immune response (usually they are proteins)
54
Topic : Immunity
Cell-mediated Immunity
T lymphocytes recognise antigen-presenting cells that
| have been invaded and undergo mitosis to respond
55
Topic : Immunity
Humoral Immunity
Immunity involving B cells and antibodies
56
Topic : Immunity
Antigenic Variability
Viruses such as flu have many different strains with
| different antigens on them
57
Topic : Immunity
Antibodies
Proteins synthesised by B cells, consisting of heavy and
| light chains and variable and constant regions
58
Topic : Immunity
Antigen-Antibody Complex
Formed when antigens bind to a specific site on the
| antibody
59
Topic : Immunity
Complementary Shape
Antigens have a shape that means they fit into their
| specific antibody
60
Topic : Immunity
Monoclonal Antibodies
Isolation and cloning of a single type of antibody
61
Topic : Immunity
Passive Immunity
The introduction of antibodies from an outside source
62
Topic : Immunity
Active Immunity
Stimulation of antibody production by the individual’s
| own immune system
63
Topic : Immunity
Vaccination
The introduction of a substance into the body with the
purpose of stimulating active immunity against a
particular disease
64
Topic : Immunity
Herd Immunity
Vaccinating most of a population so that no-one has the
| disease and transmission is stopped
65
Topic : Variation
Interspecific Variation
Differences between different species
66
Topic : Variation
Intraspecfic Variation
Differences between members of the same species
67
Topic : DNA and Meiosis
Nucleotide
Section of DNA made up of sugar, phosphate and a base
68
Topic : DNA and Meiosis
Complementary
A always bonds to T and C always bonds to G (they are
| complementary to each other)
69
Topic : DNA and Meiosis
Gene
A section of DNA that codes for making a polypeptide
70
Topic : DNA and Meiosis
Triplet Code
3 bases code for an amino acid
71
Topic : DNA and Meiosis
Chromosome
Thread-like structure made of protein and DNA, passes
| hereditary information on
72
Topic : DNA and Meiosis
Homologous Chromosomes
2 chromosomes determining the same characteristics
| one from mother, one from father
73
Topic : DNA and Meiosis
Allele
One of the different forms of a gene
74
Topic : DNA and Meiosis
Meiosis
Cell division that produces 4 haploid (half the
| chromosomes), genetically different, daughter cells
75
Topic : DNA and Meiosis
Locus
Position of a gene on a chromosome
76
Topic : DNA and Meiosis
Independent Segregation
Homologous pairs randomly separate during meiosis 1,
| into separate cells
77
Topic : DNA and Meiosis
Crossing Over
The process where chromatids break and rejoin with
| their homologous chromosome to exchange alleles
78
Topic : Genetic Diversity
Selective Breeding
Breeding individuals with desired characteristics
together and selecting the offspring that show the
desired characteristics
79
Topic : Genetic Diversity
Founder Effect
A few individuals colonise a new region, carrying a small
| amount of the alleles of the larger population
80
Topic : Genetic Diversity
Genetic Bottleneck
A drop in allele variety due to a large decrease in
| population size
81
Topic : The Variety of Life
Affinity for Oxygen
Haemoglobin (Hb) with a high affinity takes up oxygen
easily and releases in less readily. Hb with a low affinity
takes up oxygen less easily, but releases it more readily.
82
Topic : The Variety of Life
Associating
The process by which Hb combines with oxygen (in the
| lungs)
83
Topic : The Variety of Life
Dissociating
The process by which Hb releases oxygen (in the
| tissues)
84
Topic : The Variety of Life
Oxygen Dissociation Curve
The s-shaped curve shown by how Hb binds oxygen
| first molecule is hard to load, next 3 load easily
85
Topic : The Variety of Life
Starch
Storage molecule in plants, it is coiled, insoluble and can
| by hydrolysed to form α-glucose
86
Topic : The Variety of Life
Glycogen
Storage molecule in animals, which has short chains so
| it can be readily hydrolysed to α-glucose
87
Topic : The Variety of Life
Cellulose
Parallel chains of β-glucose joined by hydrogen bonds,
| forms microfibrils for strength
88
Topic : The Variety of Life
Chloroplasts
Organelle in plant cells containing grana, thylakoids and
| stroma. Photosynthesis occurs here.
89
Topic : The Cell Cycle
Semi-conservative Replication
The way DNA makes exact copies of itself by unwinding
the double helix. Each chain acts as a template for the
new strands.
90
Topic : The Cell Cycle
Mitosis
Cell division where 2 daughter cells are produced that
| have the same number of chromosomes as the parent
91
Topic : The Cell Cycle
Haploid
Cells have half the number of chromosomes
92
Topic : The Cell Cycle
Diploid
Cells have a full set of chromosomes
93
Topic : The Cell Cycle
Prophase
Chromosomes become visible, nuclear envelope
| disappears
94
Topic : The Cell Cycle
Metaphase
Chromosomes align along equator of cell
95
Topic : The Cell Cycle
Anaphase
Chromatids move to opposite poles
96
Topic : The Cell Cycle
Telophase
Nuclear envelope reforms
97
Topic : The Cell Cycle
Cell Cycle
A cell’s regular cycle of division, followed by periods of
| growth
98
Topic : Cellular Organisation
Cell Differentiation
Cells become specialised in their structure to suit their
| roles
99
Topic : Cellular Organisation
Tissue
A collection of similar cells that perform a specific
| function
100
Topic : Cellular Organisation
Organ
A combination of tissues, co-ordinated to perform a
| variety of functions
101
Topic : Cellular Organisation
Organ Systems
Organs working together as a single unit
102
Topic : Exchange and transport
Surface area to volume ratio
For exchange to be efficient, an organism needs a large
surface area to volume ratio (bigger animals have a
smaller ratio)
103
Topic : Exchange and transport
Spiracles
Pores on the body surface of insects that open and
| close to allow gases to diffuse in and out
104
Topic : Exchange and transport
Gill Lamellae
Parts of fish gills that increase the surface area and
| where the blood flows through for gas exchange
105
Topic : Exchange and transport
Countercurrent Exchange
Blood and water flow in opposite directions to maintain
| a diffusion gradient
106
Topic : Exchange and transport
Stomata
Pores in the underside of a leaf that can be opened and
| closed by guard cells
107
Topic : Exchange and transport
Double Circulatory System
Blood passes through the heart twice on a full circuit of
| the body
108
Topic : Exchange and transport
Arteries
Blood vessels that carry blood away from the heart
| small lumens, thick muscle and elastic layers
109
Topic : Exchange and transport
Veins
Blood vessels that carry blood back to the heart (large
| lumens, thin muscle and elastic layers, have valves)
110
Topic : Exchange and transport
Tissue Fluid
Fluid that surrounds the cells of the body, it supplies
| nutrients to the cells and removes waste products
111
Topic : Exchange and transport
Ultrafiltration
Filtration assisted by blood pressure
112
Topic : Exchange and transport
Apoplastic Pathway
Route through the cell walls by which water and
| minerals are transported into the plant
113
Topic : Exchange and transport
Symplastic Pathway
Route through the cytoplasm and plasmodesmata of
| plant cells by which water and minerals are transported
114
Topic : Exchange and transport
Cohesion
Water molecules stick together by hydrogen bonds
115
Topic : Exchange and transport
Cohesion-Tension
Transpiration pull on the water puts the xylem under
| pressure
116
Topic : Exchange and transport
Transpiration
Evaporation of water from a plant
117
Topic : Exchange and transport
Xerophytes
Plants adapted to living in dry conditions
118
Topic : Classification
Species
A group of similar organisms that can breed together to
| produce fertile offspring
119
Topic : Classification
Classification
Grouping of organisms
120
Topic : Classification
Taxonomy
Theory and practice of biological classification
121
Topic : Classification
Phylogeny
The evolutionary relationships between organisms
122
Topic : Evidence for Relationships Between Organisms
DNA Hybridisation
A technique used to determine the similarities between
| the DNA of different organisms
123
Topic : Evidence for Relationships Between Organisms
Hybridisation
Double strands form with one strand from each species,
closely related organisms will share complementary
bases
124
Topic : Evidence for Relationships Between Organisms
Courtship Behaviour
Signals and displays between males and females of the
| same species to enable successful mating to occur
125
Topic : Adaptation and Selection
Adaptation
Organisms adjust to suit the changing environment
| where they live
126
Topic : Adaptation and Selection
Mutations
A change in the base sequence of DNA
127
Topic : Adaptation and Selection
Conjugation
One bacterial cell transfers DNA to another bacterial
| cell
128
Topic : Adaptation and Selection
Antibiotics
Substances that can destroy or inhibit the growth of
| micro-organisms
129
Topic : Adaptation and Selection
Antibiotic Resistance
Antibiotics have a reduced effectiveness at killing
| bacteria due to chance mutations
130
Topic : Adaptation and Selection
Plasmids
Circular loops of DNA in bacteria
131
Topic : Biodiversity
Biodiversity
The variety in the living world (including number of
different species, variety of genes and the range of
habitats)
132
Topic : Populations
Ecosystem
Self-contained unit made up of the biotic and abiotic
| factors in an area
133
Topic : Populations
Population
A group of individuals of the same species in a habitat
134
Topic : Populations
Community
The organisms of all species that live in the same area
135
Topic : Populations
Abiotic Factors
Concerned with the non-living part of the environment
136
Topic : Populations
Biotic Factors
Concerned with the living organisms in the environment
137
Topic : Populations
Interspecific Competition
Competition between organisms of different species
138
Topic : Populations
Intraspecific Competition
Competition between organisms of the same species
139
Topic : ATP
Phosphorylation
The process of adding a phosphate group (e.g. ADP -->
| ATP)
140
Topic : Photosynthesis
Light Dependent Reaction
Stage of photosynthesis in which light energy is
| required to produce ATP and reduced NADP
141
Topic : Photosynthesis
Light Independent Reaction
Stage of photosynthesis which does not require light energy directly, but does need the products of the light
dependent reaction to reduce CO2 and form
carbohydrate
142
Topic : Photosynthesis
Oxidation
Loss of electrons, combining oxygen with a substance
143
Topic : Photosynthesis
Reduction
Gain of electrons, loss of oxygen from a substance
144
Topic : Photosynthesis
Electron Carrier Molecules
A chain of carrier molecules along which electrons pass,
| releasing energy in the form of ATP as they do so
145
Topic : Photosynthesis
Photolysis of Water
Light energy splits water molecules, yielding electrons,
| hydrogen ions and oxygen (light-dependent reaction)
146
Topic : Photosynthesis
Calvin Cycle
A biochemical pathway (part of the light-independent
reaction) where CO2 is reduced to form carbohydrate
CO2 + RuBP --> GP --> TP --> Glucose or RuBP
147
Topic : Respiration
Glycolysis
First part of cellular respiration in which glucose is
broken down (in the cytoplasm) to 2 molecules of
pyruvate
148
Topic : Respiration
Link Reaction
Process linking Glycolysis to the Krebs Cycle (in the
matrix of the mitochondria), where the 2 molecules of
pyruvate are converted to CO2 and acetylcoenzyme A
149
Topic : Respiration
Krebs Cycle
Introducing acetylcoenzyme A into a cycle of oxidationreduction
reactions (in the matrix of the mitochondria)
that yield some ATP and a large number of electrons
150
Topic : Respiration
Electron Transport Chain
Use of electrons from the Krebs Cycle to synthesise ATP
| via a series of oxidation-reduction reactions
151
Topic : Respiration
Anaerobic Respiration
Releasing energy from glucose without oxygen
(produces lactate in animals and ethanol in plants and
some micro-organisms)
152
Topic : Energy and Ecosystems
Trophic Level
Each stage in a food chain
153
Topic : Energy and Ecosystems
Consumers
An organism that obtains its energy by feeding on other
| organisms
154
Topic : Energy and Ecosystems
Gross Production
Total quantity of energy that the plants in a community
| convert to organic matter
155
Topic : Energy and Ecosystems
Net Production
Gross production – respiratory losses
156
Topic : Energy and Ecosystems
Energy Transfer
(Energy available after the transfer / energy available
| before the transfer) x 100
157
Topic : Energy and Ecosystems
Pyramid of Number
A pyramid drawn with bar lengths proportional to the
| numbers of organisms present
158
Topic : Energy and Ecosystems
Pyramid of Biomass
A pyramid drawn with bar lengths proportional to the
| mass of plants/animals
159
Topic : Energy and Ecosystems
Pyramid of Energy
A pyramid drawn with bar lengths proportional to the
| energy stored in organisms
160
Topic : Energy and Ecosystems
Selective Breeding
Breeding of organisms by human selection of parents
| for certain characteristics
161
Topic : Nutrient Cycles
Saprobiotic Micro-organism
(Saprophyte) An organisms that gets it food from the
| dead or decaying remains of other organisms
162
Topic : Nutrient Cycles
Greenhouse Gases
Gases such as methane and CO2 which trap more heat
| energy, raising the Earths temperature
163
Topic : Nutrient Cycles
Ammonification
Production of ammonia from e.g. urea and proteins
164
Topic : Nutrient Cycles
Nitrification
Converting ammonia into nitrites and then nitrates
165
Topic : Nutrient Cycles
Nitrogen Fixation
Conversion of nitrogen gas into nitrogen-containing
| compounds
166
Topic : Nutrient Cycles
Denitrification
Conversion of soil nitrates into mitrogen gas
167
Topic : Nutrient Cycles
Leaching
Process by which nutrients are washed from the soil
| into watercourses
168
Topic : Nutrient Cycles
Eutrophication
Consequence of an increase in nutrients in
| watercourses that leads to a decrease in biodiversity
169
Topic : Inheritance and Selection
Genotype
The genetic composition of an organism
170
Topic : Inheritance and Selection
Phenotype
The characteristics of an organism (often visible),
| resulting from its genotype and the environment
171
Topic : Inheritance and Selection
Gene
A length of DNA that codes for a polypeptide
172
Topic : Inheritance and Selection
Allele
One form of a gene
173
Topic : Inheritance and Selection
Homologous Chromosomes
A pair of chromosomes that have the same gene loci
| and determine the same features
174
Topic : Inheritance and Selection
Dominant
An allele that is always expressed in the phenotype
175
Topic : Inheritance and Selection
Recessive
An allele that is only expressed in the phenotype when
| there is another identical allele
176
Topic : Inheritance and Selection
Heterozygous
When the alleles are different for a particular gene
177
Topic : Inheritance and Selection
Homozygous
When the alleles are the same for a particular gene
178
Topic : Inheritance and Selection
Sex Linkage
Any gene that is carried on the X or Y chromosome
179
Topic : Inheritance and Selection
Co-dominance
Both alleles are equally dominant and are both
| expressed in a phenotype
180
Topic : Inheritance and Selection
Multiple Alleles
More than 2 possible alleles for a particular gene
181
Topic : Inheritance and Selection
Gene Pool
All the alleles of all the genes of all the individuals in a
| population at any one time
182
Topic : Inheritance and Selection
Allelic Frequency
The number of times the allele occurs within a gene
| pool
183
Topic : Inheritance and Selection
Stabilising Selection
Selection that favours average individuals
184
Topic : Inheritance and Selection
Directional Selection
Selection that favours individuals at one extreme
185
Topic : Inheritance and Selection
Speciation
The evolution of new species from existing species
186
Topic : Inheritance and Selection
Geographical Isolation
When a physical barrier prevents two populations from
| breeding with one another
