Download IB Biology syllabus – definitions.

IB Biology – Definitions required by the syllabus
IB Biology syllabus – definitions.
* Definition given in IB Biology syllabus
Summer homework directions: Study all the words for topics 1 through 6 (create a
Quizlet, notecards, Kahoot…?). Share this with me via email. The first week of
school we will have a vocabulary quiz.
TOPIC
WORD
DEFINITION
Topic 1: Cells
biology
Organelle
A discrete structure within a cell, with a specific function.*
Tissue
Degenerate
A group of cells similar to each other, along with their
associated intercellular substances, which perform the same
function within a multicellular organism.
A group of tissues which work together as a single unit to
perform a particular function within a multicellular organism.
A group of organs, vessels, glands, other tissues, and/or
pathways which work together to perform a body function
within a multicellular organism.
Thepassivemovementofmoleculesfromaregionofhigh
concentrationtoaregionoflowconcentration.
Thepassivemovementofwatermolecules,acrossapartially
permeablemembrane,fromaregionoflowersolute
concentrationtoaregionofhighersoluteconcentration.*
Compounds containing carbon that are found in living
organisms (except hydrogencarbonates, carbonates and oxides
of carbon).*
Proteins that act as biological catalysts, speeding the rate at
which biochemical reactions proceed but not altering the
direction or nature of the reactions.
A specific region of an enzyme where a substrate binds and
catalysis takes place.
A structural change in a protein that results in a loss (usually
permanent) of its biological properties. Refer only to heat and
pH as agents.*
Having more than one base triplet to code for one amino acid.*
Universal
Found in all living organisms.*
Cellrespiration
Controlled release of energy in the form of ATP from organic
compounds in cells.*
Chemiosmosis is a processes that synthesizes ATP by the
diffusion of hydrogen protons across a biological membrane via
the ATP synthase (a transport protein) due to a proton
gradient that forms on the other side of the membrane.
Organ
Organ system
Diffusion
Osmosis
Topic 2:
Molecular
biology
Organic
Enzyme
Active site
Denaturation
Chemiosmosis
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IB Biology – Definitions required by the syllabus
TOPIC
WORD
DEFINITION
Topic 3:
Genetics
Gene
A heritable factor that controls a specific characteristic. (The
differences between structural genes, regulator genes and
genes coding for tRNA and rRNA are not expected at SL).*
One specific form of a gene, differing from other alleles by
one or a few bases only and occupying the same gene locus as
other alleles of the gene.*
The whole of the genetic information of an organism.*
Allele
Genome
Gene mutation
Homologous
chromosomes
Genotype
A change in the base sequence of a gene on DNA. This could
be by substitution, deletion, or insertion of a base or bases.
The terms point mutation or frameshift mutation will not be
used.
A pair of chromosomes containing the same linear gene
sequences, each derived from one parent.
The alleles possessed by an organism.*
Phenotype
The characteristics of an organism.*
Dominant allele
Homozygous
An allele that has the same effect on the phenotype whether it
is present in the homozygous or heterozygous state.*
Dominant alleles mask the effects of recessive alleles.
An allele that only has an effect on the phenotype when
present in the homozygous state.*
Pairs of alleles that both affect the phenotype when present in
a heterozygote. (The terms incomplete and partial will no
longer be used.)*
The particular position on homologous chromosomes of a
gene.*
Having two identical alleles of a gene.*
Heterozygous
Having two different alleles of a gene.*
Carrier
An individual that has a recessive allele of a gene that does
not have an effect on their phenotype.*
Testing a suspected heterozygote by crossing it with a known
homozygous recessive. (The term backcross is no longer
used.)*
Genes found on sex chromosomes (X and Y chromosomes)
are said to be sex linked.
Testing an individual for the presence or absence of a gene.*
Recessive allele
Codominant alleles
Locus
Test cross
Sex linkage
Genetic screening
Clone
A group of genetically identical organisms or a group of cells
artificially derived from a single parent cell.*
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IB Biology – Definitions required by the syllabus
TOPIC
WORD
Topic 4 and 5:
Ecology
Ecology and Evolution
Ecosystem
Population
Community
Species
Habitat
Autotroph
(producer)
Heterotroph
(consumer)
Detritivore
Saprotroph
(decomposer)
Trophic level
Carrying
capacity
Random sample
Evolution
DEFINITION
The study of relationships between living organisms and
between organisms and their environment.*
A community and its abiotic environment.*
A group of organisms of the same species who live in the
same area at the same time.*
A group of populations living and interacting with each
other in an area.*
A group of organisms which can interbreed and produce
fertile offspring.*
The environment in which a species normally lives or the
location of a living organism.*
An organism that fixes chemical energy in the form of
organic molecules; it "makes its own food" and does not
require previously formed organic materials from the
environment; e.g. photoautotroph, chemoautotroph.
An organism that requires chemical energy from already
formed organic molecules.
Animal that consumes decomposing organic particles,
deriving nutrition primarily from microbes on the particles.
Organism that feeds by secreting digestive enzymes onto
its food source and absorbing the products of digestion.
Fungi and bacteria are examples.
Stage in a food chain or web leading from primary
producers (lowest trophic level) through primary
consumers (herbivores) to secondary and tertiary
consumers (carnivores).
Maximum average number or biomass of organisms that
can be sustained in a habitat over the long term. Usually
refers to a particular species, but can be applied to more
than one.
A method to ensure that every individual in a population
has an equal chance of being observed.
The process of cumulative change in the heritable
characteristics of a population.*
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IB Biology – Definitions required by the syllabus
TOPIC
WORD
DEFINITION
Topic 6: Human
Health and Physiology
Pathogen
An organism or virus that causes a disease.*
Excretion
The removal of metabolic waste products from the body.
Topic 7: Nucleic acids
Nucleosome
Transcription
Translation
Topic 8: Metabolism,
cell respiration, and
photosynthesis
Chemiosmosis
Topic 9: Plant Science
Transpiration
Pollination
Topic 10: Genetics
Recombination
Linkage group
Polygenic
inheritance
The loss of water vapour from the leaves and stems of
plants.*
The transfer of pollen from the male organ, where it is
formed, to the receptive region of a female organ, e.g. from
anther to stigma.
The reassortment of genes or characters into different
combinations from those of the parents. Recombination
occurs for linked genes by crossing over and, for unlinked
genes, by chromosome assortment* due to random
alignment during metaphase I and II of meiosis.
Genes that are located on the same chromosome are part of
a linkage group; the closer together the genes are, the lower
the probability that they will be separated by crossing-over
during meiosis in, and hence the greater the probability that
they will be inherited together.
A trait or characteristic that is influenced by the expression
of more than one gene, e.g. hair colour in humans.
Continuous variation occurs as a result.
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IB Biology – Definitions required by the syllabus
TOPIC
WORD
DEFINITION
Topic 11: Animal
physiology
Active immunity
Natural immunity
Immunity due to the production of antibodies by the
organism itself after the body’s defence mechanisms have
been stimulated by invasion of foreign micro-organisms.*
Immunity due to the acquisition of antibodies from another
organism in which active immunity has been stimulated,
including via the placenta or in colostrum.*
Immunity due to infection.*
Artificial immunity
Immunity due to inoculation with vaccine.*
Resting potential
The difference in electrical charge across the plasma
membrane of a neuron when not conducting nerve impulses
(i.e. resting). In humans, the value is around -70mV,
meaning the inside is negative relative to the outside of the
cell.
Voltage change generated across the membrane of a nerve or
muscle cell when the cell is activated by electrical, chemical
or mechanical stimuli. In humans, the value is around
+40mV. The action potential is propagated along the nerve
by voltage-gated ion channels.
The control of the water balance of the blood, tissue or
cytoplasm of a living organism.*
The amount of energy fixed by autotrophs, in kJ m-2 yr-1.
Passive immunity
Action potential
Osmoregulation
Option G: Ecology
and Conservation
Gross production
Net production
Biomass
Biomagnification
Option H: Further
Human Physiology
Partial pressure
Gross production less the energy used by the autotrophs for
their own respiration, in kJ m-2 yr-1.
A quantitative estimate of the entire amount of living
organisms in a particular habitat; it can be measured in terms
of volume, mass, or caloric energy.
process in which chemical substances become more
concentrated at each trophic level.
The pressure exerted by an individual gas in a mixture of
gases; measured in kPa (or mm Hg).
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