2011 SEC Definition-style Questions
Higher Level Paper:
Term
Acceptable response per marking scheme
A situation in which one
organism lives on or in a
second species, feeding on
it and causing it harm.
parasitism
Organisms capable of
making their own food.
producers;
All the members of a
species living in an area.
population;
Micro-organisms and other
organisms that return
nutrients to the
environment by decay.
decomposers;
A situation in which two
organisms of different
species live together and
at least one benefits.
symbiosis;
A struggle between
organisms for a scarce
resource.
competition;
One organism killing and
eating another organism.
predation;
endotherm
(An animal that) produces its (own) body heat or (body) temperature
independent of (temperature of) environment
digestion
The breakdown of food
mechanical and chemical
digestion
Mechanical: physical or grinding or cutting or churning or chewing or
emulsifying
Chemical: enzyme or acidic action or molecular breakdown
Experiment
Test of hypothesis or test of prediction
Theory.
Hypothesis (or explained) supported (by experiment)
‘junk’ DNA
Non-coding DNA
protease
An enzyme that digests protein
contest competition and
scramble competition
Contest:
(Results in) winner takes all (of a limited resource)
Scramble:
(Results in) each gets some (of a limited resource)
qualitative and
Qualitative:
What is present
quantitative surveys
Quantitative:
How many present
adverse external
environment
positively phototropic
hormone
Surroundings that are harmful to organism(s)
Feedback
(in relation to hormone action)
When the level of a hormone (in the blood)
controls (the production) of another (or itself)
excretion
Eliminating waste Made in the body
evolution
Inheritable change within a population (or species) / in response to
change in the environment / by natural selection
a section of DNA that codes for one polypeptide (or protein or trait) or
unit of heredity
Gene
Growth towards light
A chemical messenger or product of endocrine (or ductless) gland
allele
(an alternative) form of a gene
Homozygous
identical alleles
heterozygous
different alleles (of a gene)
Genotype
genetic makeup or genes (alleles) present
phenotype
the expression of the genotype (and environment) or physical makeup
(or appearance)
genes on the same chromosome
Linkage
metabolism
(located) on sex-chromosome or on X- chromosome or on Ychromosome
(All) the chemical reactions in living cells
selectively permeable
Only some substances are allowed through
saprophytic
Feeding on dead matter
heterotrophic
Obtains food from other organisms or does not make its own food
sex linkage
2011 SEC Definition-style Questions
ORDINARY Level Paper:
Term
Acceptable response per marking scheme
Pollution
Any harmful addition to the ecosystem
Allele
alternative form of a gene
Heterozygous
two alleles
Phenotype
genotype expressed / genotype +environment
cancer
Control over cell division is lost
genetic screening
Checking / for presence of specific gene
Biosphere
Everywhere life is possible
Habitat
A place where organism(s) live
quantitative survey
A survey in which the number of a particular species/organism
is counted
Predator
Organism that kills & eats others
Conservation
Management of an ecosystem
photosynthesis
The method by which plants make their own food
Enzyme
A biological (or organic or protein) / catalyst
Immobilized
Attached to a (inert)substance/ trapped / in beads
( in relation to enzymes)
infertility
The inability to produce offspring / gametes
in vitro
In a glass vessel / Test tube
( in relation to fertilization)
excretion
Getting rid of waste / made in the body
Immunity
Defence against disease
vaccination
‘Safe dose’ of a pathogen / causing antibody production or
causing an immune response