IGCSE BIOLOGY:VERIFIED QUESTIONS AND ANSWERS
Active transport
The process in which energy is used to move the particles of a substance against a concentration
gradient, that is, from a region where they are of lower concentration to a region where they are
of higher concentration.
Adaptation
Any characteristic of an organism that improves its chances of surviving in its environment.
Aerobic respiration
Respiration with oxygen. It's the oxidation of food substances in the presence of oxygen with the
release of a large amount of energy. Carbon dioxide and water are released as waste products.
Alleles
Different forms of a gene which occupy the same relative positions on a pair of homologous
chromosomes.
Anaerobic respiration
Respiration without oxygen. It's the oxidation of food substances in the absence of oxygen.
Anaerobic respiration releases less energy than aerobic respiration.
Arteries
Blood vessels which carry blood away from the heart.
Artificial selection
A method used by human beings to produce plants and animals with desired qualities.
Asexual reproduction
The process resulting in the production of genetically identical offspring from one parent,
without the fusion of gametes.
Assimilation
The process whereby some of the absorbed food materials are converted into new protoplasm or
used to provide energy.
Bioaccumulation
The process by which substances collect in all parts or part of a living organism.
Breathing
, The process that brings about an exchange of gases between an organism and its environment.
Capillaries
Microscopic thin-walled (one cell thick) blood vessels which carry blood from a small artery
(arteriole) to a small vein (venule).
Community
Populations of organisms living together and interacting with one another under the same
environmental conditions.
Conservation
The protection and preservation of natural resources of the environment.
Consumers
Organisms which obtain their energy by feeding on other organisms.
Continuous variation
Traits with phenotypes ranging from one extreme to the other. It is brought about by combined
(or additive) effects of many genes. It is affected by environmental conditions, e.g. intelligence,
height and skin colour in human beings.
Cross-pollination
The transfer of pollen grains from one plant to the stigma of a flower in another plant of the same
species.
Decomposers
Saprotrophs and detritivores. Organisms which obtain energy by breaking down dead organisms,
faeces and excretory products.
Desertification
The destruction of land leading to desert-like conditions.
Detoxification
The process of converting harmful substances into harmless ones in the body.
Differentiation
The process by which a cell becomes specialized for a specific function.
Diffusion
Active transport
The process in which energy is used to move the particles of a substance against a concentration
gradient, that is, from a region where they are of lower concentration to a region where they are
of higher concentration.
Adaptation
Any characteristic of an organism that improves its chances of surviving in its environment.
Aerobic respiration
Respiration with oxygen. It's the oxidation of food substances in the presence of oxygen with the
release of a large amount of energy. Carbon dioxide and water are released as waste products.
Alleles
Different forms of a gene which occupy the same relative positions on a pair of homologous
chromosomes.
Anaerobic respiration
Respiration without oxygen. It's the oxidation of food substances in the absence of oxygen.
Anaerobic respiration releases less energy than aerobic respiration.
Arteries
Blood vessels which carry blood away from the heart.
Artificial selection
A method used by human beings to produce plants and animals with desired qualities.
Asexual reproduction
The process resulting in the production of genetically identical offspring from one parent,
without the fusion of gametes.
Assimilation
The process whereby some of the absorbed food materials are converted into new protoplasm or
used to provide energy.
Bioaccumulation
The process by which substances collect in all parts or part of a living organism.
Breathing
, The process that brings about an exchange of gases between an organism and its environment.
Capillaries
Microscopic thin-walled (one cell thick) blood vessels which carry blood from a small artery
(arteriole) to a small vein (venule).
Community
Populations of organisms living together and interacting with one another under the same
environmental conditions.
Conservation
The protection and preservation of natural resources of the environment.
Consumers
Organisms which obtain their energy by feeding on other organisms.
Continuous variation
Traits with phenotypes ranging from one extreme to the other. It is brought about by combined
(or additive) effects of many genes. It is affected by environmental conditions, e.g. intelligence,
height and skin colour in human beings.
Cross-pollination
The transfer of pollen grains from one plant to the stigma of a flower in another plant of the same
species.
Decomposers
Saprotrophs and detritivores. Organisms which obtain energy by breaking down dead organisms,
faeces and excretory products.
Desertification
The destruction of land leading to desert-like conditions.
Detoxification
The process of converting harmful substances into harmless ones in the body.
Differentiation
The process by which a cell becomes specialized for a specific function.
Diffusion
