Biology key terms

The late stage of HIV infection, when the immune system is so badly damaged that it cannot deal effectively with other infections or cancers.

The spread of a pathogen through the air, for example in droplets breathed out by a person or in wind-blown fungal spores.

A rapid increase in the growth of algae in water.

A form of a gene.

The proportion of all copies of a gene in a population that consist of a particular allele.

A version of a gene. Different alleles are genetic variants of that gene.

A tiny air sac in the lungs where oxygen enters the blood and carbon dioxide leaves it.

A building-block molecule that can join with others to form a protein.

A toxic nitrogen-containing substance formed when excess amino acids are deaminated in the liver.

A carbohydrase that breaks down starch into maltose.

Describes a process that occurs without oxygen.

Decay that occurs without oxygen and can produce methane.

Decomposition in conditions where oxygen is absent or scarce.

Respiration that transfers energy from glucose without using oxygen.

A procedure that widens a narrowed artery, usually using a balloon and often a stent.

A result that is noticeably different from the other repeated results.

A result that does not fit the overall pattern shown by the other data.

Having opposite effects; insulin and glucagon are antagonistic because one lowers blood glucose concentration while the other raises it.

Two effectors whose actions oppose one another, allowing a controlled variable to be changed in either direction.

Responses that have opposing effects, such as mechanisms that increase heat loss and mechanisms that reduce it.

A substance that kills bacteria or stops them growing.

A medicine that kills bacteria or stops them growing.

A small paper disc containing an antibiotic, placed on an inoculated agar plate to test its effect on bacterial growth.

An inherited characteristic that allows a bacterium to survive exposure to an antibiotic that would normally kill it or stop its growth.

A gene used to identify cells that have taken up DNA; an antibiotic resistance marker allows those cells to survive exposure to a particular antibiotic.

A protein made by white blood cells that binds specifically to an antigen.

A triplet of bases on tRNA that pairs with a complementary codon on mRNA.