1 Characteristics and classification of living organisms

movement

an action by an organism or part of an organism causing a change of position or place

respiration

the chemical reactions in cells that break down nutrient molecules and release energy for metabolism

sensitivity

the ability to detect and respond to changes in the internal or external environment

growth

a permanent increase in size and dry mass

reproduction

the processes that make more of the same kind of organism

excretion

the removal of the waste products of metabolism and substances in excess of requirements

species

a group of organisms that can reproduce to produce fertile offspring

DNA as a means of classification

base sequences/order/pattern in DNA/genes; each species has unique DNA/genes; compare with reference DNA of known species; closely related species have fewer differences in base sequences

desc the features of Prokaryotes

circular DNA/chromosome; plasmid(s); cell membrane; cell wall (not made of cellulose); cytoplasm; capsule; small ribosomes

desc features of All arthropods

exoskeleton; jointed/segmented legs; at least 1 pair of legs; segmented body; bilateral body symmetry

State the features of viruses

genetic material; protein coat; parasitic/pathogenic; only reproduce in a host/do not show other features of living organisms; very small; not cellular/absence of organelles