Theory question 101
Characteristics and Classification of Living Things(a)(i) List three characteristics of living organisms. (ii) Explain briefly the characteristics listed in 1(a)(i) above.
(b) In a tabular form, state four differences between plants and animals.
(c)(i) Name one organism that exhibits both plant and animal features. (ii) State four animal features and two plant features possessed by the organism named in 1(c)(i) above.
Show the model answer
(a)(i) Any three: nutrition; respiration; excretion; growth; reproduction; irritability (sensitivity); movement.
(ii) Each explained, e.g. Nutrition — obtaining or making food for energy and growth; Respiration — breaking down food to release energy; Excretion — removing waste products of metabolism; Growth — permanent increase in size/dry mass; Reproduction — producing new individuals of the same kind; Irritability — responding to changes (stimuli) in the environment; Movement — changing position of the body or its parts.
(b) Table (any four) — Plants: autotrophic (make food by photosynthesis) / Animals: heterotrophic; have chlorophyll / no chlorophyll; cellulose cell wall / no cell wall; usually fixed, move only parts / move whole body; growth at tips, indefinite / growth all over, definite; store starch / store glycogen; no special sense or excretory organs / have them; respond slowly / respond quickly.
(c)(i) Euglena (or Chlamydomonas).
(ii) Animal features (Euglena): moves with a flagellum; has a gullet; has a pellicle and no cellulose wall; has a contractile vacuole; has an eyespot; can feed heterotrophically in the dark. Plant features: has chloroplasts/chlorophyll; makes food by photosynthesis; stores paramylon (starch-like).
In (b) set each plant feature against the matching animal feature.