Theory question 101
Respiration(a)(i) Complete the table below with the respiratory surface of each of the listed organisms.
Organism | Respiratory surface
Tadpole (2 days old) |
Cockroach |
Domestic fowl |
Talinum |
Earthworm |
Amoeba |
(ii) State five characteristic features of respiratory surfaces in organisms. (b) Make a drawing, 4 cm – 6 cm long of the respiratory organ in Tilapia and label fully.
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(a)(i) Tadpole (2 days old): external gills.
Cockroach: tracheoles (tracheal system).
Domestic fowl: lungs (alveoli/air capillaries).
Talinum: stomata (and lenticels) – the moist surfaces of the mesophyll cells.
Earthworm: moist skin (body surface).
Amoeba: cell membrane (body surface).
(ii) Any five: large surface area; thin (one cell thick); moist; permeable to gases; well supplied with blood capillaries (where there is a blood system); well ventilated so a concentration gradient is kept.
(b) Drawing of a single gill, 4–6 cm, with title and labels: gill arch (bar), gill rakers, gill filaments (lamellae), (afferent and efferent blood vessels).
Name the actual surface across which gases pass, not just the organism's organ.