Theory question 102
Photosynthesis and Plant Nutrition(a) Name the gases involved in the photosynthesis of a plant. (b) State one role each of the gases named in 2(a). (c)(i) What is a variegated leaf? (ii) Which part of the variegated leaf would test positive when treated with iodine solution? (iii) State two reasons for the answer in 2(c)(ii). (v) Name one mineral element required by plants for the formation of the part that would test positive in 2(c)(ii). (d) The table below indicates different methods by which organisms obtain food. Place the following organisms under the headings in the table below: Human, Mushroom, Venus flytrap, Waterleaf plant, Tapeworm, Elephant grass, Housefly, Lichen, Spirogyra, Rhizopus.
Mode of Nutrition: Holozoic | Parasitic | Symbiotic | Saprophytic | Autotrophic
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(a) Carbon (IV) oxide (CO2) and oxygen (O2).
(b) CO2: raw material, its carbon is built into glucose. O2: by-product given off (released into the air for respiration).
(c)(i) A variegated leaf has green parts (with chlorophyll) and white or yellow parts (without chlorophyll).
(ii) The green parts.
(iii) The green parts contain chlorophyll, which traps light for photosynthesis; so only they make glucose, which is stored as starch; the white parts lack chlorophyll and make no starch.
(v) Magnesium (or nitrogen, or iron needed to make chlorophyll).
(d) Holozoic: Human, Housefly.
Parasitic: Tapeworm.
Symbiotic: Lichen.
Saprophytic: Mushroom, Rhizopus.
Autotrophic: Waterleaf plant, Elephant grass, Spirogyra, Venus flytrap (it photosynthesises; it also traps insects, so it may be accepted as holozoic too).
The part numbered (iv) is missing in the book; answer the parts as printed.