has many mitochondria Explanation: to transfer a lot of energy or a lot of energy is needed to swim produces enzymes/chemicals Explanation: to help it digest / enter the egg nucleus only contains 23 chromosomes Explanation: to produce a full set of chromosomes at fertilisation 02.2 55 µm Allow 2 marks 3 AO2 for 0.055 (mm). B1.1.5 Allow 1 mark for WS 1.2, 3.3, 4.2, correct 4.3, 4.4, 4.5 substitution or MS 1a, 2h, 3a, 3b reorganisation. 03.1 Air bubbles 1 AO3 B1.1.2 Lower the coverslip using a mounted 1 WS 2.2, 2.3, 2.4, needle. 2.7, 3.5 03.2 Too much used. 1 AO3 B1.1.2 Use a filter paper/tissue to soak up 1 WS 2.2, 2.3, 2.4, the excess. 2.7, 3.5 03.3 Bigger field of view 1 AO3 B1.1.5 (so) it is easier to focus 1 WS 2.2, 2.3, 2.4, 2.7 04.1 Carbon dioxide: Z 1 AO3 B1.3.1 Oxygen: Y 1 WS 1.2, 3.5 04.2 diffusion 1 AO1 WS 4.1 AO / Question Answers Extra information Mark Spec. Ref. 04.3 Level 3: A clear and detailed description of osmosis and 5–6 active transport including references to the relative concentrations of the substances.
has many mitochondria Explanation: to transfer a lot of energy or a lot of energy is needed to swim produces enzymes/chemicals Explanation: to help it digest / enter the egg nucleus only contains 23 chromosomes Explanation: to produce a full set of chromosomes at fertilisation 02.2 55 µm Allow 2 marks for 0.055 (mm). Allow 1 mark for correct substitution or reorganisation. 3 AO2 B1.1.5 WS 1.2, 3.3, 4.2, 4.3, 4.4, 4.5 MS 1a, 2h, 3a, 3b 03.1 Air bubbles Lower the coverslip using a mounted needle. 1 1 AO3 B1.1.2 WS 2.2, 2.3, 2.4, 2.7, 3.5 03.2 Too much used. Use a filter paper/tissue to soak up the excess. 1 1 AO3 B1.1.2 WS 2.2, 2.3, 2.4, 2.7, 3.5 03.3 Bigger field of view (so) it is easier to focus 1 1 AO3 B1.1.5 WS 2.2, 2.3, 2.4, 2.7 04.1 Carbon dioxide: Z Oxygen: Y 1 1 AO3 B1.3.1 WS 1.2, 3.5 04.2 diffusion 1 AO1 WS 4.1 Question Answers Extra information Mark AO / Spec. Ref. 04.3 Level 3: A clear and detailed description of osmosis and active transport including references to the relative concentrations of the substances. 5–6