Inglise keel unit 5 answers
structure, stabilize soil max 4
[4]
21. (a) (i) sympatric; 1
(ii) ranges of two species, overlap/close together/AW;
no geographical barrier;
ref to behavioural/genetic/physiological/prezygotic barrier;
correct ref to named area of map; max 2
(b) ref to mate selection by size; ie large with large or small with small
ref to monogamy;
ref to intermediate sizes, at disadvantage/selected against/ora;
intermediate do not pass on alleles/ora;
suggested reason why intermediate at disadvantage/ora max 3