Y12 AS Unit 2. GCE BIOLOGY specification UNIT 1 BIOL1 BIOLOGY AND DISEASE 33.3% AS exam in Jan UNIT 2 BIOL2 THE VARIETY OF LIVING ORGANISMS 46.7 % AS.
CHAPTER 34 VERTEBRATE EVOLUTION AND DIVERSITY. 1.Notochord (disks) -longitudinal, flexible rod between digestive tube and nerve cord -large, fluid filled.
