Some grape growers spray plant hormones onto grape flowers that have not been pollinated. The flowers develop into seedless grapes. Which statement explains why the grapes have no seeds?
The fruit develops without fertilisation, so no seeds are formed.
The hormones kill the seeds after fertilisation has taken place.
The hormones make the seeds germinate inside the growing fruit.
The hormones speed up ripening, so seeds have no time to form.
84 exam-style questions on OCR GCSE Biology 3.2 Coordination and control – the endocrine system, covering 3.2.1 Principles of hormonal coordination and control, 3.2.2 Roles of thyroxine and adrenaline, 3.2.3 Hormones in human reproduction, 3.2.4 Interactions of reproductive hormones, 3.2.5 Hormones in contraception, 3.2.6 Hormones in reproductive technologies, 3.2.7 Plant hormones in growth and coordination, 3.2.8 Effects of plant hormones, and 3.2.9 Uses of plant hormones. Each one has a worked solution and a mark scheme showing where the marks go.