Biology key words

Across

• 1. The movement of particles from an area of high concentration to an area of low concentration. (9)
• 4. When the two alleles for a particular gene on a pair of chromosomes are different. (12)
• 6. The part of the brain which regulates body functions and controls production of many hormones. (12)
• 7. Removal of undigested food from the body in faeces. (8)
• 8. The breakdown of an enzyme when too hot or in different pH. (9)