Scratch and bruise (image 5 of 7). Close-up of a scratch and bruise on a man's arm, five days after the injury occurred. The skin damaged by the scratch (at centre) has now healed leaving a slight scar. However, at the left of the scratch is a fresh scab (dark red) of clotted blood, due to reopening of the wound in that area. The bruise below the scratch has now fully developed. Break- age of the tiny blood vessels (capillaries) in the skin has caused much purple discoloration. Areas of yellow are due to the breakdown of haemoglobin (the blood's pigment). (See photo numbers M330/668-671 & M330/673-674 for the scratch & bruise on days 1-4 & through to day 7).