Erythrocytes have a large surface area to allow the passage of oxygen. Also contains hemoglobin which binds to oxygen. Macrophages (white blood cells) are large to help engulf bacteria or viruses. They have long, thin pseudopods that help capture bacteria or viruses to be engulfed, destroyed and digested.http://media-2.web.britannica.com/eb-media/89/20889- 004-64D9A2F5.jpgMotor Neuron has adapted by being long, which helps them communicate with other parts of the body. The sheath acts as an insulator so messages arrive quickly. The dendrites connect to many other neurons.http://www.bbc.co.uk/schools/gcsebitesize/science/edexcel/responses_to_environment/thenervoussystemrev2.shtmlThe function of the male gamete (sperm) is to travel to the gamete female and connect inside to fertilize. the egg. The male gamete has a long tail to help it swim to reach the female gamete and a head to help get inside the female.