Discusses symptoms of the various types of headaches, including migraine, cluster, and muscle contraction (tension) headaches, and explores what is known of their causes and cures.
Describes the structure and characteristics of the Amoeba, Paramecium and other members of the "circus" that Leeuwenhoek discovered in a drop of water.
Describes the structure and characteristics of the Amoeba, Paramecium and other members of the "circus" that Leeuwenhoek discovered in a drop of water.
Discusses the evolution of dogs and their uses throughout history and includes information on different breeds, training, care as pets, relationship with people, and other relevant topics.
Examines the changes in the atmosphere that produce various weather phenomena, and looks at how weather patterns over a period of time determine the climates of the Earth's various regions.
A detailed presentation of the structure and function of different types of cells and of research into developing technologies such as cloning and the use of stem cells.
Discusses plate tectonics, the theory that the surface of the earth is always moving, and the connection of this phenomenon to earthquakes and volcanoes.
Discusses the concepts of time and biological cycles, including the phases of the moon, the internal clocks of plants and animals, seasonal rhythms, and the aging process.
