Over very long time periods (thousands of years) the direction of Earth's axis slowly changes due to precession. The Earth rotates around once in 24 hours-that's a rate of 1000 miles per hour!. The time it takes for the Earth to rotate completely around once is what we call a day. It's Earth's rotation that gives us night and day. The combined effect of the Earth's tilt and its orbital motion result in the seasons.
The structures within the brain are made up of about 100 billion neurons, as well as trillions of support cells called glia. Neurons may be the more important cells in the brain that relay messages about what you're thinking, feeling, or doing. Bu...
Genes are made of the nucleic acid DNA. Hundreds of genes are linked together into enormous molecules called chromosomes (chromatin). Genes can be switched on or off and are indirectly responsible for making proteins which do the work of the cell. Structure. The nucleus is a large roundish organelle.