The Cambrian Period marks an important point in the history of life on Earth; it is the time when most of the major groups of animals first appear in the fossil record. This event is sometimes called the "Cambrian Explosion," because of the relatively short time over which this diversity of forms appears
1. Sand particles are too big to dissolve so their density sinks them
2. Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles.
Answer:
The main function of the circulatory (or cardiovascular) system is to deliver oxygen to the body tissues, whilst simultaneously removing carbon dioxide produced by metabolism.
Prokayotivs are a type of cell
I think that about half of all babies are able to walk independently by 12 month of age. It said that babies tend to take their first steps from the age of 9. Babies usually start to crawl before they can walk. This is because their arm are usually more effective. After crawling they learn to stand up with their feet first and later learn to walk while holding things. The next step after that is walking.
Not all babies walk at the same time. There those that learn before the other so there is no need to worry if your child does not walk by 12 months.