The correct options are:
- Matter is made of small particles.
- Matter's particles are in constant random motion or vibration
- There is empty space between matter's particles.
Anything which has mass and occupies shape is a matter. Matter is composed of particles. The particles of matter are very small in size and they attract each other. There is space between the particles. The particles are in continuous random motion, thus they have kinetic energy. on absorbing energy their movement increases.
The saliva has enzymes that start to break down food using the lock and key system.The teeth chews the food and begins mechanical break down of food
Answer:
Yes
Explanation: The more layers, the more water it absorbs.
Nitrogen fixation is the process by which nitrogen is taken from its relatively inert molecular form (N2) in the atmosphere and converted into nitrogen compounds useful for other chemical processes (such as, notably, ammonia, nitrate and nitrogen dioxide).
Nitrogen fixation is performed naturally by certain types of anaerobic bacteria. Legumes such as clover contain symbiotic bacteria of this type within nodules in their root systems, producing nitrogen compounds that help to fertilize the soil. See George Washington Carver.
Nitrogen can also be artificially fixed for use as fertilizer or in other industrial processes. The most popular method is by the Haber process. Artificial fertilizer production has achieved such scale that it is now the largest source of fixed nitrogen in the Earth's ecosystem.
(This is the definition from the http://encyclopedia.kids.net.au/page/ni/Nitrogen_fixation website)
